Research

Hormonal

Weight gain of 15 kg or more since age 17 is associated with reduced fecundability (longer time-to-pregnancy), independent of current BMI at age 17.

If you have gained 15 kg or more since your late teens, your ability to conceive may be reduced, even if your current weight is within a 'normal' range. This suggests that the process of weight gain itself, or the metabolic changes it brings, can impact fertility.

GoodSupportsHIGH confidence
Compared with women who maintained a stable weight since age 17 (25 to 4 kg), women who gained >=15 kg had longer TTPs (FR = 0.72, 95% CI = 0.59 –0.88) after adjustment for BMI at age 17.
Lauren A. Wise et al. · Human Reproduction · 2009

Why this rating

Prospective cohort design allows for temporal assessment of weight change, strengthening causal inference.

Source

An internet-based prospective study of body size and time-to-pregnancy

Lauren A. Wise et al. · Human Reproduction · 2009

DOI 10.1093/humrep/dep360

cohort · n=1651Cited 265×
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DOI resolved against Crossref · corpus check 2026-06-10

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