Decreased first trimester PAPP-A is a predictor of adverse pregnancy outcome

Objective Low levels of maternal serum pregnancy associated plasma protein‐A (PAPP‐A) have been linked to chromosome anomalies such as trisomy 21, 13 and 18, triploidy and sex chromosome aneuploidy. Low levels of PAPP‐A have also been implicated in spontaneous miscarriage. The purpose of this study was to evaluate whether low levels of first trimester PAPP‐A are predictive of other adverse pregnancy outcomes. Study design The study included patients with singleton pregnancies who underwent combined first trimester screening using nuchal translucency (NT) and maternal serum free β‐human chorionic gonadotrophin (free β‐hCG) and PAPP‐A at 10–13 weeks' gestation. Patients with chromosome aberrations or fetal anomalies were excluded. Serum marker levels were expressed as gestational age‐specific multiples of the median (MoMs). The incidences of various adverse pregnancy outcomes (spontaneous preterm labor, fetal growth restriction (FGR), proteinuric and non‐proteinuric pregnancy induced hypertension (PIH), intrauterine fetal demise, oligohydramnios, spontaneous miscarriage and placental abruption) were evaluated, according to maternal PAPP‐A MoM levels. Results Of the 1622 patients in the study, pregnancy complications were observed in 184 (11.3%). Patients with PAPP‐A ⩽0.25 MoM had significantly higher rates of FGR (RR = 3.12), proteinuric PIH (RR = 6.09), spontaneous miscarriage (RR = 8.76). No statistically significant differences were noted for other adverse outcomes evaluated Women with PAPP‐A ⩽0.50 MoM also had significantly higher rates of FGR (RR = 3.30) and spontaneous miscarriage (RR = 3.78). Conclusions We conclude that decreased levels of first trimester maternal serum PAPP‐A are predictive not only of chromosome anomalies but also of adverse pregnancy outcome. Copyright © 2002 John Wiley & Sons, Ltd.