The effect of subchorionic hematoma on pregnancy outcomes in cases of threatened abortion

INTRODUCTION: This study aims to compare the effects of sonographically detected subchorionic hematoma (SCH) on pregnancy outcomes in pregnant women diagnosed with threatened abortion during the first and second trimesters.
METHODS: This retrospective cohort included 446 women with threatened abortion between September 2010 and May 2015. Patients were grouped according to the presence of subchorionic hematoma on ultrasonography, and demographic, obstetric, and outcome data were retrieved from medical records. Analyses were conducted using SPSS, with independent samples t-tests for normally distributed variables and Mann–Whitney U tests for non-normally distributed variables.

RESULTS: Among the 446 women included, 136 (30.5%) had SCH. Mean age was higher in the SCH group than in those without SCH (28.30±5.23 vs. 26.82±5.5 years), whereas body mass index, gestational age at presentation, employment, smoking status, and previous mode of delivery were comparable between groups. The abortion rate did not differ significantly (44.1% vs. 40.3%, p=0.454). Notably, pregnancies complicated by SCH had a longer mean gestational duration (272.33±12.42 vs. 265.19±17.67 days, p=0.002). Although preterm birth and preterm premature rupture of membranes were the most common adverse outcomes, SCH was not significantly associated with the composite adverse obstetric endpoint (p=0.677).
DISCUSSION AND CONCLUSION: In women with threatened abortion, advancing maternal age was associated with a higher risk of SCH, and gestational duration was longer in pregnancies with SCH. However, the presence of SCH was not associated with an increased risk of adverse obstetric outcomes.

Keywords: Threatened abortion, subchorionic hematoma, adverse obstetric outcomes.