Puberty is a confusing time. Your hormones are all over the place, you don’t fit into the clothes that you did two months ago and last but not the least, you don’t know what to do about the breasts that are expanding- at their own pace- on your chest. The first time I had to put on a bra, and for a long time after actually, I dreaded it. Training bras in India are basically less comfortable sports bras, and because you’re not familiar with the entirely confusing world of lingerie yet, it can be a bit overwhelming.

Not to mention, your breasts never give you notice when they jump up a size! (or two) So for those of you that have wondered, and those of you who are still questioning the growth of your breasts, this one is for you! And remember, like with most other things in life, breast development isn’t set in stone; the way yours develop will vary from the way another woman’s does. Everything from when your breasts start to grow, to what size they become and how various life stages affect them, depends on many different factors, like genetics and individual body chemistry.

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Breast development actually begins before birth, with the creation of the milk-duct system, and the process continues internally throughout your childhood as the breast tissue and mammary glands mature. It is not until puberty though, when the first external signs of breast development appear; they are triggered when the ovaries release oxygen and your secretory glands are formed when your menstruation begins. Your breasts get bigger as the duct and gland systems continue to grow and the fatty connective tissue accumulates. If you haven’t noticed, and this is common amongst most women, menstruation affects breast size on a monthly basis as well; increased level of estrogen and progesterone stimulate the milk glands every month -to prepare for possible pregnancy- and in some women, this results in swollen or enlarged breasts. However, if there’s no pregnancy, they generally go back to normal after your period ends. 

Many women find that their breasts reach their final, adult size in their early 20s, but others have a different experience, especially when pregnancy and childbirth are taken into account. According to a medical report released by John Hopkins, the renowned American institute, some doctors don’t consider breasts to be fully developed until a woman has actually produced milk and/or given birth. Some pregnant women experience an exponential growth of their breasts, due to the increase in progesterone levels in the body and further development of the milk duct system, while others only increase a couple of sizes. And while it’s possible for breasts to return to their pre-pregnancy size once a woman is done breastfeeding, it’s not always the case; some women retain their pregnancy breast size even after they stop doing so. 

However, according to the same medical report that was released, the mammary glands start to shrink for most women around the age of 35, and this is the last developmental stage that occurs (unless one experiences a big physical change). This is mainly due to the onset of menopause; our hormones go a bit haywire and the estrogen levels drop significantly, resulting in this shrinkage; the shrinking of glands and the change in hormone and tissue levels make breasts less dense. Due to all of these changes that are taking place in your body, the way your breasts develop will be affected as well. You might notice not only a change in size, but also a change in shape, but that is entirely normal. Your body is simply going through a cycle, and it will bring about different physiological changes, and your breasts are just one of the many that will happen throughout the course of your lifetime.