Outcomes of subchorionic hematoma-affected pregnancies in the infertile population

To determine the implications of an incidentally noted subchorionic hematoma on pregnancy outcomes in the infertile population.

Retrospective cohort study at a tertiary care, university-based facility. All patients with intrauterine pregnancy on initial obstetric ultrasound presenting to an infertility clinic between January 2015 and March 2018 (n = 1210), regardless of treatment cycle, were included. Nonviable pregnancies were excluded. The main outcome measured was association between subchorionic hematoma and first trimester miscarriage.

The prevalence of subchorionic hematoma was 12.5% (n = 151) and did not differ by type of fertility treatment. There was no association between subchorionic hematoma and first trimester miscarriage; however, among patients with subchorionic hematoma, those who reported both bleeding and cramping had an increased probability of miscarriage compared to those without symptoms (0.62 vs. 0.12, P <0.001). The live birth rate in this sample was 81.3% and there were no statistically significant differences in pregnancy outcomes between those with and without subchorionic hematoma.

Among an infertile population, there was no increased risk of miscarriage when subchorionic hematoma was seen on early ultrasound; however, when patients noted both vaginal bleeding and cramping, their probability of miscarriage was significantly increased.