Recurrent pregnancy loss and inherited thrombophilias: Does low molecular weight heparin improve the live birth rate?

Quenby S, Booth K, Hiller L, et al; ALIFE2 Block Writing Committee and ALIFE2 Investigators. Heparin for women with recurrent miscarriage and inherited thrombophilia (ALIFE2): an international open-label, randomised controlled trial. Lancet. 2023;402:54-61. doi:10.1016/S0140-6736(23)00693-1.

EXPERT COMMENTARY

“Follow the evidence to where it leads, even if the conclusion is uncomfortable.”

—Steven James, author

Women with RPL have endured overzealous evaluations and management despite a lack of proven efficacy. From alloimmune testing that results in paternal leukocyte immunization¹ and the long-entrusted metroplasty for a septate uterus recently put under fire² to the “hammer and nail” approach of preimplantation genetic testing for embryo aneuploid screening,³ patients have been subjected to unsubstantiated treatments.

While the evaluation of RPL has evolved, guidelines from the American Society for Reproductive Medicine (ASRM), American College of Obstetricians and Gynecologists (ACOG), and Royal College of Obstetricians and Gynaecologists (RCOG) do not recommend testing for inherited thrombophilias outside of a history for venous thromboembolism.^4-6 These 3 societies support treating acquired thrombophilias that represent the antiphospholipid antibody syndrome.

Citing insufficient evidence for reducing adverse pregnancy outcomes, ACOG recommends the use of prophylactic- or intermediate-dose LMWH or unfractionated heparin (UFH) for patients with “high-risk” thrombophilias only to prevent venous thromboembolism during pregnancy and continuing postpartum.⁴ (High-risk thrombophilias are defined as factor V Leiden homozygosity, prothrombin gene G20210A mutation homozygosity, heterozygosity for both factor V Leiden homozygosity and prothrombin gene G20210A mutation, or an antithrombin deficiency.⁴)

To determine the impact of LMWH treatment versus no treatment on live birth rate, Quenby and colleagues conducted a prospective randomized controlled trial of women with RPL and inherited thrombophilias (the ALIFE2 trial). This was a follow-up to their 2010 randomized controlled trial that demonstrated no effect of LMWH with low-dose aspirin versus low-dose aspirin alone compared with placebo in women with unexplained RPL.⁷

^{PHOTO: BETAVERSO/SHUTTERSTOCK}

Continue to: Details of the study...