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Some Fertility Apps May be Wrong

July 26, 2016

The key to getting pregnant is to know when you ovulate, and more women are turning to technology for the answer.

Unfortunately, it may not always work. A new study indicates that many fertility apps aren’t able to correctly pinpoint when a woman is most fertile.

Researchers from New York-Presbyterian Hospital/Weill Cornell Medical College tested 53 fertility calculators — 20 websites and 33 apps. They put the same information into all the calculators, including a 28-day menstrual cycle and the same date of the last period for a hypothetical woman. Researchers found that only four of the calculators (one website and three apps) correctly predicted the most fertile days — a 75 percent failure rate. The standout fertility calculators included, Period Tracker and the apps Clue and My Days - Period & Ovulation.

For most women, the optimal time to get pregnant is the day they ovulate and the five days afterward. On a 28-day menstrual cycle, a woman’s fertile window would be between days 10 through 15, meaning most women only have six days out of the month where the stars align to reproduce. However, many of the inaccurate calculators indicated a 10-day fertile window, along with incorrectly guessing when a woman ovulated.

Researchers say the calculators could hinder a woman’s chances to get pregnant, especially if she already is dealing with fertility issues. On the other hand, other couples may use fertility apps to avoid pregnancy. If most of these apps are inaccurate, it could put these couples in the position of an unintentional pregnancy.

Women who are trying — or not trying — to get pregnant should instead use tried-and-true methods. Keep a menstrual calendar to track your periods, pay attention to your body and watch out for signs that include pain in your abdominal area leading up to your period. For several months, chart your basal body temperature (BBT) to gauge your fertile window.  BBT changes throughout your cycle as your hormones change. It will be lowest when you ovulate and steadily increase about a half a degree right after ovulation. Also pay attention to changes in your vaginal mucus. Around ovulation, this mucus will resemble the consistency and appearance of an egg white. I know it’s not the most pleasant way to determine ovulation, but it’s effective. The body and science has a way of providing clarity in a way that technology sometimes can’t.

Another option? Try an ovulation predictor kit, which can tell you when you’re ovulating within a 24 to 36-hour timeframe. When used correctly, these tests are 99 percent accurate.

All these methods can increase your chances of fertility. However, it’s important also to seek advice from a doctor who can provide you with more information and medical advice that you just can’t get from an app.