Low Pregnancy-Associated Plasma Protein A as a Predictor of Delivery Timing in Intrauterine Growth Restriction and Fetal Growth Variations: A Prospective Study

Open Access

Abstract

Background: Low pregnancy-associated plasma protein-A (PAPP-A) reflects impaired placental function and has been associated with fetal growth abnormalities and adverse pregnancy outcomes. However, its relationship with delivery timing among pregnancies complicated by intrauterine growth restriction (IUGR) and fetal growth variations remains insufficiently characterized. Aim of the study: To determine the association of low PAPP-A with delivery timing in pregnancies complicated by IUGR and fetal growth variations. Methods & Materials: A prospective observational study was conducted among 96 pregnant women with suspected or confirmed IUGR or fetal growth variation at a tertiary-level hospital in Bangladesh. Maternal, obstetric, fetal, biochemical, and delivery data were collected prospectively until delivery. Serum PAPP-A was expressed as multiples of the median (MoM), with <0.4 MoM categorized as low. Delivery timing was classified as <34, 34-36, and ≥37 weeks, and multivariable logistic regression was performed to identify factors independently associated with preterm delivery. Results: The mean maternal age was 27.1±4.6 years, and the mean gestational age at enrollment was 32.5±2.7 weeks. IUGR was present in 60.4% of participants, while 38.5% had abnormal umbilical artery Doppler findings. Low PAPP-A was identified in 40.6% of participants, with a mean PAPP-A level of 0.58±0.31 MoM. Overall, 58.3% delivered preterm, including 27.1% before 34 weeks. Delivery timing differed significantly by PAPP-A status (p=0.003), with delivery before 34 weeks occurring in 43.6% of women with low PAPP-A compared with 15.8% with normal PAPP-A. Low PAPP-A was independently associated with preterm delivery (aOR 4.36, 95% CI 1.65-11.54; p=0.003), alongside abnormal umbilical artery Doppler and IUGR. Conclusion: Low PAPP-A was independently associated with earlier delivery and preterm birth among pregnancies complicated by IUGR and fetal growth variations. Pregnancy-associated plasma protein-A; PAPP-A; intrauterine growth restriction; fetal growth restriction; preterm delivery