Evaluation of perinatal outcomes in twin pregnancies undergoing amniocentesis

INTRODUCTION: To contribute to the literature by evaluating the perinatal outcomes of twin pregnancies undergoing amniocentesis at our clinic.
METHODS: Sixty-five twin pregnancies in which amniocentesis was performed on both fetuses between January 2019 and August 2025 at the Perinatology Clinic of Ankara Bilkent City Hospital were retrospectively evaluated. Chorionicity, amniocentesis (AC) week, AC indications, karyotype analysis results, gestational age at delivery, birth weights, Apgar scores, neonatal intensive care (NICU) requirement, and procedure-related complications were recorded.
RESULTS: Sixty-five patients were included in the study. Fifty-five were MCDA (monochorionic diamniotic), and ten were DCDA (dichorionic diamniotic). The karyotype was normal in 96.9% of pregnancies; anomalies were detected in two fetuses in the DCDA group. Trisomy 21 (1.5%) was detected in a single fetus in the DCDA pregnancy, and Trisomy 13 (1.5%) was detected in a single fetus in another DCDA pregnancy, and selective termination was performed on these anomalous fetuses at the request of the family. The mean amniocentesis week was 20.6±2.6 weeks. The mean gestational age at delivery was 34.5 weeks in the DCDA group and 28.0 weeks in the MCDA group (p<0.001). First/second baby birth weights and 5-minute Apgar scores were higher in the DKDA group (p≤0.031). The need for NICU admission was 95.2% in the MCDA group and 60.0% in the DCDA group (p=0.002).
DISCUSSION AND CONCLUSION: In our study, no procedure-related complications were observed in either group. Adverse perinatal outcomes are associated with TTTS and related invasive procedures rather than amniocentesis itself, especially in MCDA twins.

Keywords: Twin pregnancy, amniocentesis, chorionicity, invasive diagnostic method