Zeinab Hemati1,2, Mojtaba Keikha3, Roya Riahi2, Seyede Shahrbanoo Daniali2, Masoumeh Goudarzi2, Roya Kelishadi4. 1. Nursing and Midwifery Care Research Center, Faculty of Nursing and Midwifery, Isfahan University of Medical Sciences, Isfahan, Iran. 2. Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran. 3. Department of Public Health, Sirjan School of Medical Sciences, Sirjan, Iran. 4. Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran. roya.kelishadi@gmail.com.
Abstract
BACKGROUND: Prenatal factors might have some health impacts later in life. This study aims to systematically review the current literature on the association between season and month of birth with birth weight as well as with weight status in childhood. METHODS: The search process was conducted in electronic databases, including papers published until April 2019 in ISI Web of Science, PubMed, Scopus, and Google Scholar. The following search strategy was used with MeSH terms: ("Seasons"[Mesh]) AND ("Obesity"[Mesh] OR "Pediatric Obesity"[Mesh] OR "Obesity, Abdominal"[Mesh] OR "Overweight"[Mesh] OR "Birth Weight"[Mesh] OR "Body Height"[Mesh]). After the selection process, 50 papers were included in this systematic review. RESULTS: This review showed that individuals who are born in cold season (winter month) have higher body mass index (BMI) and weight in childhood. Birth in March was associated with lower weight and BMI in boys according to most studies. All studies, except one of them, showed that season/month of birth was not associated with birth weight. CONCLUSIONS: This systematic review confirms a relationship between season and month of birth with birth weight and body size in childhood; however, the impact of confounding factors, for example, vitamin D status, should be considered in the underlying pathway of this association. IMPACT: The results provide evidence for the effect of season and month of birth on body size in childhood. Our systematic review suggests that there is no pattern between birth weight and season/month of birth, and the occurrence of low birth weight was more frequent among infants who were born in summer than others. Further research should focus on identifying the impact of confounding factors, for example, vitamin D status in the underlying pathway of this association. There was response to the controversial findings about the effect of environment factors, such as season and month of birth, and future anthropometric indices, such as obesity, weight, height, and birth weight. Obesity is a complex and multifactorial disorder; the findings of the current study would be useful in determining the relationship pathway between the season and the month of birth with other underlying factors for childhood obesity.
BACKGROUND: Prenatal factors might have some health impacts later in life. This study aims to systematically review the current literature on the association between season and month of birth with birth weight as well as with weight status in childhood. METHODS: The search process was conducted in electronic databases, including papers published until April 2019 in ISI Web of Science, PubMed, Scopus, and Google Scholar. The following search strategy was used with MeSH terms: ("Seasons"[Mesh]) AND ("Obesity"[Mesh] OR "Pediatric Obesity"[Mesh] OR "Obesity, Abdominal"[Mesh] OR "Overweight"[Mesh] OR "Birth Weight"[Mesh] OR "Body Height"[Mesh]). After the selection process, 50 papers were included in this systematic review. RESULTS: This review showed that individuals who are born in cold season (winter month) have higher body mass index (BMI) and weight in childhood. Birth in March was associated with lower weight and BMI in boys according to most studies. All studies, except one of them, showed that season/month of birth was not associated with birth weight. CONCLUSIONS: This systematic review confirms a relationship between season and month of birth with birth weight and body size in childhood; however, the impact of confounding factors, for example, vitamin D status, should be considered in the underlying pathway of this association. IMPACT: The results provide evidence for the effect of season and month of birth on body size in childhood. Our systematic review suggests that there is no pattern between birth weight and season/month of birth, and the occurrence of low birth weight was more frequent among infants who were born in summer than others. Further research should focus on identifying the impact of confounding factors, for example, vitamin D status in the underlying pathway of this association. There was response to the controversial findings about the effect of environment factors, such as season and month of birth, and future anthropometric indices, such as obesity, weight, height, and birth weight. Obesity is a complex and multifactorial disorder; the findings of the current study would be useful in determining the relationship pathway between the season and the month of birth with other underlying factors for childhood obesity.
Authors: Boyd A Swinburn; Gary Sacks; Kevin D Hall; Klim McPherson; Diane T Finegood; Marjory L Moodie; Steven L Gortmaker Journal: Lancet Date: 2011-08-27 Impact factor: 79.321
Authors: John J McGrath; Douglas Keeping; Sukanta Saha; David C Chant; Daniel E Lieberman; Michael J O'Callaghan Journal: Early Hum Dev Date: 2005-07 Impact factor: 2.079