Here's what is known about human sex and sexuality in the physical, mental and emotional realms. LiveScience examines the latest psychological, biological and sociological studies on sex, ranging from dating and mating, to flirting and cheating, to birth control and STDs.
Latest about Science of Sex
How to tell you're in love with someone, according to science
Reference Your brain and behaviors tell you you're in love in a variety of ways. Here's 14 signs you've been struck by Cupid.
3 Reasons You Might Hate Valentine's Day
Valentine's Day may be one of the most polarizing holidays on the calendar. Here's why it's hated.
Syphilis Cases Surge Among US Newborns, Reaching 20-Year High
A resurgence of syphilis in the United States has led to a dramatic spike in cases of the disease among newborns, according to a new report.
WWI POW's Romantic Engraving Discovered 100 Years Later
More than 100 years ago, a Russian soldier held captive in a prisoner-of-war camp engraved a beautiful scene on an aluminum canteen showing two people, deeply in love, snuggling together.
Video Shows How HIV Infects Cells During Sex
A new video shows the virus passing from an infected cell into a new host, as it would during sexual transmission.
You Have a Second Immune System, and It Might Be Ruining Your Love Life
In the battle against germs, your immune system is the best wing-man there is. When it comes to dating? Not so much.
UK Man with 'Worst Ever' Drug-Resistant Gonorrhea Is Now Cured
The U.K. man who caught the "worst ever" case of antibiotic-resistant gonorrhea has been cured.
Gonorrhea's Always Bad, But This Man's Case Might Be the 'Worst Ever'
This could be the "worst ever" case of antibiotic-resistant gonorrhea that doctors have seen.
