How does age affect fertility?

Bottom lineFemale fertility declines gradually from about 32 and more steeply after 37 as egg quantity and quality fall (egg count drops from 300,000 to 500,000 at puberty to about 25,000 by 37), lengthening time to conceive and raising miscarriage risk; conceiving after 35 is still common, but the timing to seek help shifts earlier, so at 36 or older get assessed sooner rather than waiting a year.

Age is one of the biggest factors in fertility. Female fertility declines gradually from around 32 and more steeply after 37, driven by falling egg quantity and quality.

What changes with age

• Egg count drops over time: from about 300,000 to 500,000 at puberty, to roughly 25,000 by 37, and around 1,000 by 51 (the average menopause age)
• Egg quality declines, raising the chance of chromosomal issues
• Time to conceive lengthens, and the miscarriage rate rises

The key ages

• Under 32: fertility is relatively stable
• 32 to 37: a gradual decline begins
• After 37: a steeper decline
• Male fertility also declines with age, though more slowly

What this means

It doesn't mean conceiving after 35 is rare - it's very common. It means the timing of when to seek help shifts earlier: at 36 or older, get assessed sooner rather than waiting a full year.

What you can do

• Track your cycle to time conception well
• Consider counseling or fertility preservation (like egg freezing) if delaying
• Optimize health: folic acid, healthy weight, not smoking

Read our 2026 fertility guide and at-home hormone tests on AMH and ovarian reserve.

Femora helps you track and time cycles, which matters more as the fertile window becomes precious with age.