These days women have a new choice when it comes to birth control: their smartphones.
Using a fertility-tracking app like Kindara can help a couple get pregnant or avoid pregnancy. Kindara has helped more than 30,000 women get pregnant so far. CEO William Sacks says the company recently got curious about the thing that makes them pregnant: sex.
So he and his team analysed 1.5 million bits of data that app users collected about their sexual activity over the last 22 months and discovered some surprising insights.
Here's the chart that shows a big spike in frequency over the winter holidays, relative to the number of people using the app.
The least favourite time for most women is the day before her period starts as well as the first day of it.
Here's the chart showing when women are up for sex based on their monthly cycles. Day 0 is the start of her period.
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