Antenatal findings and early postnatal outcomes in pregnancies with trisomy 21: a 10 year retrospective review at a tertiary centre.

Objective: To examine the antenatal imaging features, intrapartum findings and early postpartum course of pregnancies with trisomy 21 (T21) at a tertiary hospital in the United Kingdom.

Methods: Women with pregnancies diagnosed with T21 on antenatal or post-mortem/postnatal karyotyping, from February 2010-2020. Outcome measures included antenatal imaging findings, fetal growth restriction (FGR), birthweight, mode of delivery and early neonatal outcomes.

Results: 76 women were included. There were six intrauterine deaths and 70 livebirths. Thirty-eight (50%) had an antenatal diagnosis and twenty-five (33%) had a suspected diagnosis but declined further testing. The diagnosis was unanticipated in 13 (17%). Cardiac anomalies (35.5%) were the most common antenatal anomaly. Doppler abnormalities were apparent in 48/73 (68%). Eighteen (25.7%) had antenatal FGR. The majority were delivered by Caesarean section, and 21.4% of babies weighed
Conclusions: T21 fetuses have high rates of placental insufficiency, FGR and Doppler abnormalities. Postnatally, most require respiratory and feeding support. Antenatal counselling should reflect these risks.