what is actually proven about the female body after forty

Weight loss and GLP-1

Weight-Lowering Drugs and Natural Female Fertility-A Systematic Review and Meta-Analysis.

5 Repeated evidence

How much this weighs: several studies in people, combined — the strongest kind of evidence there is.
Type of study
meta-analysis or systematic review
Studied in
people
Participants
575
Published
2026 in Clinical obesity
Cited
0 times by other research
Who paid
Not declared. PubMed carries no conflict-of-interest statement for most articles; that is not the same as independent.
Source
PubMed 42307450 · doi 10.1111/cob.70092
The plain-language write-up of this study is still being written. Below is the abstract exactly as the researchers published it.
Abstract by the researchers — original text

Overweight and obesity are global health concerns linked to impaired female fertility. Weight-lowering drugs are an alternative for achieving weight loss; however, their effect on natural female fertility is unclear. A systematic review and meta-analysis were conducted to summarise the literature on the effects of weight-lowering drugs on ovulation, conception, pregnancy and live birth rates. Inclusion criteria comprised interventional and observational studies involving women with overweight or obesity receiving weight-lowering drugs, compared with non-users, lifestyle modifications or other medications. MEDLINE, Embase, CINAHL, CENTRAL and ClinicalTrials.gov were searched, yielding 2731 records. After screening, seven clinical trials were included (n = 575), six of which were randomised. Sample sizes ranged from 40 to 120 women aged 25.9-29.7 years. Six trials evaluated orlistat, while one assessed semaglutide. In four trials, orlistat was associated with a higher ovulation rate than lifestyle modifications. A meta-analysis of ovulation rates comparing orlistat and metformin showed no significant difference (RR = 0.78, 95% CI: 0.41-1.49; p = 0.45). Two studies reported pregnancy rates: one found a higher rate with orlistat compared to lifestyle modifications (23.3% vs. 6.7%, p = 0.044), and another showed that adding semaglutide to metformin increased the pregnancy rate compared to metformin alone (35% vs. 15%, p < 0.05). Future studies should address current limitations and evaluate the effects of newer weight-lowering drugs on natural pregnancy and live birth rates in adequately powered studies.