Step 2 of 6 · Finding your fertile window
Step 2: Try
You can get pregnant on about six days of each cycle. Here is how to find them, and how the main trackers and tests work.
The fertile window is the six days ending on ovulation day, and the two days before ovulation give the best odds. Have sex every one to two days in that window. LH strips or a fertility monitor tell you when it opens; temperature confirms ovulation afterwards.
Timing
Ovulation
Can You Only Get Pregnant During Ovulation?
No: you can get pregnant from sex up to 5 days before ovulation. See the odds by day, and whether sex on or near your period can lead to pregnancy.
Cervical Mucus: How It Changes Around Ovulation
How cervical mucus changes around ovulation, what egg-white mucus means, how to check it, and what studies show about the Billings and Creighton methods.
Does Ovulation Cause Cramps?
Yes: mid-cycle cramps called mittelschmerz affect about 1 in 5 or more. How long ovulation pain lasts, what causes it, and when cramps need a doctor.
Your Fertile Window: Which Days You Can Get Pregnant
Your fertile window is the 6 days ending on ovulation. See how many days after your period you ovulate, why it shifts, and how to track it.
Signs of Ovulation: What Your Body Shows, and How Reliable It Is
The signs of ovulation, from egg-white mucus and an LH surge to a temperature rise and mid-cycle pain, with how well each one pinpoints the day.
What Is the Luteal Phase?
The luteal phase runs from ovulation to your period, usually 11–17 days. How to measure it, what BBT does after ovulation, and what ASRM says about short phases.
Ovulation tests
How Long After an LH Surge Do You Ovulate?
Ovulation usually follows the start of the LH surge by about 32 hours, and a positive test by a day or so. Plus how long an LH surge lasts and when to have sex.
How to Read an Ovulation Test (and What a Positive Looks Like)
How to read an ovulation test: what a positive looks like, why a faint line is negative, reading times, digital and app results, and multiple positives.
When to Take an Ovulation Test: Which Day, What Time, How Often
When to take an ovulation test: the cycle day to start, the best time of day, how long the LH surge lasts, and why you can ovulate without a positive test.
Tools
Calculators for this step
The fertile window, in one paragraph
In the landmark study of 221 women trying to conceive, every pregnancy came from sex in a six-day window ending on the day of ovulation, and the odds were highest in the two days before it.1 ASRM uses the same six-day window when counseling couples and notes that sex every one to two days in that window gives the best chance, while daily sex is not necessary.2
How to find it
- Calendar. Free and quick, but only an estimate: the ovulation calculator is a starting point, not a confirmation.
- LH strips. Detect the luteinizing-hormone surge that comes one to two days before ovulation. The cheapest reliable method: see how to read an ovulation test and when to take an ovulation test.
- Fertility monitors. Measure more than LH (estrogen to open the window earlier, progesterone to confirm ovulation). They cost more per cycle than strips but show more of the cycle.
- Temperature. A rise after ovulation confirms it happened. See signs of ovulation.
- Body signs. Cervical mucus and other signs of ovulation are free and useful alongside a test.
PCOS or irregular cycles?
LH can stay high or surge more than once with PCOS, which confuses simple strips. Products that also track estrogen and progesterone, or temperature, are a better fit: see PCOS and getting pregnant and irregular periods.
This page is educational and is not medical advice. Talk to a clinician about your own situation, and seek urgent care for heavy bleeding, severe pain or fainting.
Sources
- 1Timing of sexual intercourse in relation to ovulation. New England Journal of Medicine. Wilcox AJ, Weinberg CR, Baird DD, 1995. 221 women trying to conceive
- 2Optimizing natural fertility: a committee opinion. American Society for Reproductive Medicine. Practice Committee, Fertil Steril 2022;117:53–63