Low-molecular-weight heparin in the prevention of unexplained recurrent miscarriage: a systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 38898143 · doi:10.1038/s41598-024-62949-5
What was done
A systematic review and meta-analysis of registered randomized controlled trials (RCTs) evaluating the efficacy of low-molecular-weight heparin (LMWH), given alone or with low-dose aspirin from the beginning of pregnancy, in women with unexplained recurrent pregnancy loss (U-RPL). The primary outcome was live birth rate (LBR). Analyses were stratified by previous miscarriages, treatment type, control type, and country. A total of 6 studies with 1,016 patients were included.
What was found
LMWH was not associated with an increase in live birth rate in U-RPL, showing a pooled odds ratio (OR) of 1.01, with medium heterogeneity (26.42%) and no publication bias. Subgroup analyses by country, treatment type, and control type similarly showed no significant effect on live birth rate, accompanied by high heterogeneity.
Why it matters
These findings provide moderate-quality evidence against the routine empiric use of LMWH to improve live birth rates in women experiencing unexplained recurrent miscarriage.
Limits
The total sample size across all included trials was modest (1,016 patients across 6 RCTs). The abstract does not report confidence intervals or safety/adverse event outcomes, and subgroup analyses demonstrated high heterogeneity.
Cited by
- contradicts Universal prophylactic use of enoxaparin in women following a first or second miscarriage would result in 2,000 to 15,000 additional live births per year in the United States.