Worried about a late period, but know you’re not pregnant? Missed or late periods happen for many reasons other than pregnancy. Common causes can range from hormonal imbalances to serious medical conditions.
There are also two times in a woman’s life when it’s totally normal for her period to be irregular: when it first begins, and when menopause starts. As your body goes through the transition, your normal cycle can become irregular.
Most women who haven’t reached menopause usually have a period every 28 days. However, a healthy menstrual cycle can range from every 21 to 35 days. If your period doesn’t fall within these ranges, it could be because of one of the following reasons.
Stress can throw off your hormones, change your daily routine, and even affect the part of your brain responsible for regulating your period — your hypothalamus. Over time, stress can lead to illness or sudden weight gain or loss, all of which can impact your cycle.
Women with eating disorders, such as anorexia nervosa or bulimia, may experience missed periods. Weighing 10 percent below what’s considered a normal range for your height can change the way your body functions and stop ovulation. Getting treatment for your eating disorder and putting on weight in a healthy way can return your cycle to normal. Women who participate in extreme exercise such as marathons may stop their periods as well.
Just as low body weight can cause hormonal changes, so can being overweight. Your doctor will recommend a diet and exercise plan if they determine that obesity is a factor in your late or missed periods.
Polycystic ovary syndrome (PCOS) is a condition that causes your body to produce more of the male hormone androgen. Cysts form on the ovaries as a result of this hormone imbalance. This can make ovulation irregular or stop it altogether.
Other hormones, such as insulin, can also get out of balance. This is due to insulin resistance, which is associated with PCOS. Treatment for PCOS focuses on relieving symptoms. Your doctor may prescribe birth control or other medication to help regulate your cycle.
You may experience a change in your cycle when you go on or off birth control. Birth control pills contain the hormones estrogen and progestin, which prevent your ovaries from releasing eggs. It can take up to six months for your cycle to become consistent again after stopping the pill. Other types of contraceptives that are implanted or injected can cause missed periods as well.
Chronic diseases such as diabetes and celiac disease also can affect your menstrual cycle. Changes in blood sugar are linked to hormonal changes, so even though it’s rare, poorly controlled diabetes could cause your period to be irregular.
Celiac disease causes inflammation that can lead to damage in your small intestine, which may prevent your body from absorbing key nutrients. This can cause late or missed periods.
Most women begin menopause between ages 45 to 55. Women who develop symptoms around age 40 or earlier are considered to have early peri-menopause. This means your egg supply is winding down, and the result will be missed periods and eventually the end of menstruation.
An overactive or underactive thyroid gland could also be the cause of late or missed periods. The thyroid regulates your body’s metabolism, so hormone levels can be affected as well. Thyroid issues can usually be treated with medication. After treatment, your period will likely return to normal.
Your doctor can properly diagnose the reason for your late or missed period and discuss your treatment options. Keep a record of changes in your cycle as well as other health changes to show your doctor. This will help them make a diagnosis.
If you have the following symptoms, contact a doctor right away:
- unusually heavy bleeding
- severe pain
- nausea and vomiting
- bleeding that lasts longer than seven days
- bleeding after you’ve already entered menopause and had not periods for a year
If you don’t already have an OBGYN, you can browse doctors in your area through the Healthline FindCare tool.