Maternal HDL-c levels are associated with preterm birth and small for gestational age: A prospective study in China

Abstract Background: Evidence suggests that maternal HDL-c levels are associated with preterm birth (PTB) and small for gestational age (SGA). However, existing evidence remains controversial. We aimed to explore the associations of maternal HDL-c levels with PTB and SGA in China.Method: A prospective study that included 1068 pregnant women was conducted in 2017. The concentrations of high-density lipoprotein cholesterol (HDL-c) were analyzed in early, middle, and late pregnancy as continuous variables and categorical variables (by percentile groups). Data on gestational age, as well as the weight and length of the neonates were recorded after delivery. Multivariable logistic regression models were used to estimate the associations between maternal HDL-c levels and PTB and SGA. Result:PTB and SGA occurred in 3.0% and 8.1% of births. Mean maternal HDL-c levels in early pregnancy was equal to that in middle pregnancy (1.67 vs. 1.66 mmol/L, p = 0.309), but decreased slightly from middle pregnancy to late pregnancy (1.66 vs. 1.52mmol/L, p < 0.001). In middle pregnancy, every unit elevation of HDL-c was positively associated with SGA (OR = 2.57, 95 % CI: 1.23-5.35). In late pregnancy, every unit elevation of HDL-c reduced the risk of PTB (OR = 0.12, 95 % CI: 0.03-0.58), but increased the risk of SGA (OR = 2.59, 95 % CI: 1.22-5.47). In early pregnancy, low (<25th percentile) HDL-c was positively associated with PTB (OR = 2.56, 95 % CI: 1.11-5.09), and high (>75th percentile) HDL-c was positively associated with SGA (OR = 2.92, 95 % CI: 1.69-5.04), compared with referent (25th-75th percentile) HDL-c.Conclusion:Maternal high levels of HDL-c could reduce the risk of PTB but increase the risk of SGA. There may exist appropriate reference range for maternal HDL-c in early pregnancy. Maternal HDL-c levels should be monitored regularly during pregnancy to decrease adverse perinatal outcomes.