From the Guidelines
The primary drugs used in the management of threatened abortion are progesterone supplements, with recommended regimens including micronized progesterone 200 mg vaginally twice daily or dydrogesterone 10 mg orally twice daily, typically continued until 12-16 weeks of gestation. These regimens are based on the understanding that progesterone is crucial for maintaining pregnancy in early gestation, supporting the uterine lining, reducing uterine contractions, and modulating the maternal immune response to the developing fetus 1.
Additional considerations in the management of threatened abortion include:
- Starting treatment as soon as threatened abortion is diagnosed
- Continuing prenatal vitamins and folic acid supplementation
- Avoiding sexual intercourse and strenuous activity during treatment
- Monitoring for signs of active bleeding or worsening symptoms
The use of progesterone supplements aims to address any potential progesterone deficiency that may be contributing to the threatened abortion. While progesterone is the mainstay, other supportive measures may include bed rest and emotional support. In cases where there's an identifiable underlying cause (e.g., thyroid dysfunction), treating that condition is also important. It's also worth noting that the management of threatened abortion should prioritize minimizing morbidity, mortality, and improving quality of life for the patient, and thus, the most recent and highest quality evidence should guide clinical decision-making 1.
In terms of specific medications, micronized progesterone and dydrogesterone are the preferred options, given their established efficacy and safety profiles in the context of threatened abortion 1. The choice between these two options may depend on patient-specific factors, such as preferences, side effect profiles, and potential interactions with other medications. Ultimately, the goal of treatment is to support the continuation of the pregnancy and minimize the risk of complications, while also prioritizing the patient's overall health and well-being.
From the Research
Medications for Threatened Abortion
The following medications are used to manage threatened abortion:
- Progesterone: This hormone is essential for maintaining early pregnancy 2, 3, 4, 5, 6
- Human chorionic gonadotropin (hCG): This hormone stimulates and optimizes hormonal production in the corpus luteum and may influence the fetoplacental unit 2
- Corticosteroids with low doses of aspirin: These medications have resulted in fetal salvage in women with antiphospholipid antibodies 2
Administration and Duration of Treatment
- Progesterone can be administered vaginally or intramuscularly 3, 4, 5, 6
- The duration of progesterone treatment is controversial, with some studies suggesting treatment until 12 weeks of pregnancy 3, 6 and others recommending treatment until 16 weeks of pregnancy 3
- The optimal dose, route, and timing of administration of progesterone supplementation are not well established 5
Efficacy of Progesterone Treatment
- Some studies have shown that progesterone treatment can reduce the risk of miscarriage and preterm birth 2, 5
- However, other studies have found no significant difference in live birth rates between women treated with progesterone and those receiving a placebo 6
- The treatment effect of progesterone in women with threatened miscarriage after previous miscarriages warrants further research 6