Medically reviewed by Cordelia Nwankwo, MD Key Takeaways Breast development usually starts about two years before the first period. Emotional changes and mood swings can occur just before the period.

The first few times you get your period, it’s totally normal to feel caught off-guard. (But, ofc, not ideal.) In fact, irregular periods are super common in the beginning. Your body isn’t ovulating ...

Bloating, cramping, and headaches are just a few of the common symptoms of premenstrual syndrome (PMS). The most common cause for PMS is a drop in hormones. Typically these symptoms last about a week ...

Add Yahoo as a preferred source to see more of our stories on Google. Periods are triggered by a drop in hormone levels in your body, specifically estrogen and progesterone, Dr. Anita Somani, ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." The first few times you get your period, it’s totally normal to feel caught off-guard. (But, ofc, not ...