If you've missed a period or you've found that it's shorter or longer than normal, it's easy to jump to conclusions. However, an abnormal period isn't always a cause for alarm, as a number of everyday things can affect your menstrual cycle — even if it's something you would least expect. Some people may be more sensitive to change than others, but that doesn't automatically mean you have some scary disease or are going to have a baby. Sometimes it's something much more mundane.
Menstruating people experience between 11 and 13 menstrual cycles per year, averaging a 28-day cycle, but each person is different. Our environment, the things we ingest, and even travel can alter our cycles. Although an irregular period can sometimes signify something bigger such as pregnancy, menopause, or polycystic ovarian syndrome, these aren't always the case.
Every situation is different, but if you're feeling some differences in your monthly visitor, consider these 11 everyday things that can change your menstrual cycle before you start to freak out.
If you've been having a hard time right now, stress could be the cause of your messed up period. "Stress is the number-one contributor to a change in menstrual cycles because when you are stressed, your body shuts down the hormones you need to ovulate," says Dr. Carolyn Alexander, MD, F.A.C.O.G, of Southern California Reproductive Center over email.
A lot of different stressors can alter your cycle, Dr. Sherry Ross M.D., an OB/GYN, tells Bustle, from physical stress like a lot of exercise, to emotional stress. If you've gone through a breakup, are grieving somebody, or are experiencing a lot of emotional upheaval, your period may be delayed or disappear.
2. Other People's Cycles
Ever gotten your period at the same time as your roommate? It's no coincidence. Your cycle may be affected by other people's menstruation. "Co-workers often end up getting their periods around the same time as one another due to their pheromones, a secreted or excreted chemical factor that triggers a social response in members of the same species, especially those in close proximity," says Dr. Alexander.
The scientific jury is out on whether period syncing is the reality for most people. A study of Chinese students in 2006, a survey of users by period-tracking app Clue in 2017 and multiple studies in the 1990s have cast doubt on the idea. It may be a coincidence, or there could be other factors at work.
3. Too Much Exercise
If you have recently amped up your exercise routine, it may be to blame for your irregular cycle. "Excessive exercise can lead to skipping periods or light periods because your body needs a certain about of body fat to ovulate," says Dr. Alexander. Even if you haven't lost a lot of weight, Dr. Ross says, exercising to the point of excess can also increase stress on your body to the point where periods lighten or stop.
4. HIGH LEVELS OF Alcohol
Hitting up happy hour frequently can impact your hormone levels, but it's not clear whether a few drinks per week can make any real change to cycles. People with alcohol use disorder often experience issues with their menstruation. "Excessive alcohol or drug abuse can definitely affect your cycle," Dr. Ross says.
Both prescription and nonprescription medication can change your menstrual cycle, even something as simple as Advil or Motrin. "Medication including the birth control pill, steroids, thyroid medications, and antipsychotics can affect your period," Dr. Ross says. The birth control pill often creates an artificial bleed every four weeks or so, though it's entirely possible to forgo that entirely. Thyroid medication, antipsychotics and other medications can alter the way the body regulates menstrual cycles and hormone levels.
6. Your Diet
A changing diet can also have an effect on your period. Both eating too much and too little can change the rest of your body's functions, including your menstrual cycle, so if you've been trying out a new diet or haven't been eating your best, it could result in an irregular period. The body may decide that you're not capable of sustaining a healthy pregnancy right now. "Sudden weight gain or loss can affect your period," Dr. Ross says.
7. Certain Beauty Products
"Cosmetics and beauty products can contribute to a change in your period cycle," says Dr. Alexander. This is because some products contain chemicals that are considered endocrine disruptors, which means they impact your hormonal health. This includes certain hair dyes, moisturizers, and even shampoo. It's important to note that the research about endocrine disruptors has largely been conducted using very large doses on animals, so there's no cut-and-dried link between their use in beauty products and your own cycle.
8. An Inconsistent Work Schedule
Working longer than normal or at off hours can impact more than just your mood — it can affect your period as well. A study published in Epidemiology in 2011 found that women who had very inconsistent work schedules — defined as 20 or more months of shifts rotating from day to night — were more likely to have very short cycles or very long ones than women who have a set work schedule.
If you're a smoker and have been experiencing more painful PMS symptoms, it may be due to the cigarettes. A study published in Tobacco Control in 2016 found that women who smoke are more likely to have painful menstruation than women who are non-smokers. It's not known why this might be, but it's a link worth keeping in mind.
10. Your Thyroid Health
"Longer menstrual periods with a heavier flow and more cramps can be a sign of hypothyroidism, where thyroid hormones are in short supply," says Dr. Alexander. The thyroid regulates a lot of bodily activities, including menstruation, and a malfunctioning thyroid can create issues with your cycle, as it may slow it down.
Staying up late or not getting adequate sleep can affect your hormones, which can have an impact on your ovulation and menstruation. Poor sleep can also impact your melatonin levels, which play a part in regulating your menstrual cycle.
"Your menstrual cycle is an amazing barometer of your overall health and wellness," Dr. Ross says. Keeping track of your periods can help you keep track of your health, but if you see any major changes, be sure to consult with your doctor.
Dr. Sherry Ross M.D., OB/GYN
Dr. Carolyn Alexander, MD, F.A.C.O.G.
Lawson, C.C., Whelan, E.A., Lividoti Hibert, E.N., Spiegelman, D., Schernhammer, E.S., Rich-Edwards, J.W. (2011) Rotating shift work and menstrual cycle characteristics. Epidemiology. 22(3), 305-12. doi: 10.1097/EDE.0b013e3182130016.
Liu, Y. Gold, E.B., Lasley, B.L., Johnson, W.O. (2004) Factors Affecting Menstrual Cycle Characteristics, American Journal of Epidemiology. 160 (2) 131–140. https://doi.org/10.1093/aje/kwh188
Ju. H., Jones, M., Mishra, G.D. (2016) Smoking and trajectories of dysmenorrhoea among young Australian women. Tobacco Control. 25, 195-202.
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