Outcomes of pregnancies diagnosed with circumvallate placenta, and use of uterine artery pulsatility index and maternal serum alpha-fetoprotein for prediction of adverse outcomes.

OBJECTIVES

To evaluate the outcomes, and predictive value of uterine artery pulsatility index (UtA-PI) and second-trimester maternal serum alpha-fetoprotein (MSAFP) for adverse obstetric outcomes in cases with morphologically confirmed circumvallate placenta by comparison with normal pregnancies.

STUDY

DESIGN

This prospective study was conducted in a tertiary referral hospital between January 2017 and December 2019. During the study period, 77 patients with a circumvallate placenta and 77 patients without any placental or feto-maternal diseases or abnormalities were evaluated. The final diagnosis was made based on macroscopic examination of the placenta soon after birth. Demographic characteristics, MSAFP, obstetric complications, haemoglobin after delivery, gestational week of birth, fetal sex, 1- and 5-min Apgar scores, postnatal complications and type of delivery were retrieved from hospital records. Bilateral mean transabdominal UtA-PI and MSAFP were evaluated for the prediction of adverse outcomes. SPSS Version 21.0 for Windows was used for statistical analysis, and receiver operating characteristic (ROC) curves were used for the prediction model of adverse outcomes.

RESULTS

Smoking rate, MSAFP, preterm birth and intrauterine growth restriction (IUGR) were higher in the patients with a circumvallate placenta (p = 0.005, 0.00, 0.025 and 0.027, respectively). The cut-off value of MSAFP was 1.41 (0.60-3.32) and the cut-off value of UtA-PI was 1.2 using the ROC curves, and had sensitivity of 73.7 % and specificity of 71.9 %, and sensitivity of 73.7 % and specificity of 76.3 %, respectively (p < 0.05).

CONCLUSIONS

Circumvallate placenta was associated with a higher rate of IUGR, preterm birth and bleeding at the time of delivery. In patients with a circumvallate placenta, UtA-PI and MSAFP may be valuable as predictors of IUGR.