Why some couples have more sex

By Drake Baer, Science of Us

Updated 9:11 AM ET, Wed May 25, 2016

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"Fifty Shades of Grey" came out around Valentine's Day in 2015, a perfect time for a film whose sex scenes had some blushing red. It isn't the first movie with risque scenes that had moviegoers titillated.
Photos: Hollywood's steamiest sex scenes
'Fifty Shades of Grey' (2015) – "Fifty Shades of Grey" came out around Valentine's Day in 2015, a perfect time for a film whose sex scenes had some blushing red. It isn't the first movie with risque scenes that had moviegoers titillated.
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Graphic sex scenes between Marlon Brando and Maria Schneider in "Last Tango in Paris" shocked the world at the time and initially earned the film <a href="http://mentalfloss.com/article/28925/what-happened-x-rating" target="_blank">an X rating as well as two Academy Award nominations. </a>
Photos: Hollywood's steamiest sex scenes
'Last Tango in Paris' (1972) – Graphic sex scenes between Marlon Brando and Maria Schneider in "Last Tango in Paris" shocked the world at the time and initially earned the film an X rating as well as two Academy Award nominations.
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The graphic sex scenes between Donald Sutherland and Julie Christie in "Don't Look Now"<a href="http://web.archive.org/web/20110810181107/http://www.film4.com/features/article/nicolas-roeg-on-dont-look-now" target="_blank"> resulted in an X rating</a> at first and have fans still wondering, did they or didn't they?
Photos: Hollywood's steamiest sex scenes
'Don't Look Now' (1973) – The graphic sex scenes between Donald Sutherland and Julie Christie in "Don't Look Now" resulted in an X rating at first and have fans still wondering, did they or didn't they?
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"Nine 1/2 Weeks," starring Mickey Rourke and Kim Basinger, wasn't a huge commercial success, and critics didn't love it -- <a href="http://www.rogerebert.com/reviews/9-12-weeks-1986" target="_blank">except maybe Roger Ebert</a> -- but it had couples acting out that <a href="http://www.youtube.com/watch?v=sIwD-oDm6cU" target="_blank">food scene.</a>
Photos: Hollywood's steamiest sex scenes
'Nine 1/2 Weeks' (1986) – "Nine 1/2 Weeks," starring Mickey Rourke and Kim Basinger, wasn't a huge commercial success, and critics didn't love it -- except maybe Roger Ebert -- but it had couples acting out that food scene.
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Daniel Day-Lewis and Lena Olin had some sexy scenes in "The Unbearable Lightness of Being."
Photos: Hollywood's steamiest sex scenes
'The Unbearable Lightness of Being' (1988) – Daniel Day-Lewis and Lena Olin had some sexy scenes in "The Unbearable Lightness of Being."
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<a href="http://www.toobeautiful.org/lat0429.html" target="_blank">Gay activists protested "Basic Instinct</a>," starring Michael Douglas and Sharon Stone, as they felt that the portrayal of her bisexual character was offensive.
Photos: Hollywood's steamiest sex scenes
'Basic Instinct' (1992) – Gay activists protested "Basic Instinct," starring Michael Douglas and Sharon Stone, as they felt that the portrayal of her bisexual character was offensive.
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Jane March and Tony Leung Ka Fai star as a young girl and her older lover in "The Lover."
Photos: Hollywood's steamiest sex scenes
'The Lover' (1992) – Jane March and Tony Leung Ka Fai star as a young girl and her older lover in "The Lover."
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Naomi Watts, left, and Laura Harring got hot and heavy in "Mulholland Drive."
Photos: Hollywood's steamiest sex scenes
'Mulholland Drive' (1996) – Naomi Watts, left, and Laura Harring got hot and heavy in "Mulholland Drive."
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