Is it possible to have gotten pregnant a day before your fertile window has started?

[EmmR70]

Need answers! Just asking for a friend

[AnnieBrooke]

It depends on if the person knows when her "fertile window" is. Some apps give a "fertile window" that takes into account the longevity of a man's sperm in a woman's body, and some don't add that in. If she is using an app that is only concerning itself with pinpointing ovulation, then she should add 5 days at the front end. (So for example if the app says her fertile window begins on the 10th but is only telling her when she ovulated, she should be thinking of sex she had from the 5th on when trying to see when she might have gotten pregnant.) But if the app includes a 5-6 day window in front of when it thinks she ovulated, to cover the fact that sperm can live that long in a woman's reproductive tract, then it might be a little harder to get pregnant before one's "fertile window."

Frankly, however, an app does not know when a woman ovulates. All it can do is record the data of when she has periods, and extrapolate averages from that past history. It is not on a hotline to her real body. Women can ovulate early or late compared to their normal cycles. It is quite common. So the short answer is, yes, someone can get pregnant when her app says she is not in her fertile window. It happens all the time.

[EmmR70]

Is it possible to have concieved on 1/10/18 from intercourse on 1/3/18

[AnnieBrooke]

Possibly. But again, how is it known absolutely that conception was 1/10? Women don't ovulate by their body consulting their app. Their body does what it wants when it wants.