The latest app being downloaded by young women looking to get laid isn’t an upgraded Tinder or rehashed Hinge. It’s a new form of contraception.

Here’s how it works: Natural Cycles sends you a thermometer in the mail that you use to measure your basal body temperature first thing in the morning. Your temperature changes during the menstrual cycle and can be used to detect ovulation and identify your fertile—and infertile—windows. So, after logging your temperature into the app each day for roughly three months, the app’s algorithm gives you either a helpful green day (go ahead and raw dog it) or a red day (wrap up that sausage).

Natural Cycles, which charges users $89.99 per year, claims to be 93 percent effective and is the first F.D.A.-cleared and European Commission–marked birth-control app. It’s also incredibly popular on both sides of the Atlantic. The app currently has more than 1.5 million users, registered across 162 countries.

But there are a number of reasons why I would personally avoid the app like I would a man with his hand suspiciously deep in his pocket on the subway.

First of all, you have to take your temperature as soon as you wake up, and that time has to be more or less the same every day. Not only that, but if you get up to pee in the middle of the night or snooze your alarm in the morning, it can mess with the readings.

There are a number of reasons why I would personally avoid the Natural Cycles app like I would a man with his hand suspiciously deep in his pocket on the subway.

Plus, you can’t trust the temperature taken on any day you’re sick (O.K., fine), or when you have a hangover (S.O.S.). While the algorithm can manage with a couple of skipped days—the app recommends registering five days a week to ensure you don’t get overrun with “red days”—I’m not sure I can promise it any.

The timing of all this is bizarre. At a moment when we’re declining cookies and worrying about data breaches, many women will happily let an app rummage around their cervix in the name of baby-free sex. (Natural Cycles has said it does not share or sell users’ data.)

Then there’s the Roe v. Wade rollback. If there were ever a time when young women who do not want babies should be extra careful with birth control, you’d think now would be it.

To take or not to take?

The skepticism regarding Natural Cycles is warranted. There have been many reports of people getting pregnant off the back of apps like this one, so much so that in 2018 the company was reported to Swedish authorities after nearly 40 women using the app sought abortions at a single Stockholm clinic. This checks out—a 93 percent effectiveness still leaves room for 7 women in every 100 to have a womb stowaway, a number that multiplies when you have millions of users.

But here’s the thing: I totally get it.

Use of the pill is decreasing in most places. In 1973, a third of American women were on the pill, down to 22 percent in 2017. I had to come off the pill because the side effects were too strong. For at least one day a month, I felt uncontrollably sad, sobbing so hard I couldn’t breathe and waking up the next day with my eyes as swollen as Kylie Jenner’s lips. Many of my friends, the majority of whom have been on some sort of hormonal birth control since puberty, feel the same way.

Of course, most women take the pill and feel totally fine. But the side effects are being talked about more. Call Her Daddy’s Alex Cooper has a whole bit on decreased libido, a side effect of some contraceptive pills, in a recent podcast episode. And a YouTube video made by model Hailey Bieber in which she partially attributes a stroke she had to her birth control has gone viral since its April release.

Condoms, too, are decreasing every year. (The C.D.C. has reported that, from 2007 to 2017, their use fell among U.S. high-school students from 62 to 54 percent.) There are a number of possible reasons for this. S.T.D.’s feel less life-shattering than in previous generations, more boys are having issues with erectile dysfunction, and sex ed is seriously lacking in many schools.

But probably the biggest reason, as any woman will tell you, is that men just don’t like using them. The comedian Taylor Tomlinson put it best when she compared trying to convince a man to wear a condom to trying to convince a toddler to put a coat on over his Halloween costume “No! You’re gonna ruin it!” Many women have mentioned to me that they have resorted to the pullout method instead, a sex-ed red flag if there ever was one, and a drain on the wallet when you have to buy pregnancy tests every week.

If there were ever a time when young women who do not want babies should be extra careful with birth control, you’d think now would be it.

There are other contraceptive options available to women; I.U.D.’s, for example, which have recently increased in popularity (from 2 to 14 percent from 2002 to 2017). They work well for a lot of women—once they’re in.

Friends of mine who have had I.U.D.’s implanted agree it was the worst pain they’ve ever experienced. It’s a procedure that I am confident would happen under proper anesthesia if it involved putting literally anything up a man’s urethra.

Last year, the British journalist Caitlin Moran tweeted about her own experience, reporting that she’d fainted twice from the pain and that all the doctor had offered her was a Lucozade when what she wanted was an epidural, considering they were “opening [her] cervix and inserting a doll’s coat hanger!”

A friend of mine experienced agony so bad after her I.U.D. insertion that what should have been a 5-minute walk took her more than 40. After having it removed, she now uses Natural Cycles. “For me it’s a good alternative to hormonal contraception,” she said. “I couldn’t find anything else that worked for me.”

Because that’s the issue. All the options are awful, and women are left to pick the least bad one. When it was introduced, the pill was a revolutionary, life-altering invention for women. It still is. But times have changed, and we deserve more. The fact that so many women are turning to an app that asks you to give up boozy nights out and sleeping in and still risk a surprise pregnancy should terrify us.

They’re currently in the process of trialing a pill for men, but researchers worry men won’t want to take it due to the side effects, which for decades they have relied on women to endure.

If a male version of the pill is successfully launched, every man better start crushing them into their morning shakes before I personally start campaigning for the rollout of forced (reversible) vasectomies. When it comes to the side effects of safe sex, we should be doing better by women and not expect them to continue to just groan and bear it.

Flora Gill is a London-based writer