Period 17: does hormonal contraception reduce the risk of endometriosis?
Book news
Just a few quick notes about the book – if you aren’t tired of hearing me talk about the book, and my research more broadly, I’m on This Podcast Will Kill You this week as well as On Health: A Podcast for Women.
I also had my first book event at The Literary Book Bar, here in Champaign, Illinois. Dr. Toby Beauchamp was such a kind and thoughtful and brilliant interlocutor, and I enjoyed the questions I got from the audience! Now I just need to figure out how to have something clever to write in books when I sign them.
My next in person books are coming up soon – May 8th in Seattle, Washington at Town Hall Seattle with Angela Garbes, and May 9th in Portland, Oregon at Science on Tap. If any of you live nearby I hope you’ll come – make sure to introduce yourself!
Links
Wesley Lowery writes powerfully of the problems with false impartiality in journalism, past and present, in “A Test of the News” for Columbia Journalism Review.
“Unthinking reliance on unnamed government sources was at the heart of the failure to provide accurate facts during the run-up to the Iraq War, and still drives credulous coverage of law enforcement. We focus on politics and perception, not the messy details of policy. Right-wing complaints about hagiographic coverage of liberals and unfair treatment of conservatives echo Lippmann’s critique that too often the press hunts for facts to support a preconceived narrative.
While mainstream journalism codified its political independence, it never liberated itself from the constraints of American capitalism. Our press remains first a business, whose interests often clash fundamentally with its values.”
Meredith Wadman covers the story of David Gilbert, an NIH-funded researcher known to have committed sexual harassment, as he moved institutions and kept his funding… even though the NIH knew what he did. As she writes in Science Magazine,
“NIH learned the full nature and extent of his misconduct at FSU before making the new award but after his move to San Diego—where his behavior elicited a new probe, Science has learned, and drove at least one woman scientist from the institute.”
And finally, because I still don’t want long COVID, I bring you a story by Charles Schmidt in Scientific American about the problem with repeat infections – which many seem to have accepted as a new normal instead of, I don’t know, making some effort at mitigation and testing.
“A team of researchers led by Ziyad Al-Aly, a clinical epidemiologist at Washington University, in St. Louis, and his colleagues concluded that reinfected people are twice as likely to die and three times as likely to be hospitalized with COVID than those infected only once, regardless of their vaccination status. Al-Aly’s team reviewed data from nearly half a million COVID patients treated by the U.S. Department of Veterans Affairs (VA) between March 2020 and April 2022. Among them, roughly 10 percent had been infected with SARS-CoV-2 between two and four times. Some patients continued to have symptoms during the six months of follow-up, Al-Aly says, and the severity of a patient’s disease typically worsened with each new COVID episode.”
Click on through to read the full thing!
Weird period fact
I’ve had a few people write in when they subscribe that they’d like me to cover endometriosis, so here’s my first weird period fact on the topic! (Did you know that when you respond to this newsletter you do in fact respond directly to me? Feel free to ask me questions and I’d be happy to answer them here!)
It is often assumed that oral contraceptives are protective against endometriosis. But there are a few hints that the relationship is not as meaningful as we’ve previously thought, OR that the risk is dependent on other factors. For one, the association between oral contraceptives and risk of endo is probably affected by the fact that oral contraceptives can suppress some endo symptoms, effectively kicking the can down the road until the moment when that person may need to go off of them. So it’s not reducing risk, it is instead masking the symptom and leading to delayed diagnosis.
Then there is the fact that there appears to be a difference in this relationship depending on parity (whether or not you’ve birthed a kid). In a prospective sample from the Australian Longitudinal Study on Women’s Health, study authors found that oral contraceptive use was associated with an increased risk of endo later in life, among those who did not have kids. Among those who did have kids, the prior oral contraceptive use was protective.
I wrote about this for my book, so I took a quick look at the literature to see if there had been any other publications on this in the last year or two that I’d missed. The only one I could find that I hadn’t read before was from 2004, looking at a sample from the Nurses’ Health Study II, also a prospective cohort. This study looked at oral contraceptive use but ended up taking it out of their model because it did not affect the results – meaning, being on contraceptives or not did not affect one’s potential for getting endo.
tldr: Oral contraceptives do not reduce risk of endo, except perhaps among people who birth children, and if anything it may mask symptoms in young people using it which can delay diagnosis and treatment later. That doesn’t mean don’t use it if you need it or want it! It just means if you have a family history maybe talk to your doctor in case they recommend testing.
Sources: Missmer SA, Hankinson SE, Spiegelman D, Barbieri RL, Marshall LM, Hunter DJ. Incidence of laparoscopically confirmed endometriosis by demographic, anthropometric, and lifestyle factors. Am J Epidemiol. 2004 Oct 15;160(8):784-96. doi: 10.1093/aje/kwh275. PMID: 15466501.
Tu, F. F., et al., The influence of prior oral contraceptive use on risk of endometriosis is conditional on parity, Fertility and sterility, 2014. 101(6): 1697–704.
Vercellini, P., et al., Oral contraceptives and risk of endometriosis: A systematic review and meta-analysis, Human Reproduction Update, 2010. 17(2): 159–70.