What To Know About Leaky Nipples in Pregnancy

Bodies can change in all sorts of unexpected ways during pregnancy. But for some people, there's a particularly surprising issue they didn't expect to deal with before the baby arrives: nipple discharge, a yellow or clear liquid coming out of the breast when it's squeezed (or for no apparent reason at all). You rarely hear about it, but it's more common than you think.

Read on to learn more about why your nipples may leak during pregnancy and how to keep your breasts, chest, and clothing dry while you're expecting.

What Causes Nipples to Leak During Pregnancy?

Many pregnant people outgrow their bras well before their pants. That's because breasts begin changing to prepare for breastfeeding or chestfeeding early on in pregnancy. During the first trimester, the glands in the breasts that produce breast milk grow rapidly.

Chalk it all up to shifting pregnancy hormones. "During pregnancy, your body releases prolactin, a key hormone that promotes milk production," says Patrick Duff, MD, associate dean of the obstetrics and gynecology department at the University of Florida in Gainesville.

As your pregnancy progresses, your prolactin levels start to surge. Between weeks 12 and 16 of pregnancy, your breasts start to produce colostrum, an early form of milk that's creamy white or yellow in color. Colostrum is high in protein and contains antibodies that protect your newborn against infection.

While all of this is happening, estrogen and progesterone made by the placenta are working to prevent your body from secreting milk until the baby arrives. But sometimes the balance between all of these hormones is off. "It's like having your foot on the gas and the brakes at the same time—sometimes the accelerator overrides the stopping mechanism," says Dr. Duff. "And a little bit of milk can leak out."

When Nipples Might Leak

While your body begins to make milk late in the first trimester of pregnancy, your breasts don't start developing the ability to secrete it until the second trimester. (Doctors call these stages lactogenesis I and lactogenesis II). So a little leaking in pregnancy, if it happens at all, most likely would occur later in pregnancy. "Seeing a few drops of liquid is normal," emphasizes Sharon Phelan, MD, a professor emeritus of obstetrics and gynecology at the University of New Mexico School of Medicine in Albuquerque.

Leaking will typically be triggered when your nipples are stimulated. That can happen during foreplay or when you're taking part in activities that cause your nipples to rub against your clothing (say, a brisk walk or an exercise class). But you could notice a few drops of moisture in your bra or against your clothing for no reason at all, especially as you get closer to your due date.

How To Prevent Leaky Nipples

There's not much you can do to keep your nipples from leaking during pregnancy, but you can help to control an unexpected flow during pregnancy and after the baby arrives.

Before leaking (or later, nursing or pumping), many people experience a tingling sensation that accompanies the initial release of milk. If you are in a moment (perhaps an important meeting) in which you want to control any leakage, you can use your arms to apply slight pressure to your chest area, which may slow this "letdown reflex."

Leaking during pregnancy is usually mild—just a few drops here and there—but if you find yourself with wet bras or shirts when pregnant or during breastfeeding, you may want to wear nursing pads inside your bra to prevent spots (and maybe save a little on your dry cleaning bill).

When To See a Doctor About Leaky Nipples

If you're leaking more than a few drops from one or both nipples or if you're noticing a thick discharge or spots of blood, it's a good idea to make an appointment with a health care provider. Most of the time, this discharge is due to normal milk duct development, but it can also indicate a clogged milk duct that can easily be treated by your doctor, says Dr. Duff.