The Most Popular Times To Have Sex And Other Fun Facts About Making Whoopee

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.

The weeks around Christmas and the New Year are by far the most popular time of year to have sex...

... and then New Year's Day. Not everyone wakes up with a hangover.

Officials celebrate the successful 2014 New Year's Eve Confetti Test at Hard Rock Cafe in Times Square

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 most popular day for sex is Sunday.

A Sunday on La Grande Jatte -- 1884

Tuesday is the least sexy day of the week. More people prefer Monday over Tuesday.

Here's the chart showing just how popular Sunday is for sex compared to the other days.

Women are most into sex on 'Day 6' of their fertility cycle.

And really, that whole first week is a sexy time for her.

Miranda Grey, author of The Optimised Woman, calls that week 'The Dynamic Phase.'

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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