The "Fifty Shades of Grey" erotic trilogy has managed to rope up more than just unprecedented sales success — now some suspect it is contributing to a baby boom as well, according to a report by Good Morning America.

Selling 20 million copies in the last four months alone, “Fifty Shades of Grey,” “Fifty Shades Darker,” and “Fifty Shades Freed” chronicle the relationship between Christian Grey and Anastasia Steele and their sadomasochistic sex life. The series, by British writer E.L. James, has been dubbed "mommy porn" and has even prompted one British hotel to replace all the bibles in its 40 rooms with the book.

The Star-Ledger reported in June that the adult books were whipping up business for adult shops across New Jersey. And it seems that 'business' has translated into babies.

Experts told Good Morning America the books are acting as an aphrodisiac of sorts, and in so doing there’s a natural course of action. Couples are getting more aroused from the trilogy, thereby having more sex, and in many cases getting pregnant as a result.

Couples struggling to get pregnant are also reportedly crediting the books with bringing the sexy back into their bedrooms.

While it may take some time to prove this theory – nine months at least – the books’ success and fandom continues to rise.

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