Working out a conception date.
The likely day of conception from a last period or a due date, why it is a span of days and not one day, and what dates can never tell you.
By Suraj Kumar2 min read
Conception is most likely on the day of ovulation, but it can follow sex on any of the five days before.
From a period.
Ovulation is usually about 14 days before the next period, so for a 28-day cycle it is about day 14 and for a 32-day cycle about day 18.
From a due date.
A due date is 266 days after conception, so the page counts back 266 days.
A span of days.
Sperm can live up to five days, so conception can have been on any of about six days, and cycles vary. Dates can never show who the father is; only a DNA test can.
Further reading
Topics: conception calculator · when did i conceive · conception date from due date · date of conception · ovulation day
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