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You're ready to get pregnant, and you want to know when you're most likely to conceive. That means figuring out when you're ovulating. You can try to pick out your most fertile days on your own, but there are tests and kits that can give you a clearer idea of the best time for baby-making.

First, review the basics:

  • You can ovulate anywhere from 13 to 20 days before your next period.
  • To get pregnant, you should have sex a few days leading up to and on the day of ovulation.
  • Sperm can live up to 6 days in your body, but your egg can only survive 12 to 24 hours. That's why having sex before and during ovulation is best, so that you raise the odds of the sperm and egg meeting.
  • You can use basal body temperature (BBT) charting to figure out if you’ve ovulated, but it's not foolproof.

Ovulation Predictor Kits (OPKs)

Ovulation predictor kits help you find the days when you’re most fertile. But many couples can conceive on their own without using them.

"I don't typically recommend this right off the bat," says Caren Schaecher, MD, an OB/GYN at Women's Health Care at St. Luke's Hospital in Chesterfield, Mo.

But if you’ve been trying for a few months with no luck, it may help you to know your most fertile times, and these kits can help, she says.

They might also help couples who have timing issues. For instance, if you or your partner travels a lot for work, you can plan ahead.

They can also ease stress for couples who are feeling pressured about trying to get pregnant.

"The rest of the month they can feel like they're just a normal couple, and they're not hyper-focused on fertility," says William B. Schoolcraft, MD, founder and medical director of the Colorado Center for Reproductive Medicine.

Ovulation Predictor Kits: Urine

Ovulation predictor kits test your urine for levels of the hormone that triggers ovulation, called luteinizing hormone (LH). "The LH surge is typically 24 to 36 hours before ovulation," Schaecher says.