As human beings, we like consistency—we love for the bus to show up on time, for our paychecks to come on a regular schedule, and for our periods to come right on time, every time. Schedules are helpful for our brains; they take the guesswork out of planning for the future and help reduce stress when we know what to expect.
But then the inevitable occurs—the expected day of your period comes and goes and nothing happens. Maybe you notice it immediately or it takes you a week to realize it, but when you notice that your period is late, it can cause a flood of thoughts. But not every missed period means the same thing! There are a wide array of reasons for a late or missed period and we’re going to explore the five most common reasons today.
1. Sudden Weight Change
Your body is accustomed to menstruating when you’re at a consistent weight and gradual weight changes are not likely to affect your periods. However if you gain or lose weight in a short period, your periods may stop temporarily. This is especially true when you lose a lot of weight quickly; a sudden calorie deficit can cause your body to stop producing the hormones needed for ovulation (egg development and release).
2. Polycystic ovary syndrome (PCOS)
PCOS occurs in 8%-13% of women in reproductive age and occurs when ovarian cysts (fluid-filled sacs) develop on the ovaries and prevent your eggs from maturing. Ovulation may be inconsistent which leads to inconsistent and missed periods. See a doctor if you believe you have PCOS or have experienced prolonged periods without your period.
3. Maintained, High Stress Levels
Our body’s have an age-old stress response that functions to keep us safe and to keep critical body functions going in the case of a crisis. During a period of prolonged, elevated stress levels, our bodies go into crisis mode, causing the brain to tell our endocrine system to release cortisol, the stress hormone that suppresses functions like the reproductive system. If you stay in a stressful state for a long time, your body will continue to suppress ovulation and menstruation until your cortisol levels decrease to bring you to a more peaceful state of mind and body.
4. Increased Physical Exercise
Whether you’re exercising more as a byproduct of your job or for recreation, you’re probably seeing a number of benefits like more energy and better sleep. However, if you continue to eat less while exercising too much, your metabolism may slow down normal functions to conserve energy. During this slow down, bodily functions essential for survival will continue but ovulation may stop temporarily. As a result, your periods may stop until you arrive at a healthy balance of caloric intake and output.
5. Pregnancy and Breastfeeding
Periods occur when there isn’t a successful fertilization of an egg from sperm. However, if unprotected sex or a contraceptive failure occurs, sperm can be successfully introduced to an egg leading to pregnancy and stopping your period for at least 9 months.
In the same vein, if you breastfeed your newborn, you may experience the same kind of temporary period loss as a woman who’s simply over-exercising. While breastfeeding, your body exerts more energy than usual, leading to your metabolism slowing down and your period stopping temporarily. This isn’t true of all breastfeeding mothers, though. Many women get their periods within a month of giving birth, but for many others, their period stops during the time they’re breastfeeding.
All in all, there are several common reasons you may have missed your period. If you’ve had unprotected sex in the last month and your pregnancy test comes back negative, we recommend checking in with your doctor. They’ll be best able to help you identify the reason for your period delay and offer solutions in case there’s a medical condition that needs to be addressed.
