Abstract
Objective: To assess the relationship between the first-trimester maternal serum pregnancy-associated plasma protein-A (PAPP-A) levels and pregnancies complicated by preterm delivery. Materials and Methods: The correlation between PAPP-A levels and gestational age at delivery was analyzed by linear regression. The probabilities of low PAPP-A multiples of the median (MoM) levels between preterm delivery and control population were analyzed by logit model. Results: A positive correlation was noted between the first-trimester PAPP-A MoM levels and gestational age at delivery between 34-38 weeks (p < 0.001). Lower PAPP-A MoM level had a significantly higher likelihood of preterm delivery (p < 0.05). When preterm premature rupture of membranes (PPROM) and preterm labor (PTL) were analyzed separately, there was an increasing likelihood of PPROM with decreasing PAPP-A MoM levels (p < 0.05), but not for PTL with intact membranes. Conclusion: Low maternal serum PAPP-A levels during the first trimester may reflect a trophoblast invasion defect in the maternal-fetal interface, resulting in subsequent preterm delivery, particularly in those of PPROM.