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When to Take a Pregnancy Test on a 30-Day Cycle

Cycles & ovulation. Updated . Calculated with the standard pregnancy dating method used by ACOG and the NHS.

On a 30-day cycle, the most reliable time to take a home pregnancy test is cycle day 31, the day your next period is due. Some sensitive tests may pick up a pregnancy a few days earlier, from around cycle day 26.

Cycle length30 days
Likely ovulation dayCycle day 16 (range 14–18)
Fertile windowCycle days 11–16
Most fertile daysCycle days 14–16
Next period dueCycle day 31

Why you can't test straight away

Pregnancy tests detect hCG, a hormone that only starts to be made after the embryo implants, usually 6 to 12 days after ovulation. Levels then roughly double every couple of days, so testing too early can give a negative result even if you are pregnant.

If the test is negative

If your period still hasn't arrived, test again in two to three days. If you keep getting negatives and your period is more than a week late, a doctor can check for other causes.

A 30-day cycle sits within the typical adult range of 21 to 35 days.

Pregnancy Test Date Calculator: Find the earliest and the most reliable days to take a pregnancy test.

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This article is general information, not medical advice. Talk to a doctor or midwife about your own pregnancy or fertility.