Chunxiang Qin1,2, Chunmei Mi1, Aibin Xia1, Wei-Ti Chen3, Chunxia Chen1, Ying Li4, Yao Li2, Wenhui Bai2, Siyuan Tang2. 1. Obstetrical Department, The Third Xiangya Hospital, Central South University, Changsha, China. 2. Xiangya School of Nursing, Central South University, Changsha, China. 3. Yale School of Nursing, Yale University, New Haven, CT, USA. 4. Neonatology Department, The Third Xiangya Hospital, Central South University, Changsha, China.
Abstract
BACKGROUND: After China's One-child Policy was replaced with the Two-child Policy in 2013, the rate of second pregnancies with a longer inter-pregnancy interval (IPI) has suddenly increased in that country; however, the effect of long IPIs (≥49 months) on perinatal outcomes remains unreported. METHODS: This was a retrospective cohort study in China from July 2015 through June 2016. We used univariate and multivariate logistic regression models to test the associations among IPI, maternal age, and perinatal outcome (preterm delivery, term low birthweight, and small-for-gestational age). We included baseline factors and variables with biological plausibility as confounders. RESULTS: Our analytic sample included 3309 second pregnancies. The mean IPI was 75.36 months. Compared with second pregnancies with a short IPI of 7-24 months, those with long IPIs had higher adjusted odds ratios (ORs) of preterm delivery (1.70-2.00 [95% CI 1.20-3.33]) and term low birthweight (2.16-2.68 [1.10-6.17]), but not small-for-gestational age. The mean maternal age at current delivery was 32.0 years. Compared with the reference group (25-29 years), second pregnancies for the oldest maternal age group (≥35 years) showed no statistically significant increased ORs for adverse perinatal outcomes. CONCLUSION: Long IPI is a significant contributor to preterm delivery and term low birthweight. Health care providers need to pay close attention to preterm delivery prevention and fetal growth during prenatal care for second pregnancies where the mothers have long IPIs.
BACKGROUND: After China's One-child Policy was replaced with the Two-child Policy in 2013, the rate of second pregnancies with a longer inter-pregnancy interval (IPI) has suddenly increased in that country; however, the effect of long IPIs (≥49 months) on perinatal outcomes remains unreported. METHODS: This was a retrospective cohort study in China from July 2015 through June 2016. We used univariate and multivariate logistic regression models to test the associations among IPI, maternal age, and perinatal outcome (preterm delivery, term low birthweight, and small-for-gestational age). We included baseline factors and variables with biological plausibility as confounders. RESULTS: Our analytic sample included 3309 second pregnancies. The mean IPI was 75.36 months. Compared with second pregnancies with a short IPI of 7-24 months, those with long IPIs had higher adjusted odds ratios (ORs) of preterm delivery (1.70-2.00 [95% CI 1.20-3.33]) and term low birthweight (2.16-2.68 [1.10-6.17]), but not small-for-gestational age. The mean maternal age at current delivery was 32.0 years. Compared with the reference group (25-29 years), second pregnancies for the oldest maternal age group (≥35 years) showed no statistically significant increased ORs for adverse perinatal outcomes. CONCLUSION: Long IPI is a significant contributor to preterm delivery and term low birthweight. Health care providers need to pay close attention to preterm delivery prevention and fetal growth during prenatal care for second pregnancies where the mothers have long IPIs.
Authors: Alejandra Rodríguez-Fernández; Marcela Ruíz-De la Fuente; Ximena Sanhueza-Riquelme; Julio Parra-Flores; María Dolores Marrodán; Eduard Maury-Sintjago Journal: Children (Basel) Date: 2022-06-28