How do i increase my fertility window?

Fertility "window": Get an ovulation kit at a drugstore, and start testing at about day 12 (if your cycle is 28-32 days). Once you are familiar with when you ovulate based on that test, you should tell your partner to abstain for a week prior to ovulation, and have sex every other day . Eggs can be fertilized for about four days, and sperm lives for the same length of time, so pregnancy is possible for about a week.