6 Reasons You Might Miss Your Period When You’re Definitely Not Pregnant

For collegiettes, a late or missed period can instantly lead to panic. It’s easy to jump to the unsettling conclusion that sets up the conflict in so many rom-coms: an unplanned pregnancy. But what if that’s just not possible? Like, logically you have not had sex recently enough (or ever) to be pregnant. Cue the sigh of relief. But wait—what’s up with your period then? We don’t blame you if you don’t miss your fave monthly visitor, but it’s still good to make sure everything is a-okay with your body. We asked a board-certified gynecologist and women’s health expert to help us out. Dr. Sara Gottfried is the three-time New York Times bestselling author of The Hormone Cure and The Hormone Reset Diet, and her latest, Younger.

1. Stress

Stress causes an increase in some hormone levels, specifically cortisol (a steroid hormone that regulates many bodily processes like your metabolism and immune system) and it’s no secret that periods and hormones are closely tied. Dr. Gottfried explains that when your cortisol levels are high, non-essential bodily functions stop in order to focus on preparing your brain and body to address the stress. “Think of the stress as causing a temporary malfunctioning of the hypothalamus, the part of your brain that controls your hormones,” Dr. Gottfried says. “Excess cortisol can thereby suppress the hormones controlling the menstrual cycle, blocking ovulation [and] making your period stop, a condition known as secondary amenorrhea.”

Since college can be incredibly stressful for so many people, it’s not really surprising that a student might miss her period during particularly tough times, like finals week or midterms. Once your life settles down, your period should come back.

2. Changes in weight

Fluctuation in weight can also impact your menstrual cycle for the same reason that stress does. “Losing or gaining weight is considered a stressor, and when you’re stressed, your body’s hormonal feedback loops are trained to suppress nonessential functions, like reproduction and your period,” Dr. Gottfried says. For someone who’s underweight or dieting, the part of the brain that controls estrogen levels is under a lot of stress and might not release enough to prep the body for reproduction, hence no period.

“Estrogen is what builds up the lining of the uterus, so without sufficient estrogen, your period may be late or stop,” Dr. Gottfried says. Because of this, many women with eating disorders don’t get a period at all. Similarly, being overweight or suddenly gaining weight causes hormone imbalances that don’t bode well for reproduction either. Maintaining a regular, healthy diet will help keep a normal flow too. “Lose weight slowly on a sound nutritional program. Don’t do a fad diet that drops weight too fast,” Dr. Gottfried recommends. “Healthy weight loss is 0.5 to 2 pounds per week, and less after the first one to two weeks.”

Related: 5 Reasons You Might Be Experiencing Pain During Sex

3. Excessive exercise

It feels nice when you’re finally motivated to work out, but if you're feeling yourself so much that you hit the gym for hours every day, you could be disrupting your flow. Exercise is good for you, but an unhealthy amount of it can change more than your abs. Many gymnasts and runners do not have a period because of the effects of excessive working out, like higher stress levels, increased energy usage and low body fat.

“Intense exercise is another stressor, so it works by the same mechanism of suppressing the hypothalamus and normal hormone production,” Dr. Gottfried says. It might sound nice at first: getting in shape and skipping your period? Score. But be wary of throwing off your flow for too long. Three or more missed periods in a row is officially considered amenorrhea and if you’re at that point, you might be putting your body under too much stress.

4. New meds

A lot of medications have hormonal side effects, which, in turn, affect your period. For example, some antidepressants or blood pressure pills could stop menstruation. Double check the side effects for any medication you’re taking and ask your doctor if your reproductive cycle doesn't adjust. Another possibility? Certain birth controls affect periods differently. If you messed up taking the pill or switched forms of birth control recently, it could cause your period to take a pass for the month.

5. Human error

Some of us know about the time our period should start, but if we don’t pay close attention it’s hard to say when exactly we’re actually late. Maybe you simply miscalculated. If you’re unsure about the exact length in between your cycles or when your last period was, try downloading an app that monitors your menstruation, like "Period Tracker" or “Clue.” Also, even if it seems like you haven’t had sex in a while, double check that too. “If you go more than 35 days without a period and you’re sexually active, check a pregnancy test,” Dr. Gottfried says.

6. Feeling under the weather

Short-term and chronic illnesses can both delay your period. If your body is really not in its best shape, it won’t want to create a baby in that moment, so it won’t ovulate, forgoing the menstrual cycle for that month. If you begin to continually miss your period, you should go to the doctor to determine if you have a more serious condition. Dr. Gottfried says chronic health issues can also cause abnormal cycles. These include hypothyroidism, Polycystic ovary syndrome, which is a hormone imbalance often accompanied with small cysts on the ovaries, or genetic conditions like Turner syndrome where a female has only one X chromosome.

Sometimes it’s nice to have a month off of insane cramps, worrisome leaks and raging PMS, and a lot of the time it’s probably not due to anything super serious. Changes in your health and body can lead to temporary and totally safe disruptions in your cycle. But in the end, periods are a normal and healthy part of life. As delightful as it would be to not deal with the mess of menstruation, if you continually miss your period you should take a trip to your doc’s office and figure out what’s up.