Menstrual health and factors associated with school absence among secondary school girls in Luang Prabang Province, Lao People's Democratic Republic: A cross-sectional study.

In Lao People's Democratic Republic (Lao PDR), information on school sanitation and menstrual health among secondary school girls is limited. This study aimed to explore knowledge and practices surrounding menstrual health and to identify factors associated with school absence due to menstruation among secondary school girls in Lao PDR. The study involved 1,366 girls from grade 9 to grade 12 in six secondary schools in Luang Prabang Province. Data on socio-demographics and menstrual health of the girls and data on school toilets was collected. Logistic regression analysis was performed to identify the factors associated with school absence due to menstruation. The mean age was 15.8 years old. The average age of menarche was 12.9 years old. Of 1,366 girls, 64.6% were shocked or ashamed when they reached menarche and 31.8% had been absent from school due to menstruation in the six months before this study was conducted. Factors associated with school absence due to menstruation were age ≥ 16 years old (AOR = 1.79, 95% CI 1.37-2.34), higher income (AOR = 2.38, 95% CI 1.16-4.87), menstrual anxiety (AOR = 1.55, 95% CI 1.09-2.20), using painkillers (AOR = 4.79, 95% CI 2.96-7.76) and other methods (AOR = 2.82, 95% CI 1.86-4.28) for dysmenorrhea, and disposing used pads in places other than the school's waste bins (AOR = 1.34, 95% CI 1.03-1.75). Living with relatives (AOR = 0.64, 95% CI 0.43-0.95) and schools outside the city (AOR = 0.59, 95% CI 0.38-0.90) were significantly less associated with school absence. Although the association between school toilets and school absence was not examined, the results of this study suggest that school toilets should be gender-separated and equipped with waste bins in the toilet. Furthermore, menstrual education should start at elementary schools and teacher training on menstrual health should be promoted.

Introduction

Menstruation is a natural process of the female reproductive system. Girls express their secondary sex characteristics, both physiology and emotions, and change through the adolescent period [1]. Adolescence is a transition period where girls experience cognitive development and social changes take place [2]. It is a crucial part of human life because whether a girl develops into a healthy adult predominantly depends on how she is nurtured during the adolescence period [3].

At menarche, girls often experience negative feelings, including fear, shame, and guilt towards their families [4], because they lack menstrual information and they are not prepared for reaching menarche [5]. Menstrual hygiene practices vary among girls according to different levels of knowledge [6], area of residence [7], disposable (commercial) pad availability [4, 8, 9], and available sanitation facilities [10, 11]. Poor menstrual hygiene management is associated with poor mental health and poor physical health, such as urinary tract infection and bacterial vaginosis [12-15]. Bacterial vaginosis may cause reproductive tract infections and lead to pelvic inflammatory disease [14, 16], and unhygienic practices during menstruation is reported to be one of risk factors of secondary infertility [16, 17]. In addition, poor menstrual health can influence school attendance as well as academic performance [4, 18–20]. In the worst case, girls drop out of school because they cannot manage their menstrual hygiene when they are at school [19, 20].

Female inclusion in education has been prioritized globally because improving girls’ education can delay child rearing, increase contraceptive uptake, and improve the nutritional status and vaccination rate of their children when they become mothers [21, 22]. Furthermore, girls who obtain accurate and pragmatic information on sexual and reproductive health are less likely to encounter sexually transmitted diseases, unintended pregnancy, and abuse [23]. However, school environments, including sanitation facilities, are often not supportive due to a lack of adequate water and inadequate toilet facilities [24-26]. Therefore, increasing attention has been paid to improving menstrual hygiene management and integrating menstruation into the Water, Sanitation and Hygiene (WASH) programs to ensure that girls can maintain their school attendance and manage their menstruation with comfort and hygiene while in school [12, 27].

In Lao People’s Democratic Republic (Lao PDR), approximately 59% of schools did not have sanitation facilities and 61% of schools did not have improved water source in 2008 [28]. Therefore, many students had to return home to use the toilet or defecate in the forest. WASH programs were first implemented in Lao PDR in 1990. They aim to establish safe water, provide hygiene education, and ensure that Lao people can access adequate sanitation. Through a number of governmental and non-governmental organizations led WASH initiatives, Lao PDR has made significant progress in increasing the use of improved sanitation facilities throughout the country as 73.8% of households had access to improved toilets (either shared or privately owned toilets) in 2017 [29]. The Lao Social Indicator Survey in 2017 reported that 81% of Lao women and girls had private places to wash and change menstrual pads when they were at home [29]. However, this does not mean that Lao girls can properly manage their menstruation and access adequate sanitation facilities at school. In addition, it was reported that maintaining good menstrual hygiene was difficult for girls in rural areas in Savannakhet Province and in the northern part of Lao PDR [30]. Therefore, this study aimed to explore knowledge and practices surrounding menstrual health and to identify factors associated with school absence due to menstruation among secondary school girls in Luang Prabang Province, which is located in the northern part of Lao PDR.

Materials and methods

Study design and setting

This was a cross-sectional study conducted at six secondary schools in Luang Prabang Province from November 19 to November 27, 2020. Luang Prabang Province consists of 12 districts with a population of 431,889 from diverse ethnic groups [31]. According to a report by the Ministry of Education and Sports, there are 45 public and two private secondary schools (grades 6–12), and 20,851 students (9,606 girls) of grades 9–12 in the province [32]. Six schools were selected from the 45 public secondary schools. Four schools (Santiphab secondary school, Phanluang secondary school, Pongkham secondary school, and Pasathipatai secondary school) were selected from 24 schools in Luang Prabang City (Luang Prabang District) by simple random sampling using a lottery method. Two schools were selected from 21 schools in 11 districts, outside the city, by convenience sampling considering their accessibility; Chomphet secondary school in Chomphet District, and Sobjaek secondary school in Pakxeng District.

Study population

The study population were secondary school girls of grades 9–12 at the six schools who had reached menarche. Girls who had not reached menarche and who did not provide written informed consent nor parental consent were excluded from the study. Among the 1,515 girls of grades 9–12 in the six schools, 32 girls who had not reached menarche and 117 girls who did not answer all questions were excluded. A total of 1,366 girls were included in the study with a 91.4% questionnaire completion rate among all menstruating girls.

Data collection instrument and procedure

Data was collected using a structured and self-administered questionnaire. The questionnaire for girls consisted of four sections: socio-demographic information, reproductive information, menstrual knowledge, and menstrual hygiene practice. The questionnaire was developed by retrieving questions from different literatures and was adapted to the Lao cultural context [4, 8, 9, 33, 34]. A pretest was conducted including 30 young females via an online platform to ensure age-level comprehension and a coherent order of questions.

A checklist to assess school toilets was developed based on the results of menstrual hygiene practices in this study, by referring to a previous study [11] and the United Nations Children’s Fund (UNICEF) Guidance on Menstrual Health and Hygiene [35]. The information addressed in the checklist included general information about the schools and characteristics of the school toilets. General information composed of the total number of students and girl students, the total number of toilets for students and for girl students, type of toilets, and the cleanliness level of the toilets. The characteristics of the school toilets comprised of gender-separated, distance between male toilets and female toilets, water availability, toilet paper availability, a door latch on each toilet cubicle, light bulbs, waste bins availability, and basin for handwashing. The toilet data was collected using the checklist by an officer of the Luang Prabang Provincial Department of Education and Sports from March 29 to April 2, 2021. The officer was trained in data collection and had previously participated in data collection from girls from November 19 to November 27, 2020.

Variables

Socio-demographic factors were categorized as follows: the age of the participants was categorized as < 16 years old and ≥ 16 years old based on the mean age (15.8 years old). According to the National Ethnolinguistic Classification, there are four ethnolinguistic groups in Lao PDR: Lao-Tai, Hmong-Mien, Mon-Khmer and Chinese-Tibetian [29]. However, three ethnolinguistic groups were presented in this study: Lao-Tai, Hmong-Mien, and Mon-Khmer. Three religions were identified in this study: Buddhist, Animism, and Christian. Allowance per week referred to the amount of money that girls received from parents or obtained in a week and was categorized into five groups: 15,000 Lao Kip (LAK), 20,000–40,000 LAK, 50,000–100,000 LAK, 110,000–200,000 LAK, and more than 200,000 LAK (1 USD = 9,453 LAK, as of June 4, 2021). Parental education was classified into five levels: no education, primary school, lower secondary school, upper secondary school, and diploma level or higher. Residential information was obtained to identify where and with whom girls lived and responses were divided into three groups: living with parents, staying with relatives, and staying at a dorm/rental apartment.

Reproductive information was collected to understand the girls’ experiences related to menstruation. Age of menarche was classified into three groups based on the mean age of menarche (12.9 years old): < 13 years old, 13 years old, and > 13 years old. Sources of information regarding menstruation prior to the onset of menarche were divided into: none (no information obtained), mothers, sisters, teachers, friends, and others. The shock and feeling of shame that girls had at the onset of menarche referred to their mental preparation for menarche, and was categorized into two groups (yes and no). Menstrual absorbents were divided into four choices: disposable pads, reusable pads, cloth from old towel/skirts, and combined usage of disposable and reusable pads. Disposable pads in this study referred to any commercial and single use pads that are disposed after one use. Dysmenorrheal management was classified into five groups based on the answers by girls who had dysmenorrhea: lay on stomach, take painkillers, drink hot water, others, and nothing (because it is not so painful). Information on school absence was obtained by asking if a student had been absent from the classroom/school due to menstrual anxiety, menstrual leak, and/or dysmenorrhea in the last six months. The answers were categorized into yes, no, and no response. Girls who did not answer about school absence due to menstruation were not included.

Questions to identify the level of menstrual knowledge and menstrual hygiene practices were retrieved from literature reviews [4, 8, 9, 33, 34]. Five questions concerning menstruation were used to evaluate girl’s knowledge [33]: ‘What is menstruation?’, ‘What causes menstruation?’, ‘Which organ is the origin of menstruation?’, ‘What is the normal menstruation cycle?’, and ‘In which phase of the menstrual cycle are women most likely to get pregnant if they have sexual intercourse?’ Regarding the latter question, answer choices included: menstrual phase (day 1–7 of menstrual cycle), follicular/proliferation phase (day 8–12 of menstrual cycle), ovulation phase (day 14 of menstrual cycle), and luteal phase (day 15–28 of menstrual cycle). Girls who answered 3–5 questions correctly and 1–2 questions were categorized into ‘good knowledge’ and ‘some knowledge’, respectively. Girls who did not get any correct answers and those who answered ‘don’t know’ were categorized into ‘poor knowledge’.

Data analysis

The study used Statistical Package for Social Sciences, version 26 (IBM SPSS Inc, Armonk, NY, USA) for data analysis. Descriptive statistics were used to describe the characteristics of participants and their situation. Logistic regression analysis was performed to obtain the odds ratio (OR) and 95% confidence interval (CI). P value < 0.05 was considered as statistically significant.

Ethical considerations

The study was approved by the National Ethics Committee for Health Research in Lao PDR (No. 066/NECHR). Written informed consent was obtained from all girl who enrolled in the study. For all participants aged under 18 years old, written informed consent was also obtained from their guardians including parents, relatives, and teachers before the data collection. The data collection team visited the schools and distributed the forms for guardians three days before the data collection.

Results

Socio-demographics of the girls

Among the 1,366 participants from the six schools in Luang Prabang Province, the age of girls ranged from 13 to 19 years old and the mean age was 15.8 years old. Most girls were Lao-Tai (66.6%) and Buddhist (68.5%) (Table 1). The majority lived with their parents (77.9%) and the average allowance per week was 20,000–40,000 LAK (39.7%). Regarding the parental education level, most fathers were educated at university (34.0%). On the other hand, more than half of the mothers were educated at lower secondary school or lower (Table 1).

Table 1

Socio-demographic characteristics of secondary school girls in Luang Prabang Province (N = 1,366).

Variables	Categories	n (%)
Age
	< 16 years old	567 (41.5)
	≥ 16 years old	799 (58.5)
Ethno-linguistics
	Lao-Tai	910 (66.6)
	Hmong-Mien	247 (18.1)
	Mon-Khmer	209 (15.3)
Religion
	Buddhist	936 (68.5)
	Animism	389 (28.5)
	Christian	41 (3.0)
Residence
	Live with parents	1064 (77.9)
	Live with relatives	179 (13.1)
	Stay at dormitory/rental apartment	123 (9.0)
Area of school
	Inside Luang Prabang City	1137 (83.2)
	Outside Luang Prabang City	229 (16.8)
Allowance per week
	< 15,000 LAK	198 (14.5)
	20,000–40,000 LAK	427 (31.3)
	50,000–100,000 LAK	542 (39.7)
	110,000–200,000 LAK	147 (10.8)
	> 200,000 LAK	52 (3.8)
Father’s education
	No education	61 (4.5)
	Primary school	297 (21.7)
	Lower secondary school	233 (17.1)
	Upper secondary school	311 (22.8)
	Diploma or higher	464 (34.0)
Mother’s education
	No education	166 (12.2)
	Primary school	365 (26.7)
	Lower secondary school	269 (19.7)
	Upper secondary school	312 (22.8)
	Diploma or higher	254 (18.6)

Reproductive characteristics of the girls

The average age of menarche among the girls was 12.9 years old. Of 1,366 girls, 64.6% were shocked or ashamed when they reached menarche (Table 2). Most girls responded that they had dysmenorrhea (88.9%). Regarding dysmenorrhea management, the majority of girls (41.9%) reported that they managed dysmenorrhea by drinking hot water. Some of them managed it by laying on their stomach (18.6%) and taking painkillers (16.2%). The major source of menstrual information was mothers (46.9%) and 28.2% of the girls did not have any information about menstruation before menarche.

Table 2

Reproductive characteristics of secondary school girls in Luang Prabang Province (N = 1,366).

Variables	Categories	n (%)
Age of menarche
	< 13 years old	467 (34.2)
	13 years old	477 (34.9)
	> 13 years old	422 (30.9)
Feeling shock and/or ashamed at the menarche
	Yes	883 (64.6)
	No	483 (35.4)
Duration of menstruation
	1–2 days	8 (0.6)
	3–7 days	1330 (97.4)
	≥ 8 days	28 (2.0)
Regularity of menstruation
	Yes	984 (72.0)
	No	382 (28.0)
Dysmenorrhea
	Yes	1215 (88.9)
	No	151 (11.1)
Dysmenorrhea management
	Lay on stomach	254 (18.6)
	Painkillers	221 (16.2)
	Drink hot water	573 (41.9)
	Othersa	76 (5.6)
	Nothing, because it is not so painful	91 (6.7)
Source of menstrual information before menarche attainment
	None	385 (28.2)
	Mother	640 (46.9)
	Sister	188 (13.8)
	Teacher	67 (4.9)
	Friend	62 (4.5)
	Othersb	24 (1.8)

aOthers include traditional medicine, hot pack on stomach, and/or one or more methods combined.

bOthers include reading books and searching the Internet.

Menstrual knowledge of the girls

Misconceptions about menstruation existed among the girls in Luang Prabang Province. Most girls (68.4%) believed that menstruation was bad blood that a woman’s body shed monthly. While 546 girls (40.0%) answered that it was because a woman’s body wanted to shed bad blood out of her system, 11 girls (0.8%) believed that it was caused by disease (Table 3). Of the 1,366 participants, 208 girls (15.2%) knew that women could get pregnant when they had sexual intercourse during the ovulation phase of the menstrual cycle. The majority of girls had ‘some knowledge’ about menstruation (61.6%) and only 13.9% of girls had ‘good knowledge’.

Table 3

Knowledge of menstruation among secondary school girls, Luang Prabang Province (N = 1,366).

Variables	Categories	n (%)
What is menstruation?
	Bad blood that women shed monthly	934 (68.4)
	Normal bleeding from a woman’s body	297 (21.7)
	Disease	27 (2.0)
	Other answers	8 (0.6)
	Don’t know	100 (7.3)
Cause of menstruation
	Hormones	628 (46.0)
	Body wants to shed bad blood	546 (40.0)
	Disease	11 (0.8)
	Other answers	11 (0.8)
	Don’t know	170 (12.4)
Origin of menstrual blood
	Blood vessel	14 (1.0)
	Uterus	418 (30.6)
	Abdomen	1 (0.1)
	Bladder	8 (0.6)
	Birth canal	623 (45.6)
	Don’t know	302 (22.1)
Normal menstrual interval
	20–30 days	442 (32.4)
	28–30 days	291 (21.3)
	30–40 days	57 (4.2)
	Don’t know	576 (42.2)
In which phase of the menstrual cycle are women most likely to get pregnant if they have sexual intercourse?
	Menstrual phase	131 (9.6)
	Follicular/proliferation phase	116 (8.5)
	Ovulation phase	208 (15.2)
	Luteal phase	28 (2.0)
	Don’t know	883 (64.6)
Menstrual knowledge
	Good knowledge*	190 (13.9)
	Some knowledge**	841 (61.6)
	Poor knowledge***	335 (24.5)

*Girls correctly answered 3–5 questions of 5 questions.

**Girls correctly answered 1–2 questions of 5 questions.

***Girls answered all 5 questions incorrectly.

Menstrual hygiene practices amongst the girls

Most girls reported using disposable pads (96.6%), changing their pads 2–3 times in one menstrual day (67.1%), and having easy access and being able to afford disposable pads (80.9%) (Table 4). Among the girls, 60.1% were satisfied with the frequency they changed their pads. Regarding using the school toilets, 64.6% of girls reported that they tried to avoid using the school toilets and 77.7% reported that they tried to avoid changing their pads at school. When they did change their pads at school, the majority of girls (73.2%) disposed of their used pad in the school waste bins (either inside the school’s toilets or waste bins near the school), however, 23.8% of girls kept the used pads in a plastic bag and took them home for disposal (Table 4). There were 434 girls (31.8%) who reported that they had been absent from school due to menstruation during the past six months (Table 4).

Table 4

Menstrual hygiene practices among girls in Luang Prabang Province (N = 1,366).

Variables	Categories	n (%)
Absorbent materials
	Disposable pad	1320 (96.6)
	Reusable pad	35 (2.6)
	Cloth from old towel/skirt	7 (0.5)
	Disposable and reusable pad combined	4 (0.3)
Frequency of changing pads per day
	Once a day	113 (8.3)
	2–3 times a day	917 (67.1)
	4–5 times a day	301 (22.0)
	More than 5 times a day	35 (2.6)
Disposable pad accessibility
	Easy to find and affordable	1105 (80.9)
	Difficult due to financial considerations	168 (12.3)
	Difficult due to distance to shops	8 (0.6)
	Difficult due to both financial considerations and distance to shops	44 (3.2)
	Not sure	41 (3.0)
Are you satisfied with your frequency of changing pads?
	Unsatisfied, it is not enough	271 (19.8)
	Neutral, not satisfied and not dissatisfied	275 (20.1)
	Satisfied	820 (60.1)
Do you avoid using the school toilets?
	Yes	883 (64.6)
	No	483 (35.4)
Do you avoid changing pads at school?
	Yes	1061 (77.7)
	No	305 (22.3)
When you change pads at school, where do you throw away the used pads? (multiple answers allowed)
	Toilet bowl	75 (5.5)
	Waste bins at school (including waste bins in the school’s toilets and waste bin in other areas at school)	1000 (73.2)
	Bury (under dirt)	56 (4.1)
	Keep in a plastic bag and bring home	325 (23.8)
	Othersa	32 (2.3)
	I have never changed pads in school	64 (4.7)
What do you do with your underwear?
	I wash and use new underwear daily	1326 (97.1)
	Reuse without washing sometimes	40 (2.9)
How do you clean your reusable pad or cloth?
	Clean water with detergent always	32 (69.6)
	Clean water with detergent sometimes	3 (6.5)
	No response	11 (23.9)
How do you dry your underwear and your reusable pad?
	Unhidden, expose to sunlight	443 (32.4)
	Hidden, unexposed to sunlight	646 (47.3)
	Not sure	157 (11.5)
	No response	120 (8.8)
Have you been absent from school due to menstruation within the last six months?
	Yes	434 (31.8)
	No	932 (68.2)

aOthers include throwing away pads in open areas, bushes, and others.

Characteristics of school toilets

In addition to the girls’ behavior and use of school toilets, a school toilet assessment was administered at the six schools in order to comprehensively and holistically understand the menstrual experiences and hygiene practices of the girls at school. Four of the six schools did not have gender-separated toilets and none of the schools provided toilet paper in the school toilets (Table 5). Moreover, four schools did not have waste bins available in any toilet blocks or toilet cubicles. Despite this, the cleanliness of the school toilets was acceptable on the assessment days.

Table 5

Characteristics of school toilets at six schools in Luang Prabang Province.

Variables	School A	School B	School C	School D	School E	School F
Number of students	2960	552	985	675	956	358
Number of girl students	1359	263	542	383	496	152
Number of toilets	87	27	20	6	4	14
Number of functionable toilets	56	27	20	6	4	14
Number of toilets for girl students	0	10	0	0	0	4
Number of students per toilet	53	20	49	113	239	26
Gender-separated toilet	No	Yes	No	No	No	Yes
Water for cleaning/flushing the toilet bowl	Yes	Yes	Yes	Yes	Yes	Yes
Water for cleaning body after using the toilet	Yes	Yes	No	No	No	Yes
Toilet paper in the toilet	No	No	No	No	No	No
Door latch in each squat toilet	Yes	Yes	Yes	Yes	Yes	Yes
Light bulb in the toilet	Yes	Yes	Yes	Yes	No	No
Waste bin in each toilet block	No	Yes	Yes	No	No	No
Waste bin in the common area of the toilet room	No	Yes	Yes	No	No	No
Waste bin in front of (outside) the toilet	Yes	Yes	Yes	No	No	No
Waste bin around school area	Yes	Yes	Yes	Yes	Yes	Yes
Waste bin cover	No	No	Yes	No	No	No
Hook for hanging belongings	No	No	No	No	No	No
Soap for washing hands	Yes	Yes	No	Yes	No	Yes
Basin for hand washing in or near the toilet	Yes	Yes	Yes	Yes	No	Yes
A clear sign instructing girls to dispose of pads in the waste bin	No	Yes	No	No	No	Yes
Level of cleanliness of the school toilet	Considered clean	Acceptable	Acceptable	Acceptable	Considered clean	Considered clean

Factors associated with school absence among the girls

A logistic regression analysis was performed to identify factors associated with school absence due to menstruation (Table 6). In this study, we found that higher age (age ≥ 16 years old) (Adjusted OR (AOR) = 1.79, 95% CI 1.37–2.34, P < 0.001) and higher allowance (≥ 200,000 LAK per week) (AOR = 2.38, 95% CI 1.16–4.87, P < 0.05) were significantly associated with school absence. Living with relatives (AOR = 0.64, 95% CI 0.43–0.95, P < 0.05) and studying at schools outside the city (AOR = 0.59, 95% CI 0.38–0.90, P < 0.05) were significantly less associated with school absence due to menstruation than living with their parents and schools in the city, respectively. In addition, girls who responded that they were stressed, irritated, and anxious during menstruation were 1.5 times more likely to be absent from school due to menstruation (AOR = 1.55, 95% CI 1.09–2.20, P < 0.05). Girls who experienced dysmenorrhea to the extent that they needed to treat the pain, including painkillers (AOR = 4.79, 95% CI 2.96–7.76, P < 0.001) and other methods (AOR = 2.82, 95% CI 1.86–4.28, P < 0.001), had significantly higher school absence compared to girls who did not use any dysmenorrhea management methods. Furthermore, girls who disposed of their used pads in places other than school’s waste bins were significantly more likely to be absent from school due to menstruation than the others (AOR = 1.34, 95% CI 1.03–1.75, P < 0.05).

Table 6

Binary and multivariate analysis on school absence due to menstruation.

Variables	School absence		OR (95% CI)	AOR (95% CI)
	No (N = 932)	Yes (N = 434)
	n (%)	n (%)
Age
< 16 years old	434 (76.5)	133 (23.5)	1 (reference)	1 (reference)
≥ 16 years old	498 (62.3)	301 (37.7)	1.97 (1.55–2.51)***	1.79 (1.37–2.34)***
Ethno-linguistics
Lao-Tai	619 (68.0)	291 (32.0)	1 (reference)	1 (reference)
Hmong-Mien	162 (65.6)	85 (34.4)	1.12 (0.83–1.50)	1.24 (0.81–1.89)
Mon-Khmer	151 (72.2)	58 (27.8)	0.82 (0.59–1.14)	1.12 (0.72–1.74)
Allowance per week
< 15,000 LAK	144 (72.7)	54 (27.3)	1 (reference)	1 (reference)
20,000–40,000 LAK	305 (71.4)	122 (28.6)	1.07 (0.73–1.56)	1.07 (0.69–1.66)
50,000–100,000 LAK	366 (67.5)	176 (32.5)	1.28 (0.89–1.84)	1.27 (0.81–2.00)
110,000–200,000 LAK	89 (60.5)	58 (39.5)	1.74 (1.10–2.74)*	1.57 (0.89–2.77)
> 200,000 LAK	28 (53.8)	24 (46.2)	2.29 (1.22–4.29)*	2.38 (1.16–4.87)*
Father’s education
Unable to read/write	34 (55.7)	27 (44.3)	1 (reference)	1 (reference)
Primary school	207 (69.7)	90 (30.3)	0.55 (0.31–0.96)*	0.64 (0.33–1.26)
Lower secondary school	156 (67.0)	77 (33.0)	0.62 (0.35–1.10)	0.76 (0.37–1.56)
Upper secondary school	212 (68.2)	99 (31.8)	0.59 (0.34–1.03)	0.64 (0.31–1.32)
Diploma or higher	323 (69.6)	141 (30.4)	0.55 (0.32–0.95)*	0.51 (0.25–1.07)
Mother’s education
Unable to read/write	102 (61.4)	64 (38.6)	1 (reference)	1 (reference)
Primary school	256 (70.1)	109 (29.9)	0.68 (0.46–1.00)*	0.71 (0.44–1.15)
Lower secondary school	188 (69.9)	81 (30.1)	0.69 (0.46–1.03)	0.76 (0.44–1.31)
Upper secondary school	215 (68.9)	97 (31.1)	0.72 (0.49–1.07)	0.86 (0.48–1.54)
Diploma or higher	171 (67.3)	83 (32.7)	0.77 (0.51–1.16)	0.94 (0.50–1.77)
Residence
Live with parents	719 (67.6)	345 (32.4)	1 (reference)	1 (reference)
Live with relatives	130 (72.6)	49 (27.4)	0.79 (0.55–1.12)	0.64 (0.43–0.95)*
Stay at dormitory/rental apartment	83 (67.5)	40 (32.5)	1.00 (0.67–1.50)	0.96 (0.59–1.57)
School area
In Luang Prabang City	758 (66.7)	379 (33.3)	1 (reference)	1 (reference)
Outside Luang Prabang City	174 (76.0)	55 (24.0)	0.63 (0.46–0.88)**	0.59 (0.38–0.91)*
Menstruation knowledge level
Good knowledge	133 (70.0)	57 (30.0)	1 (reference)	1 (reference)
Some knowledge	567 (67.4)	274 (32.6)	1.13 (0.80–1.59)	1.33 (0.91–1.94)
Poor knowledge	232 (69.3)	103 (30.7)	1.04 (0.70–1.53)	1.45 (0.94–2.23)
Mood and emotion during menstruation
None, I feel no change	216 (79.1)	57 (20.9)	1 (reference)	1 (reference)
Stress, irritated, and anxious	716 (65.5)	377 (34.5)	2.00 (1.45–2.74)***	1.55 (1.09–2.20)*
Dysmenorrheal management
No pain or mild pain (use nothing)	207 (85.5)	35 (14.5)	1 (reference)	1 (reference)
Painful, took painkillers	121 (54.8)	100 (45.2)	4.89 (3.13–7.63)***	4.79 (2.96–7.76)***
Painful, used other methodsa	604 (66.9)	299 (33.1)	2.93 (1.99–4.30)***	2.82 (1.86–4.28)***
Do you try to avoid using toilets at school?
No	345 (71.4)	138 (28.6)	1 (reference)	1 (reference)
Yes	587 (66.5)	296 (33.5)	1.26 (0.99–1.61)	1.19 (0.88–1.60)
Do you try to avoid changing pads at school?
No	220 (72.1)	85 (27.9)	1 (reference)	1 (reference)
Yes	712 (67.1)	349 (32.9)	1.27 (0.96–1.68)	1.16 (0.82–1.64)
Type of absorbent materials
Disposable pads only	901 (68.3)	419 (31.7)	1 (reference)	1 (reference)
Othersb	31 (67.4)	15 (32.6)	1.04 (0.56–1.95)	0.98 (0.45–2.15)
Frequency of changing pads
Two times or more	852 (68.0)	401 (32.0)	1 (reference)	1 (reference)
One time only	80 (70.8)	33 (29.2)	0.88 (0.57–1.34)	0.82 (0.50–1.32)
Mode of pad disposal (for disposable pad users)
Only throw in waste bins at the school (both inside and outside school toilet)	539 (70.1)	230 (29.9)	1 (reference)	1 (reference)
Othersc	340 (66.8)	169 (33.2)	1.17 (0.92–1.48)	1.34 (1.03–1.75)*
Commercial pad accessibility
Easily accessible	750 (67.9)	355 (32.1)	1 (reference)	1 (reference)
Some difficulties	182 (69.7)	79 (30.3)	0.92 (0.68–1.23)	0.91 (0.65–1.28)

OR, odds ratio; AOR, adjusted odds ratio; CI, confidence interval.

aOther methods refers to traditional medicines, hot pack on the stomach, and/or two or more methods combined.

bOthers refers to reusable pads, cloths, or disposable pads and reusable pads combined.

cOthers refers to throwing in the toilet bowl, bringing home, burning, and throwing away pads in open areas, bushes, and others.

*P < 0.05,

**P < 0.01,

***P < 0.001.

9,453 LAK = 1 USD as of June 4, 2021.

Discussion

The results of this study showed that 31.8% of secondary school girls missed school due to menstruation within the six months before this study and that there were menstrual knowledge gaps among girls in Luang Prabang Province. In addition, girls who were 16 years old or older, who had a higher allowance > 200,000 LAK per week, and who studied at schools in Luang Prabang City had significantly higher school absence due to menstruation. Girls who lived with relatives had significantly less school absence than girls who lived with their parents. Moreover, girls who chose to dispose of their used pads in places other than school waste bins, girls who used painkillers and other methods to manage their dysmenorrhea, as well as girls who were stressed, irritated, and anxious during menstruation were associated with school absence.

Most secondary school girls (64.5%) reported that they were shocked and/or ashamed when they had their first menstruation. This result may suggest that the girls did not have adequate information to be prepared for their menarche. The Ministry of Education and Sports of Lao PDR includes concise but limited menstrual education in the reproductive health section under the Natural Sciences textbook for secondary school grade 9 [36], where a majority of girls are aged 13–14 years old. In this study, 69.1% of girls reached menarche before grade 9, and only 4.9% obtained precise menstrual information from teachers at school before their menarche. The gap between the menstrual education provision and girl’s age at menarche might result in fear when they reached menarche. In addition, the percentage of girls who had ‘good knowledge’ about menstruation was not higher in girls of grades 10–12 (13.2%) compared to that of girls of grade 9 (18.4%). This demonstrated that girls did not fully understand about menstruation even after they were taught at school. Accurate, sufficient, and timely information is necessary for girls to reduce the fear, shame, and stigma related to menstruation, as well as to encourage their good hygiene practice. Menstrual health should be included in the curriculum of grade 5 (10–11 years old) at elementary school, because only elementary education (grades 1–5) is compulsory for all Lao children [37]. Furthermore, teacher training on reproductive health, especially menstrual health, should be promoted and strengthened to ensure that teaching techniques and contents are well integrated and delivered.

School toilets might be a factor affecting school absence due to menstruation for girls in Luang Prabang Province. In this study, girls from schools in Luang Prabang City were associated with school absence. Girls in the city might feel uncomfortable and lack confidence in practicing good hygiene where school toilets did not meet their needs. Among 64 respondents in this study who admitted that they had never changed pads at school toilets at all, 55 girls (85.9%) went to schools in the city, and 9 girls (14.1%) went to schools outside the city. This was consistent with a systematic review which reported that inadequate sanitation facilities posed challenges for girls to manage their menses with dignity in academic environments [38]. In Lao PDR, the percentage of schools that had basic water supply and sanitation facilities was reported to have improved from 28% in 2000 to 74% in 2017 [39], but there has been no information regarding facilities for menstrual hygiene management and gender-segregated toilets at schools [40]. In this study, four of six schools did not have gender-separated toilets, and did not have waste bins in each toilet block nor in the toilet cubicle. Girl students might feel discomfort and boy students might find out and tease them in the toilet for menstruating [4, 11, 18]. Improved school toilets refer to not only functional toilets but also facilities that are gender-friendly and have necessary items for girls to practice good hygiene [35].

Apart from school toilets, it is reported that dysmenorrhea and mental wellbeing during menstruation were significantly associated with school absence [4, 41]. In this study, girls who took painkillers were 4.79 times more likely to be absent from school, while those using other methods to manage dysmenorrhea were 2.82 times more likely to be absent from schools compared to those who had mild symptoms or did not have dysmenorrhea at all. Painkillers may indicate the severity of the pain where girls cannot conduct their routine activities, including attending school [41, 42]. Qualitative studies in Africa reported that girls were anxious about menstrual leaks onto their clothes and that they had to always be careful and think about it, causing them stress and resulting in them paying less attention to their studies which in turn affected their academic performance [4, 18]. Menstrual hygiene at school should be promoted and menstrual pads and painkillers should be freely available when needed in order to facilitate girls’ participation and sustain their educational performance.

In this study, girls with a higher allowance were more likely to be absent from school due to menstruation than those who had a lower allowance. This is inconsistent with many studies in Africa, which revealed that a lower income household was associated with school absence [4, 9, 18]. Low economic status is also reported as a major risk factor of poor menstrual hygiene management and associated with less use of absorbents and disposable pads in other studies [12, 18, 34, 43]. The inconsistency might be due to menstrual context differences, the condition of school toilets, and the proportion of sanitary pad availability and accessibility in different study settings. Previous studies showed that approximately 35% of girls in Western Ethiopia used disposable pads [4], while only 9% of girls in rural Uganda used disposable absorbents [18]. Reusable pad users and cloth users in Africa might struggle to manage menstruation at schools. In this study, on the other hand, 96.6% of girls used disposable pads and 80.9% of girls could easily access and afford disposable pads. The difference of disposable pad usage between girls in Luang Prabang City (98.3%) and outside the city (88.2%) was small, although Goli et al. reported a geographical disparity in accessing sanitation napkins in India [43]. The mass disposable pad usage in this study might contribute to the relationship between girls’ allowance and school absence. This suggests that school absence due to menstruation might not be directly linked to socio-economic status in Lao PDR.

This study has some limitations. First, the cross-sectional data cannot identify any causal effect relationship among the factors. Second, the questionnaire required self-reported absenteeism, and some girls might be reluctant to answer this question honestly or might not remember clearly. As 117 girls who did not respond to the question about school absence were excluded from the analysis, the prevalence of school absenteeism in this study might be underestimated. Third, due to the nature of a multiple-choice questionnaire, the true nature of the experiences and practices among girls might not be shown, such as their reasons behind school toilet avoidance. Lastly, we included only girls who could attend secondary school and most of them had easy access to and used disposable pads. Further studies that include girls out of school and use qualitative research methods are necessary to broaden the understanding regarding the challenges in managing menstrual hygiene among Lao girls.

Conclusion

In this study, the proportion of school absence due to menstruation among secondary school girls in Luang Prabang Province was 31.8%. Factors associated with school absence due to menstruation (age ≥ 16 years old, higher income, schools in the city, menstrual anxiety, dysmenorrhea, and disposing used pads in places other than school’s waste bins) suggest that school absence due to menstruation might not be directly linked to socio-economic status rather than feeling uncomfortable and a lack confidence in practicing good hygiene at school toilets. Although the association between school toilets and school absence was not examined, the results of this study suggest that school toilets should be gender-separated and equipped with essential waste bins in the toilet. Furthermore, menstrual education should start at elementary school and teacher training on reproductive health, especially menstrual health, should be promoted.

31 Aug 2021

PONE-D-21-23049

Menstrual health and factors associated with school absence among secondary school girls in Luang Prabang Province, Lao People’s Democratic Republic: A cross-sectional study

PLOS ONE

Dear Dr. Yamamoto,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Considering my own reading and reviewers opinion, I am recommending a minor revision for this paper.  Along with reviewers suggestions, I recommend authors to interpret their findings in comparative perspective with global literature to reach the global readers. I have provided a few references to consult in this regard.

Malhotra, A., Goli, S., Coates, S., & Mosquera-Vasquez, M. (2016). Factors associated with knowledge, attitudes, and hygiene practices during menstruation among adolescent girls in Uttar Pradesh. Waterlines, 277-305.

Goli, S., Sharif, N., Paul, S., & Salve, P. S. (2020). Geographical disparity and socio-demographic correlates of menstrual absorbent use in India: A cross-sectional study of girls aged 15–24 years. Children and Youth Services Review, 117, 105283.

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Additional Editor Comments:

Considering my own reading and reviewers opinion, I am recommending a minor revision for this paper. Along with reviewers suggestions, I recommend authors to interpret their findings in comparative perspective with global literature to reach the global readers. I have provided a few references to consult in this regard.

Malhotra, A., Goli, S., Coates, S., & Mosquera-Vasquez, M. (2016). Factors associated with knowledge, attitudes, and hygiene practices during menstruation among adolescent girls in Uttar Pradesh. Waterlines, 277-305.

Goli, S., Sharif, N., Paul, S., & Salve, P. S. (2020). Geographical disparity and socio-demographic correlates of menstrual absorbent use in India: A cross-sectional study of girls aged 15–24 years. Children and Youth Services Review, 117, 105283.

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Reviewer #1: I appreciate the opportunity to review this manuscript on menstrual health and factors associated with school absence among secondary school girls in Luang Prabang Province, Lao People’s Democratic Republic. This is a very interesting and well written paper, providing much needed evidence on effect of menstruation on school going girls. I recommend the paper for publication. However, I have few observations which I think the authors can incorporate in the final stage.

• The authors may highlight the important factors associated with school absence due to menstruation with statistical significant values (Odds) in the abstract.

• Use of different types of menstrual absorbent materials could have been also related to school absence. Therefore, it can be included in the regression model.

• The authors should include the limitation of self-reported absenteeism at the end of Discussion section.

Reviewer #2: 1. A brief introduction about the needs and availability/unavailability of the facilities in schools would depict the introduction in a better way.

2. The methodology is not clear. The information on how the schools were selected is missing.

3. How the consent was sought is not clear. How the consent was sought from parents is not clear.

4. “Each parent’s education was classified into five levels”- There is no need to write ‘each parent’s education’ drop the word ‘each.’ (See line 125)

5. Line 146-147 states – “Questions to identify the level of menstrual knowledge and menstrual hygiene practices 147 were retrieved from literature reviews [4, 8, 9, 30].” None of the four references are from the local context. It would be better if authors could include a few local study for citation, if available.

6. Line 147-150. Authors describe about the five questions related to menstruation. This is just a query- whether these questions are self-derived or adopted from somewhere else. Please clarify.

7. It is suggested to use the same terminology everywhere in the manuscript. Authors have used girls/student interchangeably.

8. Conclusion section seems more of the result section. This needs more insights.

Reviewer #3: Overall comment: The study explores the menstrual knowledge and menstrual hygienepractices among schools girls. Most important aspects surrounding this area of research has been covered. Improvement on certain points will make the article publishable.

Introduction: Literature can be added on fertility association with menstrual health, and also menstrual hygiene related diseases.

Materials and Methods: The sampling procedure needs to be added, how the authors have selected the six schools from 45 schools. The dependent and independent variable can be segregated in the variable description part.

Line 174: The authors have considered statistical significance at 5% as written in the data analysis section, but further in results part they have also considered significance at 1% and 0.1% as well. So that can be mentioned too in the data analysis section.

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Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes: Sampurna Kundu

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12 Oct 2021

We would like to thank the editor and the reviewers for reviewing our manuscript. We have revised the manuscript according to your comments, which were very helpful. The revised manuscript has been proofread by a native English speaker. The revisions have been completed and the responses are as follows.

Editor

1. Considering my own reading and reviewer’s opinion, I am recommending a minor revision for this paper. Along with reviewers’ suggestion, I recommend authors to interpret their findings in comparative with global literature to reach the global readers. I have provided a few references to consult in this regard.

- Malhotra, A., Goli, S., Coates, S., & Mosquera-Vasquez, M. (2016). Factors associated with knowledge, attitudes, and hygiene practices during menstruation among adolescent girls in Uttar Pradesh. Waterlines, 277-305.

- Goli, S., Sharif, N., Paul, S., & Salve, P. S. (2020). Geographical disparity and socio-demographic correlates of menstrual absorbent use in India: A cross-sectional study of girls aged 15–24 years. Children and Youth Services Review, 117, 105283.

Thank you very much for your recommendation. After reviewing both papers of the studies conducted in India, we have used the results of these papers to compare with the results of our study as follows.

Lines 351-353: “Low economic status is also reported as a major risk factor of poor menstrual hygiene management and associated with less use of absorbents and disposable pads in other studies [12, 18, 34, 43].”

Line 359-362: “The difference of disposable pad usage between girls in Luang Prabang City (98.3%) and outside the city (88.2%) was small, although Goli et al reported the geographical disparity in accessing sanitation napkins in India [43].”

Reviewer #1:

1. The authors may highlight the important factors associated with school absence due to menstruation with statistical significant values (Odds) in the abstract.

Lines 38-45: We have added AOR and 95% CI for factors associated with school absence in the abstract as follows, “Factors associated with school absence due to menstruation were age ≥ 16 years old (AOR = 1.79, 95% CI 1.37-2.34), higher income (AOR = 2.38, 95% CI 1.16-4.87), menstrual anxiety (AOR = 1.55, 95% CI 1.09-2.20), using painkillers (AOR = 4.79, 95% CI 2.96-7.76) and other methods (AOR = 2.82, 95% CI 1.86-4.28) for dysmenorrhea, and disposing used pads in places other than the school’s waste bins (AOR = 1.34, 95% CI 1.03-1.75). Living with relatives (AOR = 0.64, 95% CI 0.43-0.95) and schools outside the city (AOR = 0.59, 95% CI 0.38-0.90) were significantly less associated with school absence.”

2. Use of different type of absorbent materials could have been also related to school absence. Therefore, it can be included in the regression model.

Table 6: We appreciate this comment and we understood that absorbent materials should be included in the regression models. Factors associated with school absence due to menstruation were not changed by adding the variable “type of absorbent materials” in binary and multivariate logistic regression analyses. We have revised accordingly Table 6.

3. The author should include the limitation of self-reported absenteeism at the end of Discussion section.

Lines 366-370: A limitation of self-reported absenteeism has been added. “Second, the questionnaire required self-reported absenteeism, and some girls might be reluctant to answer this question honestly or might not remember clearly. As 117 girls who did not respond to the question about school absence were excluded from the analysis, the prevalence of school absenteeism in this study might be underestimated.”

Reviewer #2:

1. A brief introduction about the needs and availability/unavailability of the facilities in school would depict the introduction in a better way.

Lines 79-81: Information on the available facilities in schools in Laos was added as follows, “In Lao People’s Democratic Republic (Lao PDR), approximately 59% of schools did not have sanitation facilities and 61% of schools did not have improved water source in 2008 [28]. Therefore, many students had to return home to use the toilet or defecate in the forest.”

2. The methodology is not clear. The information on how the schools were selected is missing.

Lines 103-109: We are sorry for not clearly explaining how the six schools were selected in the method section. We decided to select four schools in the city and two schools out of the city (in districts). A lottery method was used for random sampling of three schools in the city. However, two schools out of the city were chosen according to easy accessibility including road conditions and the distance from the center of the city to the schools. We have revised the manuscript as follows, “Six schools were selected from the 45 public secondary schools. Four schools (Santiphab secondary school, Phanluang secondary school, Pongkham secondary school, and Pasathipatai secondary school) were selected from 24 schools in Luang Prabang City (Luang Prabang District) by simple random sampling using a lottery method. Two schools were selected from 21 schools in 11 districts, outside the city, by convenience sampling considering their accessibility; Chomphet secondary school in Chomphet District, and Sobjaek secondary school in Pakxeng District.”

3. How the consent was sought is not clear. How the consent was sought from the parents is not clear.

Lines 189-192: To the best of our knowledge, in Lao PDR, people who are 18 or older are legally adults. As shown in Table 1, 22.1% of the students did not live with their parents; 13.1% lived with relatives and 9.0% lived at dormitory/rental apartment. Therefore, in this study, we obtained informed consent from guardians including parents, relatives, and teachers, when girl students were younger than 18 years old. We provided the consent forms for guardians three days before the data collection. We have added as follows, “For all participants aged under 18 years old, written informed consent was also obtained from their guardians including parents, relatives, and teachers before the data collection. The data collection team visited the schools and distributed the forms for guardians three days before the data collection.”

4. “Each parent’s education was classified into five levels” – there’s no need to write ‘each parent’s education’, drop the word ‘each’.

Lines 147-148: We have revised the sentence and dropped the word ‘Each’, as following: “Parental education was classified into five levels: no education, primary school, lower secondary school, upper secondary school, and diploma level or higher.”

5. Line 146-147 states – “Questions to identify the level of menstrual knowledge and menstrual hygiene practices 147 were retrieved from literature reviews [4, 8, 9, 30].” None of the four references are from the local context. It would be better if authors could include a few local studies for citation, if available.

Lines 168-169: There are not many papers concerning quantitative studies on menstrual knowledge and menstrual hygiene practice in Southeast Asia. When we were plannning this research from late 2019 to early 2020, most of the literature searched by the PubMed library were from Africa and South Asia. Cultures, beliefs, and practices in Africa and South Asia are very different from those in Lao PDR. We cited a paper of a study conducted in Bhutan (previously listed as reference 30) but we have also added a paper from India in the references (reference number 34) as follows, “Questions to identify the level of menstrual knowledge and menstrual hygiene practices were retrieved from literature reviews [4, 8, 9, 33, 34].”

6. Line 147-150. Authors describe about the five questions related to menstruation. This is just a query – whether these question s are self-derived or adopted from somewhere else. Please clarify.

Lines 169-170: We retrieved the five questions about menstruation knowledge from the publication “Knowledge, attitude and practices of menstrual hygiene management of adolescent school girls and nuns in Bhutan” by the Ministry of Education of Bhutan and UNICEF. This is a report of the survey conducted in Bhutan and explained clearly about the used tool for the survey and the result of the menstrual knowledge using these five questions.We have added the reference number as follows, “Five questions concerning menstruation were used to evaluate girl’s knowledge [33]”

7. It is suggested to use the same terminology everywhere in the manuscript. Authors have used girls/student interchangeably.

We have decided to use “girls” and revised the manuscript.

8. Conclusion section seems more of the result section. This needs more insights.

Lines 379-383: We have reduced the summary of the results and added an interpretation of the results in the conclusion section as follows, “Factors associated with school absence due to menstruation (age ≥ 16 years old, higher income, schools in the city, menstrual anxiety, dysmenorrhea, and disposing used pads in places other than school’s waste bins) suggest that school absence due to menstruation might not be directly linked to socio-economic status rather than feeling uncomfortable and a lack confidence in practicing good hygiene at school toilets.”

Reviewer #3:

1. Introduction: Literature can be added on fertility association with menstrual health, and also menstrual hygiene related diseases.

Lines 60-64: We have added sentences about the association between poor menstrual hygiene management and infertility in the introduction section, citing two more papers as follows, “Poor menstrual hygiene management is associated with poor mental health and poor physical health, such as urinary tract infection and bacterial vaginosis [12-15]. Bacterial vaginosis may cause reproductive tract infections and lead to pelvic inflammatory disease [14, 16], and unhygienic practices during menstruation is reported to be one of risk factors of secondary infertility [16, 17].”

2. Materials and Methods: The sampling procedure needs to be added, how the authors have selected the six schools from 45 schools. The dependent and independent variable can be segregated in the variable description part.

Lines 103-109: We are sorry for not clearly explaining how the six schools were selected in the method section. We decided to select four schools in the city and two schools out of the city (in districts). A lottery method was used for random sampling of three schools in the city. However, two schools out of the city were chosen according to easy accessibility including road conditions and the distance from the center of the city to the schools. We have revised the manuscript as follows, “Six schools were selected from the 45 public secondary schools. Six schools were selected from the 45 public secondary schools. Four schools (Santiphab secondary school, Phanluang secondary school, Pongkham secondary school, and Pasathipatai secondary school) were selected from 24 schools in Luang Prabang City (Luang Prabang District) by simple random sampling using a lottery method. Two schools were selected from 21 schools in 11 districts, outside the city, by convenience sampling considering their accessibility; Chomphet secondary school in Chomphet District, and Sobjaek secondary school in Pakxeng District.”

Lines 137-179: We have made a new paragraph of “Variables” and moved our explanation about dependent and independent variables from the paragraph of “Data collection instrument and procedure” to the paragraph of “Variables.”

3. Line 174: The authors have considered statistical significance at 5% as written in the data analysis section, but further in the results part they have also considered significance at 1% and 0.1% as well. So that can be mentioned too in the data analysis section.

Lines 184-185: P value < 0.05 was considered as statistically significant in all analyses of this study. In some tables, we used symbols (** and ***) to understand when P value was < 0.01 and < 0.001 as the same as other papers.

Submitted filename: Response to reviewers.docx

Click here for additional data file.

26 Nov 2021

Menstrual health and factors associated with school absence among secondary school girls in Luang Prabang Province, Lao People’s Democratic Republic: A cross-sectional study

PONE-D-21-23049R1

Dear Dr. Yamamoto,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Srinivas Goli, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Considering my own reading and reviewers suggestion, I am going with a decision of accept.

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Reviewer #1: All comments have been addressed

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: (No Response)

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Reviewer #1: No

3 Dec 2021

PONE-D-21-23049R1

Menstrual health and factors associated with school absence among secondary school girls in Luang Prabang Province, Lao People’s Democratic Republic: A cross-sectional study

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