Predicting SGA neonates using first-trimester screening: influence of previous pregnancy's birthweight and PAPP-A MoM

J Matern Fetal Neonatal Med. 2016 Sep;29(18):2962-7. doi: 10.3109/14767058.2015.1109622. Epub 2015 Dec 15.


Objective: Investigating the proportions of anamnestic and biochemical variables of the previous and current pregnancies for the prediction of small for gestational age (SGA) neonates in the current pregnancy.

Methods: In this observational retrospective study, 45 029 pregnancies were examined, including 3862 patients with more than one pregnancy. Odds ratios for SGA using anamnestic parameters and pregnancy-associated plasma protein A (PAPP-A) values from all pregnancies were estimated by using a logistic regression model.

Results: There were 2552 (5.7%) SGA neonates. Two threshold PAPP-A values were identified at 0.15 MoM and 0.33 MoM with probabilities for SGA of 23% and 17%, respectively. A previous SGA < 10th centile and a current PAPP-A MoM value < 5th centile result in odds ratios of 4.8 (95% CI: 3.5-6.5) and 3.0 (95% CI: 1.8-5.0), respectively. The parameters' combined odds ratio is 14.1 (95% CI: 3.9-50.3) with a number needed to screen of ten for one SGA neonate at a detection rate of 37%.

Conclusion: Information on previous pregnancies affected by SGA and a current pregnancy's low PAPP-A value are reliable predictors for a SGA delivery. First-trimester biochemical analysis should be maintained to detect women at risk for delivering a SGA neonate.

Keywords: Maternity care; obstetrics; prenatal diagnosis.

Publication types

  • Observational Study

MeSH terms

  • Adult
  • Birth Weight*
  • Female
  • Gestational Age*
  • Gravidity
  • Humans
  • Infant, Newborn
  • Infant, Small for Gestational Age / blood*
  • Logistic Models
  • Odds Ratio
  • Pregnancy
  • Pregnancy Trimester, First / blood*
  • Pregnancy-Associated Plasma Protein-A / analysis*
  • Prenatal Diagnosis / methods*
  • Retrospective Studies
  • Risk Assessment / methods
  • Risk Factors


  • Pregnancy-Associated Plasma Protein-A