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Last year, Lacy Phillips had covid-19 for a couple of weeks from late October to mid-November. Initially, she was infected while she was on her period.

“It was unusually heavy and included just massive clots,” the writer and podcaster in Jeffersonville, Ind., tweeted a few months later. “Pretty sure I passed a clot that was basically a cast of the inside of my uterus.”

It was so extreme she took a picture. Then Phillips, who was 38 at the time, didn’t get a period for two months. No spotting, despite having her usual PMS symptoms of cramps and constipation.

In January, she had her first period since she had covid; again, she said, it was heavy and accompanied by an unusual amount of clotting. Then she got the Pfizer vaccine in March and April, and skipped another cycle.

Anecdotal reports are starting to emerge about the coronavirus vaccines potentially disrupting women’s menstrual cycles. But how much the disease itself affects women’s periods has also not been covered widely.

“I thought it was strange that a study got initiated to investigate the effects of the vaccine, but I never heard about any official studies about the virus,” Phillips told The Lily.

It’s hard to know exactly what caused Phillips’s irregular periods. She also has a thyroid and autoimmune condition, so she’s not certain what role those play, but like many women, she is curious about why more research hasn’t been done regarding issues key to women’s health.

“We know that covid can cause cellular level changes, inflammatory changes in every organ system. So why wouldn’t we talk about the effects that covid, the infection, could have on the reproductive system?” said Jane van Dis, an OB/GYN in Los Angeles and the medical director at the women’s health network Maven Clinic. “We have every reason to think that women who have covid infections might experience inflammatory changes or responses in the endometrium in the lining of the uterus that could affect their period.”

In September 2020, a study of 237 women in Wuhan, China, was published to examine if the SARS-CoV-2 infection had an effect on menstruation, sex hormones and ovarian reserves of women who contracted the disease.

Upon examining the menstrual data of 177 female patients, researchers found that “45 (25 percent) patients presented with menstrual volume changes, and 50 (28 percent) patients had menstrual cycle changes, mainly a decreased volume (20 percent) and a prolonged cycle (19 percent). The average sex hormone and AMH concentrations of women of childbearing age with COVID-19 were not different from those of age-matched controls.”

The authors concluded that “the menstruation changes of these patients might be the consequence of transient sex hormone changes caused by suppression of ovarian function that quickly resume after recovery.”

Covid-19 is a new virus, and the effects are still being studied. Nevertheless, women’s menstrual cycles are not often accounted for in research.

As van Dis points out, in the initial coronavirus vaccine studies, researchers didn’t collect menstrual health data when they were studying the effects of the vaccine.

“Everyone was shocked and surprised to hear that the vaccine might have a short-term limited effect on the menstrual cycle,” said van Dis, who is also the co-founder at health-care consultancy Equity Quotient. “Then everyone said, in retrospect, why weren’t we asking?”

Van Dis continued: “As a gynecologist, menstrual health is a vital sign — it tells us about the thyroid, it tells us about the functioning of the ovaries, it could tell us about the functioning of the pituitary. We need more women in these bigger studies, especially affecting population health — to be asking the right questions up front.”

Aside from the increased overall stress or changes to routines that all of us are feeling in the pandemic, which can disrupt periods, there are other biological issues at play, according to Shruthi Mahalingaiah, a physician specializing in ovulation disorders, reproductive endocrinology and infertility at the Massachusetts General Hospital.

“There are two aspects of menstruation to consider in relation to either illness or vaccine. The first is the reproductive endocrine system — including the signaling loops between the hypothalamus, pituitary and ovaries,” she said. “This signaling allows for ovulation which leads to menstruation in the setting of declining hormone levels in the absence of a fertilized egg.”

Stress about the illness or the vaccine can affect this signaling, resulting in periods with different lengths or skipped altogether, she said.

“The second aspect is the actual process of endometrial lining shedding. It is not known whether or how either the infection or vaccine may alter the menstrual bleeding — heaviness of flow, duration or pattern of bleeding,” Mahalingaiah said, emphasizing the need for more research on the effects of both the illness and the vaccine on women. “We need to understand whether the covid-19 infection specifically alters the process of menstruation, bleeding lengths or heaviness, or development of the endometrial lining.”

Concerns about covid’s effects on menses looms large for many of the women who are long-haulers, founders of online groups say.

“There are tons of women who have noted significant changes to their menstrual cycles, including both absences and irregularities in their menses,” said Amy Watson, the founder and head administrator of the Long Haul COVID Fighters Facebook groups, which have a combined 12,600 members. “Many women have reported having much heavier periods with heavy clotting. There are women who’ve gone into early menopause, and women who were perimenopausal prior to covid, but who have had perpetual periods for months now. The one thing that seems super consistent is that long covid has massively messed up women’s gynecological health.”

The same hormonal disruptions are often discussed in another Facebook group devoted to long-haul covid, Survivor Corps, which has 167,000 members.

Watson herself had a total hysterectomy one year and eight months before contracting covid, but she still has one ovary.

“I’m still ovulating and am subjected to monthly shifts in the intensity and severity of my [long covid] symptoms. Women in our groups consistently report experiencing a worsening of symptoms — what they call a “relapse” — when they have their periods,” she said.

For van Dis, the topic opens up the bigger issue of why women’s health issues don’t play a larger part in all of the conversations about covid or public health in general.

As she put it: “The manner by which society interacts with female reproductive systems, whether it’s periods or whether it’s pregnancy, has got to change. This is a point where we have not evolved. And obviously in a pandemic, it has life-and-death consequences.”

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