Women's Health
How long is pregnancy?
Estimated wait
~9 months
Based on published sources
The due date is only an estimate — only about 4–5% of babies are actually born on it, though roughly 90% arrive within two weeks either side. General information, not medical advice.
A human pregnancy lasts about 40 weeks (280 days) counted from the first day of your last menstrual period — roughly 9 months, or about 38 weeks (266 days) from conception. Most births happen within the 37–42 week window, with 39–40 weeks considered full term.
More details
Dates are measured from the last period because that is the standard clinical dating, refined by the early-pregnancy ultrasound around the 12-week scan.
Last updated: 10 Jul 2026
Information is for general knowledge only.