When Period Pain Is Bad Enough to Keep Her Out of School

"Every month she misses a day or two of school. She says the painkiller only helps at the time."

This is what I hear from parents who bring in a middle or high school daughter. There is no fever and nothing turns up in the tests, yet for those few days the child can do nothing.

Let me start with where this pain comes from. It is not a vague pain but a pain whose place and sequence have been established.

A substance the uterus makes itself squeezes the uterus

During a period, as the lining inside the uterus comes away, a substance called prostaglandin is released. This substance makes the muscle of the uterus squeeze. Since squeezing is needed to push out what has come away, that in itself is something the body has to do.

The problem is the degree. When a lot of this substance is made, the squeezing force becomes strong and lasts a long time. When the muscle squeezes hard, the blood vessels passing through it are pressed as well. The place where blood flow has been reduced ends up short of oxygen, and the metabolites released in that state make the nerve endings that feel pain sensitive.

It squeezes → blood flow drops → that place becomes painful. This is why period pain comes as a wringing sensation. It resembles the structure of a muscle cramp.

That painkillers work well is the evidence for this explanation

The painkillers commonly used block the making of that substance itself. Rather than merely masking the pain signal, they work on reducing the production of the causative substance.

So they work well. According to the material, about 80% see an effect with drugs of this class. This is more so when they are taken timed to around when the pain is starting, rather than after it has started.

There is no need to hold out against the medicine. I do not quarrel with painkillers. Whether the child can go to school that day comes first. That said, if the state is one of having to lean on that medicine alone every month, it also means there is something left to look at ahead of it.

There is a reason warmth makes it better, too

That warming the belly helps is an old saying, and why that is follows directly from the explanation above.

Heat loosens the muscles of the belly and increases blood flow around the pelvis. If squeezing and the resulting drop in blood flow is the axis of the pain, this amounts to touching the opposite side of it. What has gathered and stagnated and what has constricted in the vessels come loose together.

Exercise sits in a similar place. It is not something to do while in pain — there is material showing that the intensity of the pain decreased when it was done steadily over several weeks.

So what I look at

Rather than the side of masking the pain, I look at that point where blood flow decreases.

I ask whether the hands and feet are usually cold, whether the lower belly is always cold and uncomfortable when pressed, whether the body swells before the period, when the pain starts, and how long it lasts after taking a painkiller. Even with the same period pain, a child in whom the squeezing side stands out and a child in whom sluggish circulation stands out are different.

And at this age sleep and meals are often unsettled. A body whose reserves have been shaved down feels the same pain more strongly. So I do not look at the period pain on its own, but look at the state of the whole month along with it.

When to see an OB-GYN first

If the period pain started newly a good while later rather than around menarche, or gets noticeably worse year by year, or there is pain outside the period as well, or a painkiller taken properly barely works at all, or the flow is excessively heavy — it is better to be seen by an OB-GYN first. There are cases where there is a separate cause, and that has to be looked at there.

Primary dysmenorrhea usually begins within one to two years after menarche. If the point at which it started falls outside that frame, it is better to have it checked once.

I would not want a child collapsing for a few days every month to be passed over as a matter of course. There is a reason it hurts, and that reason is usually in a place that can be worked on.

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Sources

• A summary that the cause of period pain is an increase in prostaglandin in the uterine lining, and that about 80% see an effect with production inhibitors — Asan Medical Center Disease Encyclopedia
• A review summarizing that ischemia caused by uterine contraction pressing on blood vessels makes pain nerves sensitive, and that heat and exercise help — Journal of Pain Research, 2024

Written by Dr. Heo Ji-young (Ph.D. in Korean Medicine Pathology, Kyung Hee University · former Research Professor of Herbology, Kyung Hee University)