Early cord clamping—almost immediately after birth—has been the standard procedure for decades, but new research suggests that waiting before clamping is better for baby. A 2013 review of 15 medical studies found that waiting to cut the cord improved babies’ birth weight, blood concentration and iron stores at 6 months of age without increasing moms’ risk of bleeding.

“When babies are born, whether by caesarean or vaginal birth, they’re squeezed to some extent, and the pressure changes can cause of some of baby’s blood volume to become trapped in the placenta,” explains Stuart Fischbein, MD, co-author of Fearless Pregnancy: Wisdom and Reassurance from the Doctor, a Midwife, and a Mom. “So if you clamp the cord immediately, you’re depriving baby some of its normal blood volume. By delaying cord clamping, you allow baby to equilibrate. It’s much more natural to let the cord pulsate until it stops because that helps baby make an easy transition; he’s still getting nourishment and oxygen from the mother while learning to breathe.”

But that doesn’t mean you’ll be connected to baby forever. It can take anywhere from a minute to 30 minutes or so for the cord to stop pulsating. Delaying cord clamping and cutting, even if just for a minute or two, may decrease the chances of aby developing iron-deficiency anemia and improve his overall health.

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