*Fairly* common. Can't give you a number, but it's certainly not rare.
The cure is to stretch them out - by suction. There is a device called a "Niplette" marketed for this purpose which is good because you wear it (them) for many minutes or hours each day so - like braces on teeth - they slowly cause the nipples to grow out the way you want.
Of course, having an agreeable fellow do this for you frequently every day would be of some benefit too. Although a healthy baby will eventually achieve this for you, you really want them to be in order *before* you need them for breast feeding.
And of course the warning - outside of puberty, if they *were* normal and become inverted later, you *really* need to see the doctor. Cancer is not the only cause of ("secondary") nipple inversion, but you have to make sure.
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Oh, and - do check out my *comments* regarding your question on men peeing with an erection!
The cure is to stretch them out - by suction. There is a device called a "Niplette" marketed for this purpose which is good because you wear it (them) for many minutes or hours each day so - like braces on teeth - they slowly cause the nipples to grow out the way you want.
Of course, having an agreeable fellow do this for you frequently every day would be of some benefit too. Although a healthy baby will eventually achieve this for you, you really want them to be in order *before* you need them for breast feeding.
And of course the warning - outside of puberty, if they *were* normal and become inverted later, you *really* need to see the doctor. Cancer is not the only cause of ("secondary") nipple inversion, but you have to make sure.
------------
Oh, and - do check out my *comments* regarding your question on men peeing with an erection!