About how big are your breasts when you get first period?

Breast development typically begins around the age of 10-11 in girls, and can continue to develop for several years after the onset of menstruation. The size of breasts at first period can vary greatly from girl to girl, and is influenced by factors such as genetics, nutrition, and overall body development. On average, breasts may be around A-cup size or slightly larger at the time of first period, but this can vary significantly. It's important to remember that breast size is a normal part of female development and can vary greatly among individuals, and there is no "right" or "wrong" size.