Luteinizing hormone activity in ovarian stimulation: comparative efficacy and safety of gonadotropins versus recombinant follicle-stimulating hormone—a systematic review and meta-analysis

Background: recombinant follicle-stimulating hormone (rFSH) for controlled ovarian stimulation (COS). Methods: . We searched the MEDLINE, Embase, and CENTRAL databases. We calculated the mean differences (MDs) and risk ratios (RRs) for continuous and dichotomous outcomes, respectively. Results: = 17.1%; 19 studies, moderate certainty of evidence). Subgroup analysis by downregulation protocol, ovarian reserve, and age showed some differences in the effects between the compared groups. Conclusions: The evidence of gonadotropins with LH activity (±rFSH) when compared with rFSH alone probably results in little to no difference in live birth and ongoing pregnancy. However, there is a slight reduction in the number of oocytes retrieved. Moreover, they are safer than rFSH alone because they probably do not increase OHSS. Therefore, based on our review, the benefit-risk balance favors the addition of an LH-active gonadotropin for the prevention of OHSS. More studies are needed to determine the effects in specific populations. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD42024572731, identifier CRD42024572731.