Effect of heparin on the outcome of IVF treatment: a systematic review and meta-analysis

The effect of heparin on IVF outcome has been widely debated in the literature. A systematic review and meta-analysis of the published literature was conducted to evaluate the effect of heparin treatment on IVF outcome. Searches were conducted on MEDLINE, EMBASE, Cochrane Library and Web of Science and identified 10 relevant studies (five observational and five randomized) comprising 1217 and 732 IVF cycles, respectively. The randomized studies included small numbers of women and exhibited high methodological heterogeneity. Meta-analysis of the randomized studies showed no difference in the clinical pregnancy rate (RR 1.23, 95% CI 0.97-1.57), live birth rate (RR 1.27, 95% CI 0.89-1.81) implantation rate (RR 1.39, 95% CI 0.96-2.01) and miscarriage rate (RR 0.77, 95% CI 0.24-2.42) in women receiving heparin compared with placebo during IVF treatment. However, meta-analysis of the observational studies showed a significant increase in the clinical pregnancy rate (RR 1.83, 95% CI 1.04-3.23, P = 0.04) and live birth rate (RR 2.64, 95% CI 1.84-3.80, P < 0.0001). The role of heparin as an adjuvant therapy during IVF treatment requires further evaluation in adequately powered high-quality randomized studies. RBMOnline