Low-dose aspirin prophylaxis for pre-eclampsia is MOST effective when initiated at:

• A Between 12–16 weeks of gestation ✓
• B Before 12 weeks of gestation
• C After 20 weeks once high-risk features are confirmed
• D At the time of booking regardless of gestation

Explanation

The landmark ASPRE trial demonstrated that aspirin 150 mg at night, commenced between 11+0 and 13+6 weeks and continued until 36 weeks, reduced preterm pre-eclampsia by 62% in high-risk women identified by first-trimester screening. Benefits are substantially reduced when aspirin is started after 16 weeks because placentation is largely complete by that time. Starting before 12 weeks has no additional benefit over the 12–16 week window.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.