In May 2014, “Daysy” hit the market. Daysy is an under-the-tongue thermometer that measures your basal body temperature, which is your body’s temperature when fully at rest, that may increase during ovulation. Basal body temperature is used by people who engage in cycle syncing or the rhythm method, a form of contraception/pregnancy planning where unprotected sex is either avoided or intentionally engaged in during the days immediately before ovulation.
Coming in at a price point of $330, Daysy claimed to be 99.4% effective at predicting fertility. And when an article was published in Mar. 2018 in the journal “Reproductive Health” supporting the company’s claim, the product seemed to be a groundbreaking new method to be considered. After all, Daysy’s manufacturer was comparing the product to intrauterine devices (IUDs), the most reliable form of contraception available, with failure rates measuring in at as low as 0.2%.
But just months later, in June 2018, renowned reproductive health scientist Dr. Chelsea Polis published a commentary in the same journal, outlining her serious concerns with the study’s research methods, specifically its survey-style data collection. “Reproductive Health” ultimately agreed with Dr. Polis, retracting the article in May of 2019. Although Valley Electronics has acknowledged the study’s retraction, as of Jan. 11, 2026, the company still claims the 99.4% effectiveness rate on its website. To contrast, medical institutions agree that basal body temperature tracking has an effectiveness rate of about 75% when used as a standalone method, with failures mostly due to measurement error and natural levels of fluctuation in hormonal cycles.
Birth control misinformation is widespread and varied. Internet influencers tell you about rare possible side effects, but without the context of just how rare they are. General users joke about the size of the warning sheet with their hormonal birth control pill, without knowing or saying that U.S. Food and Drug Administration regulations require all known, possible side effects to be listed. Conservative Christian groups perpetuate the false idea that Plan B is the same thing as an abortion pill, as one portion of their fight against women’s bodily autonomy. Contraceptive pills were a major milestone in the fight for bodily autonomy, and yet, 36% of American adults mistakenly believe emergency contraceptives and abortion pills are the same. 73% of American adults believe an emergency contraceptive can end a pregnancy in early stages, which is a medical impossibility because emergency contraceptives work by suppressing ovulation in the five days after being taken. Right-wing, ideologically motivated individuals spread the unscientific, culturally-charged claim that birth control changes your attraction, making you more attracted to men who present in a more feminine manner. Through it all, the voices of actual medical professionals are drowned out, and their message with it: if you are experiencing issues from your birth control symptoms, talk to your provider. Between the variety of schedules and methods, it is entirely possible to find a birth control option with minimal to no side effects.
Birth control is, fundamentally, a medication. Like all medications, side effects are possible, and it is impossible to predict with certainty what side effects you will experience until you take the medication. If healthcare providers could wave a magic wand and know exactly what symptoms a patient will experience, without the patient ever needing to experience those side effects, I am confident providers would do exactly that.
I won’t tell you that I’ve never believed false things about birth control. The prolific nature of this kind of misinformation, aided by rising conservative sentiments that are also potent online (see: clean girl and trad-wife content), spares none. In fact, up until recently, the little information I knew about birth control had steered me away from it entirely. But, as I have learned more, I have become increasingly aware of the casual misinformation that permeates every casual conversation about birth control and contraceptives. So, for a moment, let’s be very clear about how birth control works.
Hormonal birth control prevents the ovaries from releasing an egg via one of a variety of available hormonal combinations. The pill also thickens cervical mucus, which aids in blocking sperm from entering the uterus, and can thin the uterine lining, which decreases the chance of egg implantation in the uterine wall. Studies that account for missed or forgotten pills tell us that hormonal birth control is about 93% effective. 25% of women ages fifteen to forty-four in the U.S. use this method of contraception. Intrauterine Devices (IUDs), another common kind of birth control, are implants that thicken cervical mucus and, via the copper they are made of, interfere with the movement of sperm. Alternatively, they can be hormonal and operate in the same manner as the pill. They can be left in for three to 10 years, depending on the manufacturer, and have a 99% practical effectiveness rate.
The pill and IUDs are the most commonly used kinds of contraceptives. In comparison, the practical effectiveness rates of other birth control methods are lower: such as the cervical cap after giving birth (71%), the pull-out method (78%), the birth control sponge after giving birth (78%), internal condoms (79%), spermicide (79%), the diaphragm (83%), the birth control sponge before giving birth (86%), the cervical cap before giving birth (86%), external condoms (87%), the vaginal ring (93%), the birth control patch (93%), and the birth control shot (96%).
Finally, and very importantly, hormonal birth control methods do not affect your future fertility — except injectables, which can prevent ovulation for up to 18 months after the last dose, but do not have effects past that time period.
The it-girl, pilates princess, wellness influencer on your timeline (no shame, I keep up with a couple myself) who stopped taking her birth control to feel more grounded in her body, is not wrong for making that choice. But she is also not a medical provider, let alone your medical provider. And she certainly is not you. Take her advice on slickback bun tutorials and first-date outfits, not personal medical decisions. If you want to seek assistance with contraception here on campus, Student Health and Counseling has many resources available on campus, and can assist in attaining off-campus services as well. Contraception is not shameful, wrong, immoral, unhealthy or unsafe.
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