How long have I been pregnant for?

You’ll be asked again and again for the date of your last period, ie the first day of your last cycle. This will help to pinpoint the beginning of your pregnancy, but it isn’t totally accurate: you can have a cycle with periods but without ovulation, and also the time of ovulation can vary. So don’t just take the 14 days after the start of your period as your most fertile time! Couples who are trying for a baby shouldn’t just limit their baby-making to the usual time of ovulation (between the 10th and 17th day of the woman’s menstrual cycle).