Throughout pregnancy and childbirth, your breasts have probably stretched, swelled and leaked more times than you care to remember. And after you finish weaning, you may notice that they look different than before — in size, shape and even appearance.

But is breastfeeding really to blame? Not entirely. Here’s what’s really going on with your breasts after breastfeeding.

Will my breasts change after breastfeeding?

Your breasts may look noticeably different after you finish breastfeeding, but nursing isn’t necessarily the reason. In fact, these changes have likely been taking place for a year or two — ever since the early stages of your pregnancy.

Within weeks of conceiving, your body starts preparing for lactation by ramping up the production of pregnancy hormones like estrogen and progesterone, which causes more fatty tissue to build up in the breasts and boosts blood flow to the area.

As your breasts continue to grow (sometimes by multiple cup sizes), the underlying ligaments also begin to stretch, which is one reason they might appear less elastic after you give birth. These changes can also be permanent — and they usually occur whether you breastfed or not.

The point is that even before you began nursing, your breasts had already begun this process (and accomplished some pretty amazing things along the way).

So it’s only natural that after you finish weaning — and after your body winds down its production of milk — your chest may seem a little, well, deflated.

How will breastfeeding change my breasts?

Chances are, your breasts grew throughout your pregnancy — so it may come as a surprise that on day three or four postpartum, your breasts can become temporarily engorged. The reason: After you pass the placenta, your body starts making prolactin, a hormone that kickstarts milk production.

If you’re not nursing, your breasts should start to shrink within a few days. If you are nursing, your breasts will probably continue to stay large, although you might notice they feel smaller after each feeding.

Once your baby starts on solid foods (usually around the 6-month mark, but sometimes earlier), your breasts will probably begin to shrink. After weaning, they should return to their pre-pregnancy size or close.

Can breastfeeding affect breast size?

Your breasts will probably return to their original cup size after you stop breastfeeding, although there’s also a chance they could get a little smaller than they used to be.

One study found that even though 73 percent of new moms noticed a difference in their breasts postpartum (most commonly, they were larger and less firm), those changes weren’t associated with breastfeeding. And according to other research, a woman's chance of having sagging breasts increased with each pregnancy, but it didn't seem to be affected by breastfeeding.

In fact, the American Academy of Pediatrics (AAP) says that age, gravity and weight gain are all more likely to cause changes in a woman’s breast size than breastfeeding.

While you can’t reverse the effects of aging, you can eat a healthy diet and exercise regularly, which will help you maintain a healthy weight. Quitting smoking if you do helps too, since smoking cigarettes reduces skin elasticity.

Can breastfeeding affect breast shape and appearance?

It’s not uncommon for your breasts to feel "lumpy" during pregnancy, in part because your body’s milk glands are growing in number and size — though if you feel a lump or anything really out of the ordinary, be sure to get it checked out by the doctor to confirm it's nothing more serious.

You also might notice a change in the consistency of your breast tissue, and your breasts may feel less firm than they once were. Those changes are again more likely due to pregnancy rather than breastfeeding.

During the first few weeks of breastfeeding, you may feel some tenderness in your nipples, which may also become cracked and sore. This could be caused by a poor breastfeeding latch, or your baby might just be an over-enthusiastic feeder.

In either case, it’s usually only a temporary problem. If your nipples are pink, itchy or crusty, however, you could have thrush, a common yeast infection that can be treated with antifungal medication. Cracked nipples can also lead to mastitis, a painful infection that can cause red, inflamed breasts as well as a fever and chills.

Is something wrong if there are no changes in my breasts after breastfeeding?

No. While many women find that their breasts change back to their pre-pregnancy size and shape after they stop breastfeeding, some women will notice a difference.

Some moms say their breasts stay larger after they’ve finished nursing, while others say they become smaller than they were before getting pregnant — which can be either a relief or a disappointment, depending.

Regardless, it’s perfectly normal not to notice a change in your breasts at all after breastfeeding. Getting used to the idea of your breasts as a source of nutrition for your baby is a big mental transition all on its own.

When to call the doctor about breast changes after breastfeeding

If you’re still nursing and you see red streaks on your breasts or feel painful lumps in them, you may have mastitis, an infection that develops when germs enter your body through a crack in the nipple or when your milk ducts become clogged. (Though again, get the lumps that do not resolve with massage, feeding or pumping over a couple days checked by your practitioner just to be safe.)

Other mastitis symptoms include a fever, chills or flu-like muscle aches — and they definitely warrant a call to your doctor too. Your practitioner can give you a diagnosis and will likely prescribe you a cycle of oral antibiotics, which will clear up the infection and ease the pain. And try to continue to breastfeed, if you can, since doing so can help drain the breast and clear up the infection.

Call your doctor, too, if during breastfeeding your nipples are sore or feel as if they're burning. This — along with nipples that appear shiny, itchy or crusty — could be a sign of thrush, a mild type of yeast infection.

If you have thrush, your little one may also develop an oral yeast infection that appears as white or yellow patches or sores along her tongue or gums. Your doctor will probably give you a prescription for antifungal medication, which should clear up the infection in about a week.

The many changes your body goes through during pregnancy and the postpartum period can be a lot to take in, but know that if you do decide to nurse, breastfeeding will ultimately benefit both you and your baby.