Associations between maternal mid-pregnancy apolipoprotein A-1, apolipoprotein B, apolipoprotein B/apolipoprotein A-1 ratio and preterm birth

Background and aims Elevated lipid levels during pregnancy have been shown to be related to the risk of preterm birth. Despite the importance of apolipoprotein (Apo) in lipid metabolism and transportation, evidence regarding apolipoprotein levels during pregnancy and preterm birth is still limited. Therefore, we aim to investigate the associations between maternal ApoA-1, ApoB, ApoB/ApoA-1 ratio and preterm birth. Materials and meth Data were extracted from the information system of Guangdong Women and Children Hospital. Lipoprotein levels were tested using Beckman Coulter AU5800 in mid-pregnancy at a median gestational age of 18 w. Maternal serum ApoB, ApoA-1 and ApoB/ApoA-1 ratio were categorized into tertiles. Logistic regression models were performed to evaluate the odds ratios and 95% confidence intervals for preterm birth. Results A total of 5,986 maternal-newborn pairs were included in this study. The rate of preterm birth was 5.7% (n = 344). The multivariate-adjusted ORs (95% CI) of preterm birth were 1.51 (1.06, 2.10) for individuals with high ApoB (>90th), 0.63 (0.38, 0.99) for those with low ApoB (<10th), and 1.64 (1.18, 2.24) for those with high ApoB/ApoA-1 (>90th). Subgroup analyses showed that the association of ApoB and preterm birth was only significant among women with pre-pregnancy BMI 18.5-24 kg/m2 (OR = 1.36, 95% CI: 1.12–1.65), age at delivery ≥ 35 years (OR = 1.43, 95% CI: 1.12–1.83). Conclusion Elevated maternal ApoB level and ApoB/ApoA-1 ratio during mid-pregnancy were related to increased risk of preterm birth. Monitoring maternal serum apolipoprotein levels may help to identify the high-risk population of preterm birth.