The Truth Behind Women's Brains PART 4

[Juan and Yenan]

The Truth Behind Women's Brains
20/20's Elizabeth Vargas Looks at the Chemical Changes That Occur Through Life That Change How Men and Women Think

Studies have shown that, within about 48 hours or so, a mom can pick out the cry of her own baby above other babies. It could be that human evolution has been hard-wired in some ways to protect infants and propagate the species.

A similarly dramatic hormonal effect is experienced when mothers breastfeed. As she nurses, oxytocin, the feel-good hormone, marinates a mother's brain. Many women say they are awash in feelings of warmth and pleasure. According to Dr. Brizendine, "some women even say they almost have an orgasm while they're breast feeding -- that they can feel their uterus contracting."

Because of this, Dr. Brizendine suggests that it's no wonder that the mommy brain has little desire for sexual contact -- the baby is now her primary love interest, and the intense hormonal focus on her child leaves her satisfied, but exhausted.

"Having a baby definitely changes your sex life," said Cheyette. "The baby is taking up time and energy and brain space, and I think it's hard for a woman to get in the mood."

"The dad is there only in a supporting role now," adds Dr. Brizendine, "Whereas he's been used to being the main course, he's now like a side dish."

For many women, their child-centric behavior not only compromises their relationships, but also their jobs. Hormonally tethered to their child the interest of some mothers to return to work is often challenging.

"It's a struggle I live with everyday. Being at work, sometimes I feel guilty about being there. Sometimes being at home, I feel like I should be at work," said Cheyette. "And it's not just me, it's every mom that I know."

Balancing work, pregnancy and then family is a struggle for most women, and Dr. Brizendine hopes her book and research bring awareness about the difference between male and female brains.

Sarah Cheyette agrees: "For our children's sake, and for their children's sake, it would be best if people understood pregnant women, pregnancy and what being a mommy is about."