From the Research
Risks of a Large Subchorionic Hematoma (SCH) at 12 Weeks Gestation
The presence of a large subchorionic hematoma (SCH) at 12 weeks gestation has been associated with several adverse pregnancy outcomes. Some of the risks include:
- Preterm delivery: Studies have shown that large SCHs are associated with a higher risk of preterm delivery, with one study finding that 24.1% of women with a large SCH delivered preterm compared to 4.2% of women with a non-large SCH and 5.3% of women without an SCH 1, 2.
- Early pregnancy loss: Large SCHs have also been linked to an increased risk of early pregnancy loss, with one study finding that women with a large SCH were more likely to experience miscarriage than those with a non-large SCH or no SCH 1, 3.
- Intrauterine growth restriction (IUGR): Large SCHs may also increase the risk of IUGR, with one study finding that 9.72% of women with an SCH experienced IUGR compared to 0% of women without an SCH 3.
- Placental abruption: The presence of a large SCH may also increase the risk of placental abruption, with one study finding that women with a large SCH were more likely to experience placental abruption than those with a non-large SCH or no SCH 1.
- Fetal demise: In rare cases, a large SCH may cause significant space-occupying effects, affecting blood supply to the fetus and potentially leading to fetal demise 4.
Factors Influencing the Risk of Adverse Pregnancy Outcomes
Several factors may influence the risk of adverse pregnancy outcomes in women with a large SCH, including:
- Size of the hematoma: Larger hematomas are associated with a higher risk of adverse pregnancy outcomes, with one study finding that women with a medium or large SCH were more likely to experience miscarriage or preterm birth than those with a small SCH 3.
- Gestational age at diagnosis: The risk of adverse pregnancy outcomes may be higher for women diagnosed with an SCH between 12 and 20 weeks gestation, with one study finding that the rate of miscarriage increased and the live birth rate decreased significantly in this group compared to those diagnosed before 12 weeks gestation 3.
- Placental location: The location of the placenta may also influence the risk of adverse pregnancy outcomes, with one study finding that an anterior placenta was a protective factor for subchorionic hematoma 3.