vagina facts
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1. During arousal, your lady parts act like his man parts.

You know about the clitoris "joy button" becoming more, um, button-y, but you may not be aware that the labia minora also contain erectile tissue that gets slightly stiffer when things heat up. The reasons for this go back to when you were a fetus with androgynous parts. "We all start out with the same tissues in that area," says Shelly Holmstrom, MD, associate professor of obstetrics and gynecology at the University of South Florida at Tampa.

2. Even the most mild-mannered among us have something in common with sharks.

Vaginal lubricant and shark liver oil both contain an organic compound called squalene. Squalene derived from sharks is sometimes added to moisturizers and skin creams, where it acts as an emollient.

3. Silicone lubricants may be right for you but not for your toys.

Gynecologists like Chicago's Lauren Streicher, MD, recommend silicone-based lubricants over water-based ones because they feel more natural, last much longer and don't usually contain propylene glycol, which is a potential irritant. However, silicone lubricant can compromise the integrity of vibrators and other sex toys that also contain silicone, and can cause them to change shape or break down

4. Menstrual blood may be a lifesaver.

For years, scientists have been trying to find a medically helpful use for menstrual blood, which contains stem cells that have the ability to regenerate. The latest, most exciting research: cells from this all-too-readily-available blood are currently being tested to see if they can help patients with heart failure.

Next: The truth about shaving and waxing down there