Activity Restrictions for Subchorionic Hematoma in Pregnancy
For pregnant individuals with subchorionic hematoma, bed rest at home until vaginal bleeding resolves is recommended, as this approach is associated with significantly fewer spontaneous abortions (9.9% vs 23.3%) and higher rates of term pregnancy (89% vs 70%) compared to continuing usual activities.
Evidence-Based Recommendation
The strongest evidence comes from a study of 230 pregnant women with sonographically confirmed subchorionic hematoma and live embryo/fetus, where those who adhered to bed rest had markedly better outcomes than those who continued their usual lifestyle 1. While this was not a randomized trial, the magnitude of benefit (more than 50% reduction in pregnancy loss) supports this conservative approach in real-world practice 1.
Immediate Activity Modifications
Stop all moderate-to-vigorous physical activity immediately upon diagnosis of subchorionic hematoma, particularly if accompanied by vaginal bleeding 2. The Canadian Guidelines for Physical Activity throughout Pregnancy specifically list vaginal bleeding as a reason to stop physical activity and consult a healthcare provider 2.
Specific Activities to Avoid:
- High-risk activities with fall potential: horseback riding, downhill skiing, ice hockey, gymnastics, non-stationary cycling 2
- Contact sports of any kind 2
- Activities causing physical strain that could increase intra-abdominal pressure 2
- Exercise in excessive heat or humidity to prevent maternal hyperthermia 2, 3
Risk Stratification by Hematoma Size
The size of the subchorionic hematoma significantly impacts pregnancy outcomes and should guide the intensity of activity restriction:
- Large hematomas are associated with significantly higher rates of first trimester bleeding, early pregnancy loss, intrauterine growth restriction, placental abruption, and preterm delivery 4
- Medium and large hematomas show increased risk of placental abruption and early pregnancy loss compared to controls 4
- Small hematomas still warrant precautions but may have less severe outcomes 4
Duration of Restrictions
Maintain bed rest for the entire duration of vaginal bleeding 1. Follow-up ultrasound examinations should be performed at 7-day intervals until:
- Bleeding ceases completely
- The subchorionic hematoma resolves on imaging
- Or pregnancy loss occurs 1
The average duration of bleeding in affected pregnancies is approximately 29 days (range 4-72 days), so patients should be counseled to expect potentially prolonged restrictions 1.
Warning Signs Requiring Immediate Medical Attention
Seek emergency obstetric care if experiencing:
- Regular and painful uterine contractions 2
- Persistent or heavy vaginal bleeding 2
- Persistent loss of fluid suggesting membrane rupture 2
- Severe chest pain 2
- Persistent dizziness or faintness that does not resolve with rest 2
Clinical Pitfalls to Avoid
Do not reassure patients that small hematomas are always benign. While massive hematomas clearly cause space-occupying effects and can lead to fetal demise 5, even smaller hematomas warrant close monitoring as they are associated with adverse outcomes 4. The relationship between hematoma size and pregnancy outcome is not always linear, and regular examinations are essential 5.
Do not assume that absence of bleeding means the hematoma has resolved. Serial ultrasound confirmation is necessary before liberalizing activity restrictions 1.
Long-term Monitoring Considerations
Even after resolution of bleeding and hematoma, these pregnancies remain at higher risk for:
- Preterm delivery (particularly with large hematomas) 4
- Intrauterine growth restriction requiring serial growth ultrasounds 4, 6
- Placental abruption later in pregnancy 4
- Oligohydramnios 6
Therefore, continued close obstetric surveillance throughout pregnancy is warranted even after the acute phase resolves 4.