I’ve remained childless by choice, so I’ve never tried to conceive. But I’ve watched friends and family go through the process. Some create a baby the first month they try. Others struggle with infertility, which means a couple not using birth control has unsuccessfully tried to get pregnant for at least a year.

Both sexes can contribute to infertility. Underlying female reasons can include structural problems like endometriosis and pelvic adhesions or hormonal irregularities that result in ovarian dysfunction. Those stemming from the male side can include decreased sperm count or low motility. But some causes of infertility remain a mystery, says Dr. Kathleen Green, an OBGYN at the University of Florida Health Women’s Center. There are blood tests to determine ovarian function, but even if your ovaries are in tip-top shape, that won’t guarantee you’ll get pregnant. This is why Dr. Green doesn’t routinely suggest getting fertility tests done before patients have tried for a year. 

“Even if we do all of the tests and everything comes back normal, it doesn’t mean much,” says Dr. Green. “About 30 percent of the time, infertility is unexplained with normal lab results and imaging.”

It would be nice if science could help people cut to the chase and determine their chances of conceiving before they struggle for a year. But until then, decoding your menstrual cycle — whether with a regular calendar or a period-tracking app — is the best way to increase your chances of getting pregnant, says Dr. Green. Here are some of her tips to help you get the timing right.

Test for fertility in the morning
Ovulation kits work by measuring a surge of luteinizing hormone, which typically happens in the morning, says Dr. Green. This is why you’ll want to test your first pee of the day. If you have a regular 28-day cycle, you can start testing seven days after your period. If you’re like me, and you have a shorter cycle, Dr. Green says you can start testing at day five. If you know when you ovulate, it’s easier to introduce sperm at the right time.

“Your goal is to have intercourse within 24 hours of that positive test,” says Dr. Green.

Don’t have sex every day of your fertile period
Sperm can live in the body for a maximum of five days, so ideally it would be hanging around when ovulation happens. The 24-hour window Dr. Green mentioned includes the day before and the day after ovulation. But you don’t want to have sex every day in your fertile window.

We like intercourse every other day around ovulation time,” says Dr. Green. “But not every day, because that can decrease sperm count.”

So if you ovulate on day 14, plan for sex the day before. Skip the sex on ovulation day, let your partner’s sperm build up, then have sex again on day 15.

What’s the best ovulation kit?
There are a lot of different options, but Dr. Green suggests picking one that is easy to read. She recommends opting for one that shows the results with something like a plus or minus or a smile or frown. The ones that offer gradations of color are often hard to interpret, she says.

When to talk to a doctor
You’ve only got about a 20 percent chance of conceiving each month, says Dr. Green. So don’t get frustrated too quickly. But if you’ve foregone birth control and timed your sex with ovulation for a year, check in with your doctor. If you’re 35 or older, your likelihood of getting pregnant starts to decline, so you may want to get an evaluation after six months, says Dr. Green.

“Infertility is really a misnomer. I think a better way to describe it is sub-fertile,” says Dr. Green. “It’s not really infertility. It’s just that, statistically speaking, you haven’t been able to get pregnant.”

Keri Wiginton is a writer and photographer focusing on issues related to women's health, mental well-being, and feminism. Her work has appeared in the Chicago Tribune, Washington Post, Austin-American Statesman, Tampa Bay Times and Houston Chronicle. Follow her work at www.keriwiginton.com or on Twitter at @keriphoto.