Risk Factors for Adverse Pregnancy Outcomes among Zhuang Ethnic Pregnant Women: A Cohort Study in Guangxi, China.

Risk factors for adverse pregnancy outcomes among Zhuang ethnic pregnant women are unclear. This study analyzed the incidence and risk factors related to preterm birth (PB), low birth weight (LBW) and macrosomia in Zhuang population. We conducted a prospective cohort study of 9965 Zhuang pregnancy women in Guangxi, China. Information on mothers and newborns was obtained by using questionnaires and referring to medical records. Multivariate logistic regression analyses were used to evaluate the association between related factors and adverse pregnancy outcomes. Our results showed that the incidence of PB, LBW and macrosomia in Zhuang people was 5.55%, 5.64% and 2.19%, respectively. Maternal age ≥36 years (OR=2.22, 95% CI: 1.51-3.27) was related to a higher incidence of PB. Those with pre-pregnancy body mass index (BMI) <18.5 kg/m (OR=1.91, 95% CI: 1.45-2.51), and had a female fetus (OR=1.74, 95% CI: 1.36-2.23) were more likely to have LBW infants. Maternal age between 31 and 35 years (OR=1.76, 95% CI: 1.03-2.99) and pre-pregnancy overweight or obesity (OR=1.79, 95% CI: 1.15-2.80) were associated with a higher risk of macrosomia. The protective factors of macrosomia were maternal pre-pregnancy BMI <18.5 kg/m (OR=0.30, 95% CI: 0.15-0.60) and female fetus (OR=0.41, 95% CI: 0.28-0.59). Our study provided a reference for maternal and childcare administration among Zhuang population.