Open Splash

Ovulation

About 12 to 16 days before the next period.

What happens in the ovulation?

When oestrogen gets high enough, the brain releases a big burst of LH. Ovulation follows within about 36 hours. The egg lives for roughly 12 to 24 hours. Sperm can survive for several days, which is why the fertile window starts before ovulation. The NHS says ovulation happens roughly 10 to 16 days before your next period.

What people tend to notice, and what helps

Read more about this phase

Sources

  1. NHS: Periods and fertility in the menstrual cycle
  2. Cleveland Clinic: Menstrual cycle
  3. Cleveland Clinic: Ovulation
  4. Bull et al. (2019) Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles, npj Digital Medicine

This is general information, not medical advice. Splash can’t diagnose. If you’re worried, talk to a GP, pharmacist or sexual health clinic. In an emergency call 999 (UK) or 911 (US).

Know which phase you are in today.

Splash shows your phase on the cycle ring every morning, with tips that fit it. Free, no account.