The study examined the relationship between subchorionic hematoma (bleeding under the amniotic membrane) and miscarriages in women after artificial insemination. The research included 275 patients with a subchorionic hematoma and 336 without it between February 2017 and November 2022. Women with a subchorionic hematoma had a significantly higher rate of spontaneous abortion - 13.5% compared to 8.3% in women without a hematoma. Three common factors were found among the patients who miscarried: more embryos were transferred, the hematoma was detected earlier, and the gestational sac was smaller. The most important finding is that the risk of miscarriage increased gradually with the increasing proportion of hematoma in the gestational sac. The researchers concluded that the proportion of subchorionic hematoma in the gestational sac is a statistically significant risk factor for miscarriage in patients after artificial insemination.