Placental Size and Uterine Artery Doppler for Prediction of Adverse Pregnancy Outcomes in Women with Low Pregnancy-Associated Plasma Protein-A

Patients with a low level of pregnancy-associated plasma protein-A (PAPP-A) experience more placental disorders in the second trimester.

We aimed to assess UtA-Doppler and placental size to predict adverse pregnancy outcomes in a woman with placental insufficiency and low PAPP-A.

Following a cross-sectional design, 83 singleton pregnant women with normal chromosomes and PAPP-A ≤ 0.5 were examined at 11 - 13 + 6 weeks of gestation. All participants with PAPP-A ≤ 0.5 were tested in the Nilo laboratory of Tehran from 2018 to 2019. The placental size and Doppler uterine artery were assessed at 18 - 20 weeks. Three cases were excluded due to abortion and aneuploidy. All participants were assigned to placenta lengths of < 10 cm and > 10 cm. All comparisons between two groups were assayed by the independent t-test, Mann-Whitney U test, χ2-test or Fisher exact test, and Logistic regression model.

Of 80 women, 48 (60%) had placenta length of < 10 cm and 32(40%) had placenta length of > 10 cm. Fourteen (17.5%) were preterm (< 32 weeks), and 36(45%) were IUGR. According to the logistic regression model, in participants with a placenta length of < 10 cm, the risk of IUGR was higher by 9-time than those with placenta length of > 10 cm (OR = 9, CI95% = 3.20 - 25.29). Also, the risk of preterm labor was 3.47 fold higher in the group with placenta length of < 10 cm, OR: 3.47;( CI95% = 1.27 - 9.44). Sensitivity of placenta length of < 10 cm for predicting IUGR was 75% (CI95% = 56.60 - 88.54).

Placental length measurement in the second trimester can help predict adverse pregnancy outcomes in pregnant women with low PAPP-A. Placenta evaluation can assist in planning future pregnancy care to detect the pathology of fetal growth restriction.