You’re Most Likely Having Sex On The Wrong Day Of Your Cycle: Technology and Inaccurate “F

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Our mission at Aphrodite is to pull women out of the darkness of infertility and to get them to the family they've always wanted. We are totally into educating our patients so that they can make the most informed decisions about their reproductive health.

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You’re Most Likely Having Sex On The Wrong Day Of Your Cycle: Technology and Inaccurate “F

Let me guess, you have an ovulation predictor app on your phone, don’t you? I mean, duh!, why not? If you call yourself a tech-savvy-lady of 2018, you’re surely taking advantage of the ez-one-click-period-tracking provided by Kindara, Period Tracker or Flo.

And while its nice to think that an algorithm created by app engineers sitting in silicon valley would take your personal production of hormones and cyclical timing into account, to base your ovulation window on the “fertile days” predicted by an app will most likely result in next month’s BFN.

But Why?, you may ask…

Apps base ovulation on the rule that: ovulation occurs on average (key word!), 14 days before the start of your NEXT period. And all apps start by basing the reproductive cycle around 28 days, making for a nice round cycle, split down the middle. (28 day cycle – 14 days = Day 14 ovulation).

Like a good little average person you get a notification that “day 14 is a fertile day!” Woot woot! You jump into bed with your man and get to baby making!

But in fact you are not an average woman. Nor is this month the same as last. You may have had a stressor at work, or a night of partying that left your sleep cycle out of wack. In fact, you, and each day of this month, like others, are as unique as they come! And this month you find that your period came 25 days after your last, in which case you would have missed your fertile day on day 11. And the month before you went on vacation and your period didn’t come for 30 days, in which case your fertile day was on day 16.

Or you’ve been on the pill for the past 15 years and think your cycle is “by the book.” You don’t realize that when you stop daily doses of perfectly portioned hormones the body will have to learn to regulate itself again, which may take months to achieve. Ovulation may happen on day 9 one month, or day 19 the next, all the while your app is pushing for some Barry Manillowing on day 14.

The thing about fertility apps is that they can only predict ovulation based on looking at last month’s data retroactively. That doesn’t make for much accuracy.

Don’t get me wrong though, apps like Kindara, Period Tracker, and Flo are great tools to input daily reproductive markers like basal body temperature, menstruation characteristics and days of intercourse. But if you are searching for the most accurate time to have sex in order to achieve pregnancy, the clearest sign of ovulation comes from cervical secretions. Unlike ovulation predictions based on the calendar, your cervical secretions change the actual day before you ovulate, signaling the truest “fertile day.”

To learn more about how to track your cervical mucus (its not hard, I promise!) see my past post : Cervical Secretions: The Most Important Predictor of Ovulation.

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Hi, We're
Ghoncheh & Emily!

And we make up the team at Aphrodite Fertility Acupuncture, here in San Diego, California.

We're here to be your number one cheerleaders, your expert ttc advocates, your mystical acupuncturist gurus, and your sarcastic besties that make you laugh even in the heaviest of times.

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