Research

Hormonal

Obesity (BMI ≥30 kg/m²) significantly impairs female fecundity and increases the risk of miscarriage through hormonal perturbations (elevated leptin, insulin resistance, altered SHBG) and direct effects on oocyte quality and endometrial receptivity.

If you have a BMI over 30, your risk of infertility and miscarriage is significantly higher due to hormonal imbalances like high leptin and insulin resistance. However, this is not permanent. Losing weight, even modestly (5% or more), can restore normal ovulation and significantly improve your chances of conceiving naturally or through assisted reproduction. Consult a specialist for a weight management plan tailored to fertility.

GoodSupportsHIGH confidence
Obese women are three times more likely to suffer infertility than women with a normal body mass index (BMI; Rich-Edwards et al. 1994)... Obesity impairs ovulation but has also been observed to detrimentally affect endometrial development and implantation.
Christopher Brewer et al. · Reproduction · 2010

Why this rating

The paper cites multiple large population studies, meta-analyses, and retrospective analyses, though it notes some heterogeneity in study designs regarding oocyte quality.

Source

The adverse effects of obesity on conception and implantation

Christopher Brewer et al. · Reproduction · 2010

DOI 10.1530/rep-09-0568

narrative_reviewCited 492×
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DOI resolved against Crossref · corpus check 2026-06-10

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