title: Meta-analysis of low-molecular-weight heparin to prevent recurrent placenta-mediated pregnancy complications.
abstract: A 35-year-old woman with recurrent severe placenta-mediated pregnancy complications in her 2 pregnancies asks: Will low-molecular-weight heparin help prevent recurrent placenta-mediated pregnancy complications in my next pregnancy? We performed a meta-analysis of randomized controlled trials (RCTs) comparing low-molecular-weight heparin (LMWH) vs no LMWH for the prevention of recurrent placenta-mediated pregnancy complications. We identified six RCTs that included a total of 848 pregnant women with prior placenta-mediated pregnancy complications. The primary outcome was a composite of pre-eclampsia (PE), birth of a small-for-gestational-age (SGA) newborn (<10th percentile), placental abruption, or pregnancy loss >20 weeks. Overall, 67 (18.7%) of 358 of women being given prophylactic LMWH had recurrent severe placenta-mediated pregnancy complications compared with 127 (42.9%) of 296 women with no LMWH (relative risk reduction, 0.52; 95% CI, 0.32 to 0.86; P = .01; I(2), 69%, indicating moderate heterogeneity). We identified similar relative risk reductions with LMWH for individual outcomes, including any PE, severe PE, SGA <10th percentile, SGA <5th percentile, preterm delivery <37 weeks, and preterm delivery <34 weeks with minimal heterogeneity. LMWH may be a promising therapy for recurrent, especially severe, placenta-mediated pregnancy complications, but further research is required.
authors.affiliation: Hematology.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Rodger
authors.forename: Marc
authors.initials: M
authors.lastname: Carrier
authors.forename: Grégoire
authors.initials: G
authors.lastname: Le Gal
authors.forename: Ida
authors.initials: I
authors.lastname: Martinelli
authors.forename: Annalisa
authors.initials: A
authors.lastname: Perna
authors.forename: Evelyne
authors.initials: E
authors.lastname: Rey
authors.forename: J I P
authors.initials: JI
authors.lastname: de Vries
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Gris
mesh_terms: D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage; D010922:Placenta Diseases / Q000517:prevention & control; D011225:Pre-Eclampsia / Q000517:prevention & control; D011248:Pregnancy Complications / Q000517:prevention & control; D055502:Secondary Prevention
chemical_list: D006495:Heparin, Low-Molecular-Weight