Definition:
Your fertile window refers to the time period where sex may lead to pregnancy. Since sperm can live up to six days inside the woman's reproductive track, your fertile window is technically up to six days before you ovulate. Sex, however, is more likely to result in pregnancy if it happens within the two to four days before ovulation. Sex during this time period is the most likely you'll pregnant.
Learn more about ovulation and your fertile window in these articles:
