When are you more likely to get sick during your monthly cycle?

When are you more likely to get sick during your monthly cycle?


There are a variety of reasons your immune system can weaken, making you more likely to fall ill with a head cold, sore throat, lung infection or other illness–for example, it can happen when you’re run down, experiencing lots of stress or getting too little sleep.

Well, there’s also a specific time in your monthly cycle when your immune system falters, putting you at greater risk of getting a viral or bacterial infection. It’s during the end of your Week 2 when you’re ovulating.

Antibiotic use spikes after ovulation

One method that researchers recently used to establish this was to examine how much medication women used across their menstrual cycle.

In a study published in the journal Pharmacoepidemiology and Drug Safety, they reported finding that antibiotic use peaked during the second half of the study participants’ cycles–with a steep rise at the end of their Week 3 (around Day 22 in a 28-day cycle), which is when progesterone is highest.

This means that the women in the study who had fallen ill contracted their infection about a week before and the symptoms had built up enough for them to head to the doctor to get it checked out–making the end of their Week 2 the apparent time when their immune system was unable to fend off a virus or bacteria, allowing the infection to take hold.

What kind of illnesses are common after ovulation?

The study participants who used antibiotics said they did so for cold or flu symptoms, sinus infections, strep throat or sore throat, urinary tract infections, vaginal bacterial infection, upper respiratory infection and mononucleosis (a virus that causes severe flu-like symptoms).

It’s important to keep in mind that while the women in this study reporting using antibiotics for a variety of viruses that cause cold and flu, antibiotics actually don’t help you get over viruses any faster. They are used to treat bacterial infections (such as strep throat and bacterial pneumonia). However, some doctors may still give you antibiotics for a virus if you request them because they don’t want to deal with the hassle of explaining why a course of antibiotics won’t make you better. Unfortunately, repeated use of antibiotics when they’re unnecessary can make you resistant to their beneficial effects, which can then make it more difficult for them to heal you when you really need them.

Why does your immune system weaken at ovulation?

This isn’t the first study to pinpoint end of your Week 2–the ovulation phase–as a time when your immune system weakens. But, it adds to the growing evidence that shows you’re more vulnerable to viruses and bacterial infections at this time.

So, why does your immune system weaken at ovulation? Researchers theorize that high estrogen triggers this drop in immunity to help prevent the body from attacking sperm during this fertile phase as a way to increase your chance of pregnancy.

At the same time, on these cycle days peaking estrogen is pushing you to be more daring and less concerned with your health–so you may take more risks than usual, for instance, going to crowded parties at the height of cold and flu season or touching an ATM or shopping cart handle (two common sources of germs) without washing your hands or applying antibacterial gel afterward.

As a result, this double-whammy of less illness-fighting protection and taking more risks with your health can set you up for spending a week or two battling an annoying illness.

How can you avoid getting sick during ovulation?

Sure, you know you should be washing your hands, eating healthy foods, sleeping regularly and avoiding stress all cycle long to keep your immune system strong. But, now that you know your immune system naturally weakens during the end of your Week 2, make a point to take more precautions leading up to and including these cycle days, for instance, by carrying antibacterial gel with you, cleaning cuts thoroughly and steering clear of coughers and sneezers.

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