Estrogen

Estrogen is a hormone - a special chemical that helps your body do different things, like grow and change. Estrogen helps girls when they start to become women. Estrogen helps your body do things like make your hips wider, grow breasts, and have a period. Without estrogen, girls' bodies would not change the way they do. Estrogen is also important for moms who have babies - it helps make milk. Too much or too little estrogen can make you feel sick, but the right amount helps keep you healthy and strong.