A Need to Nest

The "Nesting Instinct"

Your due date is getting closer, and suddenly you're feeling a burst of high energy -- and an inexplicable desire to clean every closet in the house. Or to color-code your baby's layette. Or maybe even to renovate your entire kitchen, which up until now has suited you just fine. What's going on? Relax! You're experiencing the infamous "nesting instinct," a domestic urge that can strike pregnant women around the start of the third trimester and intensify in the days before birth. Weird? Definitely. But it's a very real phenomenon -- and knowing why it happens and how to keep it in check will make preparing for your new little one a healthy, stress-free, and enjoyable experience.

Blame It on Biology

All female mammals begin preparing their surroundings for a newborn in advance of its birth -- and humans are no exception. "It's nature's way of ensuring that the environment we bring a child into will be safe, warm, and welcoming," says Parents advisor Hilda Hutcherson, MD, clinical professor of obstetrics and gynecology at Columbia University, in New York City. No one knows exactly what prompts the behavior, but experts suspect that hormones play a big role. "During pregnancy, your body produces increasing amounts of oxytocin and prolactin, both of which are thought to be responsible for maternal bonding," says Louann Brizendine, MD, director of the Women's Mood & Hormone Clinic at the University of California at San Francisco and author of The Female Brain. "These hormones reach peak levels in the last month of pregnancy." Other medical experts attribute nesting to a primal instinct that harks back to a time when physical preparation of one's surroundings was necessary for a safer childbirth.