Researchers found on average women slept with their partners just once a week before reading the book, but this leapt to three times every week once they finished the erotic read.
One in eight women now bed their other half every day, up from just three percent this time last year, an online found.
And the nation’s sex sessions are lasting longer too - with men enjoying on average an extra 26 hours of sex a year.
Two-thirds of women said reading the book made their lovemaking last longer, with the average session now taking 15 minutes more, with one in 25 couples enjoying romps an extra hour long.
Couples have also been inspired to use extra sex positions after reading the sexually adventurous book.
Previously one in eight used just one position each time they made love, but now over 40 percent of couples cram in five or more positions each time they have sex.
The UK’s favourite sex position is now the “Reverse Cowgirl,” replacing the tamer “Doggy Style,” which couples favoured before finishing the steamy read.
Overall 64 percent of women said the sizzling page-turner had made them more sexually adventurous, while 54 percent said the boost to their love life had made them emotionally closer to their partner too.
The raunchy read also sparked a baby boom with one in 33 women who read it ending up pregnant and a further nine percent using the book to tempt their man into more sex in a bid to fall pregnant.
A third of girls fell pregnant in the very first month they started reading the book, with a further 42 percent pregnant the month after.
Of the 2,183 women polled by Netmums, nearly half (49 percent) said their partner was delighted they read the book as it spiced up their sex life and eight percent of men have actually read it.
Two in five women also bought sex toys or visited a sex shop after reading the book.
The most popular purchases were blindfolds, handcuffs and vibrators with half trying these - while an adventurous one in five snapped up bondage ties, sex balls, whips and paddles.
“It’s not called Mummy Porn for nothing. The book has set Britain’s sex lives on fire with even worn-out mums finding much more time to make love,” the Daily Mail quoted Netmums founder Siobhan Freegard as saying.
“It’s a phenomenon which has put a smile on millions of women’s faces - and the twinkle back in their partner’s eyes.
“But it’s also interesting to see how reading the book and spicing up your sex life can make you emotionally closer to your partner. Here’s hoping the 50 Shades effect will see couples grow stronger together and well as having more fun in the sack,” Freegard said.