Will a COVID-19 Vaccine Throw Your Period Off?

Find out what could cause any irregularities from an Ob/Gyn
covid vaccine and your menstrual cycle

After being vaccinated against COVID-19, many people have reported unusual symptoms like swollen lymph nodes, “COVID arm” and blood clots. Understandably, these symptoms can be quite startling and concerning since many of us have never experienced them before. Some of the side effects reported are believed to be associated with your body’s immune response to the vaccine. But what about the reports of altered menstrual cycles after vaccination?  

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While women across the country have noticed changes in their periods shortly after vaccination, there currently is no concrete evidence that COVID-19 vaccines can have a direct effect on women’s menstrual cycles. Instead, these changes may be associated with the body’s response to stress.   

Ob/Gyn George Fyffe, MD, FACOG shares his insights about why this is happening and gives some helpful tips to help women manage the effects of stress.   

How menstrual cycles can be affected by your immune system  

We might not realize that there’s a connection between the uterus and the immune system, but there is one. Dr. Fyffe says that as a woman is about to ovulate, her immune system ramps itself up to prevent any infectious agents from interfering with the fertilization and implantation of the egg. Once the egg is fertilized and implants, the immune system dampens to accept the pregnancy.  

Dr. Fyffe adds that the lining of the uterus also has immune cells, and those cells can be affected by hormonal changes. Uterine infections can also cause changes in a woman’s normal menstrual cycle. 

“The hypothalamus in the brain is the hormonal control center that works in conjunction with the anterior pituitary gland. Together, messages in the form of hormones are sent to the ovaries and the uterus to increase or decrease hormone levels to facilitate ovulation, pregnancy and the return of the menstrual cycle if fertilization doesn’t occur. Emotional stress, physical stress, and chemical stress may affect the hormonal control center which can result in menstrual cycle changes.”  

What is chemical stress?  

Chemical stress applies to medications that can alter your period.   

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“Women who are taking medications for seizure disorders, diabetes, thyroid conditions, hypertension, depression or other conditions might notice irregularities with their menstrual cycles. These medications can interfere with the hormones that are responsible for menstruation. Some may even cause loss of menstruation,” says Dr. Fyffe.   

What if you experience period changes after being vaccinated for COVID-19?  

Your healthcare provider can determine the best way to manage the disruption in your menstrual cycle. Dr. Fyffe says that it’s good to discuss any changes with your healthcare provider because they’ll be aware of what’s going on and you can work together to determine the best course of action. 

“Shared decision making between the provider and the patient will aid in determining and managing your body’s hormonal changes.” 

How cortisol can affect your period  

According to Dr. Fyffe, stress can increase your cortisol levels. Too much cortisol can lead to inflammation as well as a variety of physical and mental health issues.   

Chronic stress can affect your body’s normal cortisol production rhythm. An overabundance of cortisol can affect your metabolism, which can lead to obesity. It can also lead to sleep disturbances as well as changes in menstruation.   

What women can do to stay healthy right now  

According to Dr. Fyffe, three things that may promote health are exercise, rest and a healthy diet. 

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Exercise provides many benefits for your body. It can help your body manage blood sugar and insulin levels, it can help with weight management, it reduces your risk for heart disease and improves your mental health and well-being. Dr. Fyffe adds that in addition to stress, the pandemic has caused more of us to adopt a sedentary lifestyle. So by increasing exercise, you can lessen the effects of stress on the body.  

Get enough sleep  

While everyone has different schedules and obligations, Dr. Fyffe recommends getting seven to eight hours of sleep a night. Sleep disturbances and/or inadequate periods of rest, can affect your hormones and subsequently, your menstrual cycle.    

Watch your diet  

“Aim for a balanced diet which should include adequate levels of carbohydrates, proteins, low-fat, low-sugar, and iron-rich foods. And remember that when you eat too much or don’t eat enough, it can affect your menstrual cycle. Also, make sure that you’re drinking enough water. The recommended daily amount of water is 64 fluid ounces.” 

Take note of the stressors around you

Dr. Fyffe says a lot of factors in our environment can add to our stress. These things can influence our diet, sleep schedule, and medication regimen.  

“Do you have a child or a parent who’s sick, or are you getting home late at night and not sleeping well? All of that can significantly affect your menstrual cycle. Just the idea of being so busy, not eating well, not getting enough sleep — all those things can affect your brain. Another thing to think about is that we’re social animals. Before the pandemic, we all had routines. On the weekends, you would go see the people you care about.

“The pandemic took a lot of those social interactions away. So, when a lot of the things that we used to take for granted were taken from us, we probably didn’t realize the impact that it would have on our minds and bodies.” 

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