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Fertility · 5 min

Ovulation tests, without the spiral

LH tests catch a surge, not the egg. Peak is a maybe, not a guarantee.

What they measure

Most home ovulation tests detect a rise in luteinizing hormone (LH) that often precedes ovulation by about a day. A positive or “peak” result suggests ovulation may be near. It does not prove an egg was released.

How people use them

Start testing a few days before your estimated window, at a consistent time, and follow the kit. PCOS and some medications can create extra LH noise. If tests confuse more than they clarify, it is fine to stop and talk with a clinician.

Sources

  1. American College of Obstetricians and Gynecologists. Evaluating Infertility (FAQ136). ACOG, 2020.
  2. American College of Obstetricians and Gynecologists. Fertility Awareness-Based Methods of Family Planning (FAQ024). ACOG, 2019.
  3. Office on Women's Health (U.S. Department of Health and Human Services). Your menstrual cycle. womenshealth.gov, 2025.
  4. Bull JR, Rowland SP, Scherwitzl EB, Scherwitzl R, Gemzell Danielsson K, Harper J. Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles. npj Digital Medicine, 2019.

Educational information for general awareness. This article has not been individually reviewed by a clinician for you, and it is not medical advice.