Value of Pregnancy-Associated Plasma Protein-A for Predicting Adverse Pregnancy Outcome

Background: It is suggested that pregnancy-associated plasma protein-A (PAPP-A) levels below the fifth percentile or less than 0.4 multiples of the median (MoMs) during the first trimester are closely associated with higher risk for neonatal abnormalities. We assessed the value of PAPP-A within the first trimester for predicting pregnancy outcome.

Methods: In a historical cohort study, we assessed 8460 consecutive pregnant women recruited for chromosomal abnormalities screening within the first trimester at Fertility Infertility and Perinatology Research Center, in Ahvaz Jundishapur University of Medical Sciences between April 2014 and April 2015. The women were categorized into two groups: pregnant women with PAPP-A levels below 0.4 multiples of MOM (n = 237) and those with higher levels of PAPP-A (n = 237).

Results: The median value of MOM PAPP-A was 0.82 ± 0.78, with 237 women having MOM PAPP-A lower than 0.4. Compared to women with MOM PAPP-A higher than 0.4, those with lower MOM PAPP-A had higher mean age, lower gestational age and lower birth weight. The prevalence of small for gestational age (SGA) was higher in women with MOM PAPP-A <0.4 compared to others. According to the ROC curve analysis, MOM PAPP-A <0.4 had a high value for predicting SGA. Best cutoff value for MOM PAPP-A to predict SGA was shown to be 0.25, yielding a sensitivity of 84.7% and a specificity of 68.6.

Conclusion: Measuring the serum level of MOM PAPP-A during the first trimester is a valuable marker for predicting adverse outcomes of pregnancy such as SGA.