Why Did I Stop Getting My Period?

Learn what normal periods are and find out what can cause your period to stop.

Sanaz Majd, MD
5-minute read

Sharon came to see me for a routine pap smear examination. I asked her if she had any topics that she wanted to discuss during our visit, and she replied, “Nope! Everything’s perfect! In fact, even better than perfect since I no longer get my periods!” 

Sharon is 28 years old and clearly not in menopause yet. So you can imagine why I was so surprised to hear that she was actually happy to no longer get her periods. OK, maybe I wasn’t too surprised, since I realize how inconvenient it is for many of us during those few days out of the month. But at the same time, I was a little more concerned than Sharon was because I knew that this is not normal for her age. 

Sharon then admitted that she hadn’t had a period since over a year ago. But it never occurred to her to get it checked out since she was enjoying its absence. “I no longer have to buy feminine products!” she exclaimed.

What Is a Normal Period?

Before we can understand what is abnormal, we need to define what is actually normal since there is huge variation. Here is how us docs characterize periods and decide if they are “normal”:

  • Age range: First of all, most women tend to start getting their periods, a term referred to as menarche, sometime between age 9 and 15. If menarche does not occur in this age range, then this is not considered normal. 

  • Cycle: Second, a cycle is defined as the number of days between the first day of your bleeding until the first day of your next period. A normal cycle can range anywhere between 21 and 35 days. 

  • Duration: Normal periods also have a duration of 2 to 7 days. 

  • Flow: Lastly, the amount of bleeding, or flow, can be normally quite variable for different women. However, if you notice a significant change in the amount of flow compared to your previous periods, it could be a sign of abnormal flow. 

In Sharon’s case, her periods were totally normal until she all of a sudden stopped menstruating at age 28. What happened to Sharon’s body that caused this to happen? Well, in order to ask her the right questions, I have to remind myself of all the possible causes of amenorrhea, the fancy term used to describe the lack of periods for at least 3 consecutive months.

What Can Cause Periods to Stop?

Here are some of the more common causes of amenorrhea, and the questions that I need to ask Sharon to find out why her periods have stopped:

  • Pregnancy: Is Sharon sexually active? Pregnancy is by far the most common cause of amenorrhea. As obvious as it may seem, it can be easily missed at the doctor’s office! Just because you don’t get your periods, it doesn’t mean you can’t get pregnant! Sharon pregnancy test was negative, however.

  • Stress: Sure, we tend to blame a lot on stress these days. However, there really is a physiologic phenomenon called “Hypothalamic-Pituitary Amenorrhea,” a term referred to the absence of periods due to hormone changes in the brain that tell the female body parts that you are too stressed out to have a baby. And your periods will stop in response. Sharon says she’s actually been less stressed out than usual since she’s adopted an adorable new puppy that she recently saved from the pound.

  • Eating Disorders: What is Sharon’s nutrition like? I have to make sure that she is not suffering from an eating disorder, such as Anorexia or Bulimia, as these disorders also tell the brain that you are not healthy enough to carry a pregnancy, thereby shutting down your periods.  Sharon happens to be a healthy vegetarian who eats five balanced smaller meals a day.

  • Polycystic Ovarian Syndrome (PCOS): This is a common health condition that is caused by elevated testosterone levels, a hormone that causes excess body hair, weight gain, acne, and problems with periods (see my prior post on “Why Am I So Hairy” to learn more). Sharon does not suffer from excess body hair or acne, and is not overweight. In fact, if anything, she seems to be a tad underweight at 110 pounds at 5’5 tall.  Still, since few women with PCOS may present atypically, a blood test that I performed further supported my suspicions that Sharon does not suffer from PCOS.

  • Hormonal Conditions: Besides PCOS, there are a few other less common health conditions, such as thyroid disorders and disorders that cause an elevation in the hormone called “prolactin,” that may cause amenorrhea. These disorders can easily be tested through a simple blood test, and Sharon’s tests were normal.

  • Medications: I asked Sharon if she was taking any medications, such as birth control, steroids, or anti-psychotic medications, that could possibly be causing her periods to go out of wack, but she denied any recent use. In fact, she only takes a multivitamin a day.

  • Uterine Problems: I also made sure to ask Sharon if she has ever had any procedures performed on her uterus and about any history of Endometritis, a serious infection of the uterus. Sharon has never experienced any such problems with her uterus, thankfully, as these conditions may cause period irregularities.

  • Vigorous Exercise: Exercise is great for our hearts and our bodies. However, like everything in excess, it may do more harm than good. When I asked Sharon about her activity level, she admitted that she had started a strict exercise regimen in the past one year in preparation for an upcoming marathon next month. She had never run a marathon before, but being the animal lover that she is, she signed up for a marathon to help raise money for animal awareness.


Please note that all content here is strictly for informational purposes only. This content does not substitute any medical advice, and does not replace any medical judgment or reasoning by your own personal health provider. Please always seek a licensed physician in your area regarding all health related questions and issues.

About the Author

Sanaz Majd, MD

Dr. Sanaz Majd is a board-certified Family Medicine physician who graduated from Drexel University College of Medicine in Philadelphia. Her special interests are women's health and patient education.