In her first pregnancy, Lauren O’Connell* didn’t need a positive test to confirm she had a bun in the oven—her boobs told her. She’d always had small breasts and rarely experienced pain with her cycle, but then over the course of a couple of weeks, she was popping out of her tried-and-trusted padded bras and couldn’t stand having anything—not fabric, not the shower, not her husband—touching her chest. “I couldn’t wear a bra most days: My boobs were way too sore,” says the mom of three from Vancouver. With every subsequent pregnancy, her breasts were always the telltale sign, before the second line appeared.
Any woman who is trying to conceive has been there, poking and prodding her breasts to see if they are fuller or more painful than usual, hoping for signs of a maybe baby. What breast changes should women expect in pregnancy? And what’s actually happening in there? Well, it’s all kind of magical (though it may not feel that way).
1. They get big and sore
In early pregnancy, the hormonal dream team of human chorionic gonadotropin (hCG) and progesterone ramp up, preparing your breasts for eventually feeding your baby. “You’re getting more glands, which accounts for most of the growth,” says Katrina Sawatsky, a family physician with a maternity practice in Calgary. Increased fat buildup and blood flow also factor in, but most of the work is done by the pregnancy hormones, which are also to blame for the soreness—much like the tenderness you might get before your period.
2. They take on new characteristics
O’Connell remembers catching a glimpse of herself getting out of the shower and being alarmed by the dark blue veins crisscrossing her breasts. “My boobs looked like a road map,” she says. Veins are actually more pronounced all over your body during pregnancy, especially if you have fair skin, but it’s most noticeable on your breasts, and it can be blamed on an increase in blood volume that occurs in pregnancy. While most of the veins will go back to normal post-delivery, if you breastfeed, those on your breasts will stay pronounced until you wean (because while the blood volume in your body goes down, the blood flow to your breasts remains higher than usual during breastfeeding).
3. Your nipples transform
Your areolas (the larger area around your nipples) may darken and widen, thanks to an increase in the hormone melanin, and the Montgomery’s tubercles (the little bumps on your areolas, which are actually oil glands) will become more obvious, gearing up to provide necessary lubrication for breastfeeding. The oil they secrete is also a natural antiseptic for the nipple.
4. They start to make colostrum as early as 32 weeks
Often termed “liquid gold” for its concentrated levels of antibodies and nutrients, colostrum is the first food your baby will eat before your mature milk comes in. You might find you leak a bit of colostrum before giving birth—this is totally normal. Consider tossing breast pads in your purse as you get closer to your due date. But don’t worry if you don’t see any colostrum before your baby is born—it doesn’t have any correlation to breastfeeding success.
5. The fullness doesn’t last
O’Connell describes her boobs as “pancakes” after having three kids: “They’ve lost their volume. They’re really flat. My bras are more padded than ever.” The glands you develop during pregnancy involute (meaning they shrink inward) after weaning, but the skin has been stretched to accommodate the initial enlargement. Depending on your breasts before you got pregnant and how much they changed during pregnancy, that may mean a loss of fullness and some sagging. “It’s all genetics,” says Sawatsky. “Blame your mom.”