Margaret Crane wasn’t a scientist, nor did she have a chemistry background; the company had brought her on to work on a new cosmetics line. But she went home inspired, and set to work developing a simplified version of the test. Her first attempts to design the device were unsuccessful, and she was frustrated. Then one day she sat at her desk looking absentmindedly at a stylish plastic box she used to hold paper clips. She realized the container was the perfect size to hold the components needed for the test. A few months later, she presented her kit—it resembled a toy chemical set—to Organon, and in 1969 the company applied for a patent in her name. Two years later, her home pregnancy test, named Predictor, went on the market in Canada, and then, after gaining FDA approval in 1976, in the United States. When it hit the shelves, the Predictor cost $10, the equivalent of about $50 today.

The home pregnancy test was one of the most revolutionary products of the twentieth century. Before Crane invented it, women had to go to their doctor’s office and wait two weeks or more to get their results. With the Predictor, women could find out if they were pregnant in as little as two hours, in the privacy of their own bathrooms. Today’s at-home pregnancy tests are the size of Popsicle sticks and deliver results within minutes, but they work on the same principle of detecting hCG, a hormone found in high concentrations in a pregnant woman’s urine.[*9]

“Unlike medical tests that reveal something otherwise unknowable about a body, a pregnancy test can only speed the delivery of information,” writes Cari Romm in an article about early home pregnancy tests in The Atlantic. “Regardless of who pees on what, a pregnancy has other, more obvious ways of making itself known with time. The home pregnancy test, then, wasn’t just about knowing; it was about taking charge, a sentiment that fit in nicely with the ethos of the time.” When the Predictor and a handful of other similar tests came to market, Our Bodies, Ourselves, the seminal book about women’s health and sexuality, was six years old and abortion had been legal in the United States for three. Early advertisements for home pregnancy tests emphasized what they offered beyond a yes/no pregnancy result: privacy, autonomy, knowledge of one’s body. A 1978 print ad for an at-home test called it “a private little revolution that any woman can easily buy at her drugstore.”

But, as Romm notes, not all of the doctors, who saw their authority being overthrown, were happy about a changing status quo. In an editorial published in The American Journal of Public Health in 1976, one physician argued against the use of home tests: “I feel that the reputations of both the commercial concerns and the profession of medical laboratory technology will suffer unless legislation is introduced to limit the use of such potentially dangerous kits.” In a note following the piece, the journal’s editors were firmly on the side of the tests: “Not everyone,” they wrote, “needs carpenters to hammer in their nails.”

—

At-home pregnancy tests are now ubiquitous, and other private little revolutions have joined their ranks. In addition to testing their pregnancy status, women can now also test their fertility from the comfort of their couch. Understanding your fertility hormones now, the thinking goes, gives you more options later. Several online companies and fertility clinics now offer ways to do diagnostic fertility testing at home. The tests, taken via a blood sample, work by checking the levels of hormones associated with egg production and ovulation. I mentioned FSH and LH earlier, two of the hormones that concern fertility. Let’s recap those and get into a few more:

Anti-Müllerian hormone, or AMH, is secreted by the small follicles found in a woman’s ovaries. The level of AMH in the blood helps to approximate her egg supply.

Follicle-stimulating hormone, or FSH, is responsible for stimulating egg growth and starting ovulation.

Estradiol, or E2, a form of estrogen, is one of the primary hormones tied to ovulation and regular function of reproductive organs. Along with FSH, it offers clues on the state of a woman’s ovarian reserve, which is a fancy word for egg count.

Luteinizing hormone, or LH, is another key hormone responsible for ovulation. It also regulates the length of a woman’s cycle.

Thyroid-stimulating hormone, or TSH, regulates thyroid health. The thyroid plays a role in metabolism, heart function, the nervous system, and more, and affects things like ovulation, mood, weight, and energy.

Free thyroxine, or fT4, plays a role in thyroid health and is often tested alongside TSH.

Testosterone, or T, is, in women, secreted in small amounts by cells in the ovaries and contributes to ovarian health, bone health, mood, and libido. Recent research suggests it also plays a key role in which follicles develop, and are ultimately recruited, each month.

Prolactin, or PRL, stimulates milk production and pauses ovulation after a woman gives birth.

Having hormones tested by a reproductive endocrinologist at a fertility clinic can cost anywhere from $800 to $1,500. Products such as Modern Fertility’s kit—the company calls it “the most comprehensive fertility hormone test you can take at home to be proactive about your fertility”—retails at $179, as of this writing. The average Modern Fertility kit user is thirty-one, and after she does the at-home finger prick test and has up to eight hormones analyzed, she receives her clinician-reviewed customized report, which is based on her hormones, age, birth control, health survey, and latest research by physicians. She can then opt to have a one-on-one consultation with a fertility nurse (at no extra cost) to discuss her results.

It’s remarkable, really, that a few drops of blood can tell a person so much. Testing a woman’s hormones can help identify if there’s an imbalance that could get in the way of the ovaries releasing an egg, or that could be affecting more than just fertility; hormone imbalances can impact weight, sleep, and even generally how a person feels. The tests also shed light on what a woman’s timeline might look like—for example, if she could hit menopause earlier or later than average.[*10] And they offer clues with regard to egg freezing or IVF outcomes, such as if the user can expect to collect more or fewer eggs than average in these procedures.

I first spoke with Modern Fertility’s Afton Vechery in 2019. She and her co-founder, Carly Leahy, had started the company in Vechery’s apartment two years earlier. No one was talking about “proactive fertility.” But, Vechery said, “we were hell-bent on bringing this thing in the world because we believed with every ounce of our bodies that it was our right as women to have power over our reproductive future.” Modern society is much more focused on preventing pregnancy than on planning for it, and this was at the heart of what Modern Fertility hoped to change. They built Modern Fertility with a specific demographic in mind: people with ovaries who were not yet actively trying to conceive. A major part of the company’s message became: We don’t accept “wait and see” as an answer in any other part of our lives—and we won’t accept it with fertility. Like many other female femtech founders, Vechery and Leahy saw reproductive health as a mainstream wellness issue, something that can be tracked and monitored, much like how much sleep you get or how many steps you take.

How difficult it was to access and afford fertility hormone testing was another thing Vechery wanted to change. Most women don’t think to ask their primary care doctors or gynecologists about their ovarian health. When Vechery first tested her fertility hormones, she was billed $1,500 out of pocket and had to have multiple discussions with doctors to understand the results—a major one being that she had undiagnosed PCOS. Hearing Vechery’s frustrating tale about trying to get a full hormone assessment, I thought about a friend of mine who, when she was twenty-eight, was able to get a basic diagnostic fertility workup only after she lied to her gynecologist, saying she’d been trying to get pregnant for a year. Most insurance plans do not cover proactive fertility testing. Initial diagnostic testing sometimes is, depending on where you live and your health insurance plan, but qualifying for coverage often requires an infertility diagnosis. And to obtain that, couples generally have to prove to their doctor and insurance company that they’ve been trying to conceive for at least one year (more on this in chapter 9). Single women who are not currently trying to conceive but are trying to gain valuable insight into their fertility are usually out of luck.

Kindbody, a health and technology company that provides fertility, gynecology, and family-building care, is also in the business of DIY fertility. I’ll talk more about Kindbody in the following chapter, but in addition to its brick-and-mortar locations, the company has mobile clinics in several cities, where it invites potential clients to hop aboard a cushy, bright yellow van to have an exam and fertility testing done, sometimes for free.[*11] “Reproductive health is the only vertical of healthcare where you wait until something bad happens before taking any steps to correct it,” said Gina Bartasi, Kindbody’s founder and former CEO, in an interview. “It’s backwards. We’re here to change that.” In the same way a person doesn’t wait to have a heart attack to eat well or exercise, Bartasi wants to help consumers take more initiative in learning about their fertility. In 2022, the company began selling at-home fertility hormone tests for both women and men, in addition to other pre-conception, pregnancy, and postpartum products. The launch of Kind at Home, as the company’s consumer products division is called, is part of the company’s goal to be the single door for all fertility healthcare.

At-home or in-van fertility tests have their drawbacks. They can’t detect every type of hormone that plays a role in fertility, nor can they diagnose other health conditions that could be affecting a woman’s fertility. The tests often don’t account for women with irregular cycles. And for women on hormonal birth control—who are preventing pregnancy by manipulating their hormone levels, thus influencing their body’s usual levels—the tests can typically assess only two of the eight hormones I listed above: AMH and TSH. In any case, testing fertility hormones in isolation isn’t as helpful as actually looking at the ovaries and the number of follicles they contain, which renders the results of a fertility hormone test, particularly AMH and FSH levels, more useful and provides a fuller picture.[*12] During a transvaginal ultrasound, a fertility doctor counts the small resting follicles to see how many eggs a woman has waiting in the wings. The antral follicle count, or AFC, is a good predictor of a woman’s egg supply that month—known as ovarian reserve.[*13] Taken together, the ultrasound and the blood work are what’s known as ovarian reserve testing. It refers to the number of follicles in a woman’s ovaries and gives an indication of how her ovaries might respond when stimulated with hormone medications used in ART procedures.

Ovarian reserve is part of the overall picture of your fertility health; understanding it in context is important. Your age, lifestyle, and medical history are also important factors in determining how likely you are to get pregnant. Ovarian reserve testing is a standard component of an initial assessment at any fertility clinic because it provides a helpful baseline for anyone considering egg freezing or IVF; every egg freezer has her AMH and other fertility hormones tested and her ovaries examined in order to assess how she might respond to fertility medications. But for a woman who hasn’t yet tried to get pregnant and who is wondering about her current natural fertility, an AMH value isn’t all that helpful in that context. While a woman’s AMH level can help estimate the number of follicles she has inside her ovaries, it cannot determine exactly how many eggs she has or, crucially, what condition those eggs are in. It’s also not necessarily a good indication of when a woman ought to freeze her eggs. This is the biggest misconception concerning ovarian reserve and especially AMH testing: that it is a “female fertility test.” While ovarian reserve testing offers some valuable insight into a woman’s fertility and a sense of potential outcomes if she undergoes egg freezing or IVF—how many eggs her ovaries might yield when stimulated with fertility drugs—it is not an accurate predictor of a woman’s ability to conceive through sex now or at a specific point in the future. This crucial fact is missing from virtually all the hype around fertility testing.

A major 2017 study in The Journal of the American Medical Association (JAMA), the results of which were replicated in 2022, showed that AMH does not reveal a woman’s reproductive potential and that ovarian reserve tests are often useless for many of the women to whom they’re marketed, for the reason I’ve just given. The study, the largest to examine the impact of AMH and FSH levels on ability to conceive naturally, tracked 750 women ages thirty to forty-four with no history of infertility. The women, who were followed for a year, were tested for three common ovarian reserve biomarkers—AMH, FSH, and inhibin B[*14]—found in blood and urine. To their surprise, the researchers found that AMH levels were not significantly correlated with later pregnancy and birth. Women with a low AMH value or a high FSH reading—markers of diminished ovarian reserve (DOR), a condition in which the ovary loses its normal reproductive potential, compromising fertility—didn’t differ from women with normal levels in their ability to conceive. In other words, women who didn’t have normal levels of the two primary hormones associated with fertility were not any less likely to get pregnant from intercourse and give birth than women with normal levels.

Lead author Dr. Anne Z. Steiner, the reproductive medicine specialist and OB/GYN professor mentioned earlier, told Vox in an article about the study: “These tests are great measures of ovarian reserve, how many eggs you have. But they don’t work to predict a woman’s reproductive potential.” Steiner and many in the medical community thought the tests would be a good predictor of a woman’s natural fertility, because in people using ART to conceive, hormone values like AMH and FSH, as I’ve said, often correlate with how well a woman will respond to fertility medications—how many eggs she’ll yield—and her likelihood of getting pregnant with IVF. But the JAMA study, and other similar trials in which researchers looked at AMH and FSH levels as a marker for predicting natural fertility, showed that’s not the case.

A low AMH and a high FSH do mean that it’s harder for a woman to conceive via ART. That’s because the chances of egg freezing or IVF leading to a baby are directly tied to the number of eggs a doctor retrieves, and a woman with a higher ovarian reserve is more likely to respond robustly to the hormone meds she takes during a fertility treatment cycle, producing more eggs than a woman with a lower ovarian reserve.[*15] But these tests are not all that useful for a woman who has yet to try to conceive naturally, because regardless of her AMH and FSH levels and AFC, if she’s having menstrual cycles she’ll naturally ovulate one egg per month. So, the chance of natural pregnancy depends directly and exclusively on the chance that that month’s egg is a healthy one—not on how many are left in the reserves for the future. In this case, quality trumps quantity. So for women wanting to get pregnant through sex, the only real way to test fertility is to try to conceive.

That’s rather unhelpful to women who have no interest in becoming pregnant now. And while one could argue that at-home fertility hormone tests are a waste of time and money for a woman not planning on using ART to get pregnant, these tests have proved worthwhile for plenty of women. Case in point: When she was twenty-nine, Caroline Lunny, a former contestant on The Bachelor and a former Miss Massachusetts USA, took the Modern Fertility hormone test, expecting to find she was, as she put it in a blog post, “fertile as hell.” Instead, she experienced a rude awakening when she discovered she had the AMH levels of someone who was about to go through menopause. She discussed the results with her doctor, as well as the fact that her mother had gone through menopause relatively young. Lunny went through nine rounds of egg freezing and ultimately put eleven eggs on ice.[*16] Requiring this many rounds was very likely a result of her low AMH, as the above study lays out, but Lunny is glad she pursued egg freezing and wishes she had taken the Modern Fertility test even sooner.

So while the tests aren’t a good predictor of a woman’s fertility or egg quality and are not intended to replace the more in-depth diagnostic testing conducted by a physician, some of the information they provide could be well worth knowing. Hormone levels can, for example, detect—though not diagnose—underlying conditions such as PCOS. And hormone imbalances in general, as I said earlier, can impact a lot more than fertility. If the at-home test returns an unexpected or abnormal test result, the user might be alerted to a problem they otherwise wouldn’t have known existed and then have a sense of urgency to see a doctor for a comprehensive fertility evaluation. A reproductive endocrinologist can investigate potential issues related to infertility, from ovulatory disorders to fallopian tube blockages, and look for structural problems with the uterus that could affect pregnancy, such as fibroids and polyps.

On the other hand, uncertain results without adequate interpretation can cause increased anxiety, and acting on the results—for example, rushing to freeze eggs after receiving a dreaded finding of diminished ovarian reserve—may be misguided. Too often, women get their “numbers” without a true analysis of what those numbers mean for them personally, or their fertility and family goals. It’s common, for example, for a woman to learn she has a low AMH level and be devastated, assuming this means she’s infertile. Low AMH likely does mean doctors would have a harder time retrieving a lot of eggs in an egg freezing cycle but, at least based on the information in the JAMA study, it seems those women should have no reason to assume they’ll have a harder-than-average time conceiving naturally.

As testing fertility hormones outside a physician’s office becomes more common, some doctors are becoming increasingly worried that women might be falsely alarmed by results outside the norm, particularly low AMH—when the reality is, as I’ve just explained, that they are very likely to go on to get pregnant naturally. It’s not hard to imagine a woman with slightly abnormal hormone levels being pressed into egg freezing out of concern that her fertility is falling off a cliff when, in fact, that might not be true. Companies like Modern Fertility are quick to acknowledge their kits as one tool in the fertility assessment toolbox as well as to encourage women who use their product to follow up with a doctor. Kindbody similarly acknowledges that AMH testing is only one tool used to help gauge fertility. But I find the free AMH testing offered at Kindbody’s pop-ups troubling because of its debatable usefulness and the fact that the company targets women in their twenties and early thirties.[*17] It’s also concerning because of motive. Kindbody’s end-to-end brand is built around the consumer, and the company has every incentive to play up AMH testing as a valid measure of fertility. A woman stops by a Kindbody van on her lunch break, gets her hormones tested, and learns a thing or two about ovaries and eggs she didn’t know before, and when Kindbody emails her her test results—whether they’re in the normal range or not—the company reminds her that a Kindbody clinic is just down the road in case she might now want to consider egg freezing.

—

So, using an at-home fertility test or having hormones analyzed in a van is fine, but not truly valuable on its own. Testing fertility hormone levels in a vacuum can be misleading, especially if the user is a healthy woman who merely wants insight into her current reproductive potential. It’s great that she wants to learn more, but it’s imperative that she also knows that the data points the tests provide, particularly AMH, are not markers of whether she can or cannot become pregnant and that ovarian reserve testing alone can’t estimate a woman’s chances of conception in a given month. What’s important is understanding what the tests are and are not measuring, as well as their limitations, and knowing if and when to see a doctor to follow up on the results.

Hormone levels are one important piece of the quite intricate fertility puzzle. An adequate supply of good eggs, healthy fallopian tubes, and receptivity of the uterus are other ones. At the end of the day, though, the most important factor in determining a woman’s fertility is—you guessed it—her age. As much as we may want at-home magic answers and a crystal ball telling us everything we want to know about our fertility, they don’t exist. On the bright side, though, is the fact that all this increased testing and knowledge means that more is being learned about the true complexity of human fertility—by women themselves.

The bottom line is that these at-home hormone tests can be a helpful starting point. When a nurse from Dr. Noyes’s office called me to tell me my AMH level, I’d written the number down in my notebook and circled it. When she didn’t offer any context, I scribbled a question mark next to it so I’d remember later to find out if the number was good or concerning—which going down this AMH and fertility hormone test rabbit hole helped me to do. It’s good for women to know that ovarian reserve screenings are available, but there’s a fine line between educating women about their reproductive life span and exploiting their fears about it, although many in the fertility industry won’t say as much. But now you know. If you’re well informed as to what the tests mean and their limitations, checking your hormones can add to your understanding of your fertility trajectory. Because both AMH levels and egg count gradually decrease, keeping tabs on hormone levels over time can offer some insight into how steep the decline of your fertility “hill” may be. Having inaccurate or incomplete information, however, can be more damaging than having no information at all.

Remy: Shots, Shots, and More Shots

Remy couldn’t remember ever being this eager for her period to start. It was late March, and the fertility medications sat in her fridge, just waiting to be opened. Most women freezing their eggs begin the hormone injections on the second or third day after menstrual bleeding starts. Any day now, she’d get her period and be able to start the regimen of fertility drugs. She’d also be able to stop taking the Pill. Some women are put on an oral contraceptive pill before undergoing egg freezing, which can help follicles grow at a more similar size and rate and give a woman and her doctor more control over the timing of her egg freezing cycle.[*18] Inclined toward most things that help a ship run tighter, Remy hadn’t minded taking the Pill to temporarily control her ovulation. She was just glad she hadn’t needed to change up her regular birth control method, a copper IUD, during the egg freezing process; it could stay right where it was for the retrieval.

Remy is the kind of person who always has a five-year plan of one kind or another, like the one that said this was the year she was going to start trying to get pregnant. That mindset—healthy habits, healthy pregnancy, healthy eggs, healthy baby—kept her motivated. She had been drinking green juice every day for three weeks, wanting to be in peak condition before beginning the shots. Breakfast as usual, every day: oatmeal with almond butter, blueberries, and dried cranberries. Weaning herself off coffee in anticipation of starting the injections had been rough. She’d gone from having several shots of espresso a day to three cups of coffee to a single cup. Baby steps. It was making her feel cranky, and she got a little depressed every time she thought about the toll the fertility medications might take on her body. She’d heard somewhere that by the end of all the days of shots, it would feel like she was carrying around a sack of potatoes.

But at least the process felt less daunting once she realized how structured it was. Remy took pride in putting on autopilot all the components of her life that could be managed that way. It was the giving up control of outcomes she wasn’t so good at; she didn’t like that it was hard to picture what her body was about to go through. As a second-year anesthesia resident, she had put IVs and epidurals in patients hundreds of times, but she didn’t particularly like sticking needles in herself. At the fertility clinic, when the nurses demonstrated how to prepare and administer the hormone shots, she’d become overwhelmed. The way the nurses did it wasn’t the way she would have done the injections—but she was the patient this time, not the doctor.

A few nights later, it was finally time to start. Remy went through her normal evening routine, doing more or less the same things she usually did. Since she had been on call at the hospital the night before, she slept all afternoon. When she woke up, she drove to her favorite trail and ran six miles listening to a podcast episode for company. It was sunny and cool, perfect weather for her last run for a while. Post-run smoothie back at home and then another walk, catching up with an out-of-state friend on the phone. Finally, a long shower with candles and donning her staple comfy clothes: Lululemon leggings and a tee. She sat at her kitchen table, damp hair wrapped in a towel atop her head, and opened the packaging.

The two cocktails on the hormone injections menu that night: Gonal-F—it came in a fancy pen, to be dialed up to the right amount—and Menopur. She reconstituted the medications, her anesthesiologist brain in full-focus mode. Her nerves were shaky; the anticipation had her feeling all jazzed up. She had resolved to do the hormone shots herself—it felt symbolically important somehow—but all of a sudden she wanted some company. At the last minute, she picked up her phone and FaceTimed Christina,[*19] her best friend. She needed a distraction and asked Christina to tell her a silly story. While Christina rambled on about a time her mother had all the shoes stolen out of her car, Remy pinched the skin around her lower stomach, let out a deep exhale, and plunged the needle in. It hurt a lot more than she expected. But she was psyched. Bring it on.

Skip Notes

*1 A few days before ovulation, cervical mucus is clear, heavy, and slippery—think raw egg whites. This consistency helps sperm swim up to meet an egg at ovulation.

*2 Technically speaking, you can take your temperature vaginally, orally, or rectally to chart your BBT. The books classically say to use an oral glass mercury thermometer immediately upon waking to get the most accurate reading. Digital oral thermometers work well, too, as long as they have the appropriate accuracy and precision.

*3 If you’re trying to get pregnant, the more often you have sex during this window, the better. Especially one or two days before you ovulate, because the egg starts to deteriorate quickly after it’s released from the ovary. Think of it like a sperm cell waiting in the wings, ready to greet the egg cell as soon as she emerges.

*4 They’re most effective when multiple FAMs are used together. Using FAMs perfectly correctly and consistently throughout the menstrual cycle, though, can be difficult to do. With typical use—using FAMs the way the average person does, which is sometimes incorrectly or inconsistently—pregnancy rates increase.

*5 I use Clue Plus, the paid version of Clue’s app, which gives access to many features and modes. As of this writing, it costs $10 per month or $40 per year; the price varies depending on the user’s region.

*6 These apps can also be quite useful for alerting the user to trouble with their cycle. Clue has a whole section, for example, for when one has recurring cramps and what that might represent. Or whether it’s normal to have a nine- or eleven-day period (which, again, helps close the information gap from our childhood).

*7 For women who are trying to conceive, fertility tracker apps can be a helpful tool, particularly when using the app to transition from preventing pregnancy. Also neat: Several fertility-tracking apps have a feature that lets users share their ovulation info and cycle monitoring with a partner or a friend.

*8 Explicitly asking users if they want to share their anonymized information is, obviously, the best practice here; Clue, for example, invites users to opt-in to doing so and “be part of closing the diagnosis gap for some of the most common yet most under-diagnosed and under-researched health conditions.”

*9 While hCG was identified in the 1920s, it wasn’t until the 1960s that scientists turned to immunoassays—tests that combined hCG, hCG antibodies, and urine—and discovered that if a woman was pregnant, the mixture would clump together in certain distinctive ways.

*10 The average age of menopause in the United States is fifty-one.

*11 Initially, the vans typically parked on high-traffic corners and were a marketing tool. Now they’re used in various communities to serve self-pay and privately insured patients, as well as employees of companies that Kindbody has contracted with; employees interested in using their Kindbody employee benefit can pop into the mobile clinic parked at their work campus during their workday to learn more and do initial testing.