3 doctors weighed in:

If she starts her period on the 15th but didn't start until the 18th and only had a one day period and she is 15 weeks pregnant what day she conceived?

3 doctors weighed in
Dr. Eva Pickler
Obstetrics & Gynecology
2 doctors agree

In brief: Depends

Probable day of conception is two weeks after the first day of the last period prior to conception.
If the due date is based on an ultrasound and not last period date, you would have to count backward 38 weeks from the due date for an approximate date. If this question is due to concerns about paternity, a paternity test after the delivery would be needed to confirm father of baby.

In brief: Depends

Probable day of conception is two weeks after the first day of the last period prior to conception.
If the due date is based on an ultrasound and not last period date, you would have to count backward 38 weeks from the due date for an approximate date. If this question is due to concerns about paternity, a paternity test after the delivery would be needed to confirm father of baby.
Dr. Eva Pickler
Dr. Eva Pickler
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