Fertilidad

Ovulation tests and temperature tracking

Revisado: 4 de octubre de 2026

Solo en inglés por ahora

Ovulation tests and temperature charts can help you find your most fertile days when trying for a baby. Here is how they work and what they cannot tell you.

How ovulation tests work

Ovulation tests check your pee for luteinising hormone (LH). A sudden rise in LH, called the LH surge, triggers ovulation. It starts about 36 hours before an egg is released. A positive test means you will probably ovulate in the next 24 to 36 hours. You are most fertile in the 2 to 3 days before ovulation and for up to about a day after it. This is a good time to have sex if you are trying for a baby.

When to start testing

Start testing about 3 to 5 days before you expect to ovulate. Ovulation usually happens 10 to 16 days before your next period, so your usual cycle length helps you choose when to begin. You can pee on the test stick or dip it in pee collected in a clean container. Do not drink a lot of fluid before testing, and follow the instructions that come with your test.

What ovulation tests cannot tell you

A positive test shows a rise in a hormone. It does not prove that an egg was released. If you skip a day of testing, you may miss the surge. Tests may also not pick up a surge if your cycles are irregular. Some hormone medicines and fertility medicines can change LH levels and the result. False positive results can happen, but they are rare.

Tracking your temperature

Your body temperature at rest (basal body temperature) rises slightly just after ovulation, usually by only about 0.2 to 0.4°C (0.4 to 0.8°F). The rise shows that ovulation has probably happened, but not exactly when. Because your most fertile days come before your temperature reaches its highest point, a chart is most useful for learning your usual pattern over several cycles.

Logging and when to get help

Ciclo lets you log ovulation test results and cervical mucus next to your periods, but it does not log temperature and cannot confirm that you have ovulated. If you have been trying for a year without getting pregnant, see a doctor or nurse. Go after 6 months if you are 35 or older, and sooner if your periods are irregular or have stopped.

This is general information. Ovulation tests and temperature charts are not contraception. If you are having trouble getting pregnant, talk to a doctor or nurse.