Some girls may notice physical

Cramps, PMS, and Pimples Some girls may notice physical or emotional changes around the time of their periods. Menstrual cramps are pretty common - in fact, more than half of all women who menstruate say they have cramps during the first few days of their periods. Doctors think that cramps are caused by prostaglandin, a chemical that causes the muscles of the uterus to contract.
Depending on the person, menstrual cramps can be dull and achy or sharp and intense, and they can sometimes be felt in the back or the thighs as well as the abdomen. These cramps often become less uncomfortable and sometimes even disappear completely as a girl gets older. In the meantime, many girls and women find that over-the-counter pain medications (like acetaminophen or ibuprofen) can relieve cramps, as can taking a warm bath or applying a warm heating pad to the lower abdomen. Exercising regularly throughout the monthly cycle may help lessen cramps, too. If these things don't help, ask your doctor for advice.
Some girls and women find that they feel depressed or easily irritated during the few days or week before their periods. Others may get angry more quickly than normal or cry more than usual. Some girls crave certain foods. These types of emotional changes may be the result of premenstrual syndrome (PMS).
PMS is related to changes in the body's hormones. As hormone levels rise and fall during a woman's menstrual cycle, they can affect the way she feels, both emotionally and physically. Some girls, in addition to feeling more intense emotions than they usually do, notice physical changes along with their periods - some feel bloated or puffy because of water retention, others notice swollen and sore breasts, and some get headaches. PMS usually goes away soon after a period begins, but it can come back month after month. Doctors recommend that girls with PMS try to exercise to help feel better. And some girls notice that restricting caffeine intake may help relieve PMS.
It's not uncommon for girls to have an acne flare-up during certain times of their cycle; again, this is due to hormones. Fortunately, the pimples associated with periods tend to become less of a problem as girls get older.
Pads, Tampons, and LinersOnce you begin menstruating, you'll need to use something to absorb the blood - either a pad or a tampon. There are so many products out there that it may take some experimenting before you find the one that works best for you. Some girls use only pads (particularly when they first start menstruating), some use only tampons, and some girls switch around - tampons during the day and pads at night, for example. Girls who are very active, particularly girls who enjoy swimming, often find that tampons are the best option during sports.
Periods shouldn't get in the way of exercising, having fun, and enjoying life. If you have questions about pads, tampons, or coping with periods, ask a parent, health teacher, school nurse, or older sister. Online resources are available with answers to some of your most personal questions - click on the Resources tab at the right for some suggestions.