The effect of first trimester subchorionic hematoma on pregnancy outcomes in patients underwent IVF/ICSI treatment

The aim of this retrospective cohort study was to assess the effect of subchorionic hematoma (SCH) on pregnancy outcomes in IVF/ICSI patients.We retrospectively analyzed 1097 pregnancies achieved by in vitro fertilization and embryo transfer (IVF-ET) or frozen-thawed embryo transfers (FETs) between January 2013 and June 2013 at the IVF center of Nanjing Drum Tower Hospital. The prevalence of SCH was 12.1% in this group (133/1097). We compared the pregnancy outcomes between the SCH group and non-SCH group, while the risk factors for SCH were also evaluated.There was no significant difference between SCH group and non-SCH group with regard to patients' age, spouse's age, endometrial thickness, miscarriage rate (5.6% versus 6.2%, p > 0.05), second trimester fetus loss rate (5.6% versus 7.7%, p > 0.05) or live birth rate (89.5% versus 86.1%, p > 0.05). While the birth weight in singleton pregnancy in SCH group was significant lower (3207.8 ± 595.7 g versus 3349.2 ± 59.7 g, p = 0.03). SCH was more common in fresh embryo transfer patients than that in FET patients (16.6% versus 5.1%, p < 0.01), fresh embryo transfer was a high risk for SCH with OR 3.67, 95% CI: 2.28-5.90.We concluded that SCH was associated with lower birth weight in singleton pregnancy, but SCH did not increase pregnancy loss rate in IVF/ICSI patients, and fresh embryo transfer may contribute to SCH onset.