Why Is My Period So Long? Dear Iris, A friend of mine seems to have a long menstrual cycle, with each month between approximately 33 days and 43 days. In other words, between January and February it was 33 days, between February and March 43 days, between March and April 33 days, and so on. Is this normal and what is the explanation for it? If it makes a difference, she's 20 years old. Sincerely, PJ --- Dear PJ, Each woman is unique and what is normal for one woman may not be normal for another. Your friend has a long cycle, true, but it may be absolutely fine for her. Ask her to contact her doctor and make an appointment for a gynecological exam. When in the doctor's office, she can review her menstrual history and ask what the doctor recommends. The real question is: When does your friend ovulate? That's what she'll need to know to practice effective contraception or to become pregnant. Take care, Iris Questions about why is my period so long? Get answers, tips, and advice at BeingGirl.com.