Low-dose aspirin for pre-eclampsia prevention is most effective when started at which gestational age, based on current evidence including the ASPRE trial?

• A Before 8 weeks gestation
• B Between 16 and 20 weeks gestation
• C Between 11 and 14 weeks gestation ✓
• D At 24 weeks gestation

Explanation

The ASPRE trial (2017) demonstrated that aspirin 150 mg/day initiated between 11–14 weeks (first trimester screening visit) in high-risk women selected by the FMF combined screening algorithm reduced preterm pre-eclampsia by ~62%. Starting before 16 weeks, particularly at 11–14 weeks, is the critical window; later initiation is significantly less effective. The mechanism involves early trophoblast invasion modulation.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.