From the Research
Low-dose aspirin (81-100 mg daily) for recurrent pregnancy loss should be started before 11 weeks' gestation, as early administration may reduce the risk of preterm delivery, according to the most recent and highest quality study 1.
Key Considerations
- The American journal of obstetrics and gynecology study 1 found that low-dose aspirin initiated at <11 weeks' gestation was associated with a nonsignificant reduction in the risk of preeclampsia, gestational hypertension, and any hypertensive disorder of pregnancy, but significantly reduced the risk of preterm delivery.
- The mechanism behind aspirin's benefit involves its antiplatelet effects, which improve placental blood flow and reduce inflammation by inhibiting prostaglandin synthesis, helping prevent placental thrombosis and promoting proper placental development.
- Aspirin therapy is most effective when combined with other treatments like low molecular weight heparin in cases with confirmed antiphospholipid syndrome, as shown in the meta-analysis of randomized controlled trials 2.
Important Factors to Consider
- Before starting aspirin, patients should consult with their healthcare provider to ensure there are no contraindications such as aspirin allergy, active peptic ulcer disease, or bleeding disorders.
- The medication should be continued until 36 weeks of gestation, as starting aspirin after 16 weeks significantly reduces its effectiveness in preventing complications like preeclampsia and recurrent pregnancy loss.
- A study on the treatment of recurrent spontaneous abortion in women with antiphospholipid antibody syndrome found that aspirin plus heparin or heparin alone therapy improved live birth rates, while aspirin alone did not show a statistically significant difference compared to placebo 2.