The Crazy-Making Sophistication of At-Home Pregnancy Tests

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Before home pregnancy tests, people relied on a variety of arcane methodologies to determine whether or not they were pregnant. One of the more memorable is the so-called “rabbit test,” wherein the urine of the suspected pregnant person was injected into a rabbit. The popular shorthand claimed that a pregnant woman’s pee would kill the rabbit, which is not exactly how it worked — the rabbit had to be dissected before the test could be performed. Either way, the rabbit died.

Given its antecedents, modern home pregnancy tests have thus rightly been celebrated as a boon. Home pregnancy tests — which were developed by a graphic designer only recently credited for her work — analyze urine for human chorionic gonadotropin, or hCG, a hormone produced as soon as a fertilized egg attaches to the lining of a uterus. Depending on when one ovulates, this initial attachment takes place roughly a week or so before a regular period would occur. If the egg can burrow in and get comfortable, hCG levels will typically double every 48 to 72 hours over the first few days, making a positive pregnancy test ever more likely as the days go by. (HCG is detected with greater accuracy in blood, but this option is not available over the counter.)

Currently, thanks to capitalism, people in industrialized nations have access to a bewildering array of different tests, all making confident claims. This bounty has given rise to a new ailment of modernity: the pee-stick fugue state.

Here’s how that goes, if you are hoping to become pregnant: You look at the calendar. You go to Walgreens. You pick the largest, pinkest, most expensive box, which promises results long before you miss your period. You part with $22, plus tax, and take it home. There are three sticks. You pee on the first. You wait three minutes. You look at the stick. On first glance, there’s nothing there. But because you want to be sure, you look closer. Behold! An extremely thin line is discernible. You look at it in every available light. You go online and read about the difference between true positives and “evap lines” (shadowy and possibly apocryphal lines left by drying pee on certain brands of test), and look at pictures of other people’s sticks. You pee on another stick. Again, the faintest of lines. Your spouse comes home. “I’m pregnant,” you say. “Sort of.”

The next day, you pee on the remaining stick. You place the new stick next to yesterday’s sticks. The line is there, as faint as ever. You buy more tests. You end up with four different brands, two of which say that you are pregnant, two of which don’t. You take one apart and inspect its innards. You set up a home lab on the dining-room table, your various sticks marked with Sharpie noting the date and time of the pee. Sick of pee splashing around your bathroom, you start peeing in a cup and dipping the stick therein. If it gets really bad, you make your spouse, who is — in my case — biologically incapable of becoming pregnant, pee in a cup and dip a stick in that pee as a control (negative). You call your health-care provider, who tells you to wait a week. Four days later, your period comes. Or maybe it doesn’t! Maybe the lines on the sticks get darker and darker, and all the brands fall in an affirmative line, and then you are pregnant. Either way, you discover you have spent your week’s grocery budget on pregnancy tests (either way, the rabbit dies).

I’ve been through a few rounds of this fugue state, the most recent of which resulted in a pregnancy that appears to be going as it should. I have had a baby before; logically, I am familiar with the mechanics and uncertainties of the early days. But still, I entered the fugue state. My husband found the array of sticks and results bewildering, and while I provided him with belabored explanations of hCG levels and test sensitivities and the stages of implantation, I sometimes suspect he blamed the incongruities on user error. We laughed about my “hysterical pregnancies,” until I decided it wasn’t permissible for him to make this joke. Sometimes I would leave the room abruptly. “Where you are going?” he’d ask. “I’m visiting my sticks,” I would say, and spend five private minutes holding them up to the light.

The only ready analogue for the fugue state I can find is sexual madness; the thing where you conceive a sudden, violent passion for someone that, when it passes and you are left surveying whatever wreckage it wrought, seems inconceivable, if not insane. But this is actually an unjust analogue. The pee-stick fugue state is more complicated, a combination of a tantalizing amount of imperfect information; a certain degree of corporate obfuscation; an uncertain universe; and a connection between physical state, material circumstances, and future outcomes that is, I think, unique to pregnancy. There is so little you can know about pregnancy, even when the sticks give you the news you want.

If you are a stalwart and practical person with good impulse control, perhaps this isn’t a relatable scenario. But the internet is where people like me find a sisterhood of the anxious possibly-pregnant, and a massive collective folklore has developed up around the mysteries of the home pregnancy test. There are many charts that allege to record the true sensitivities of various tests (most of these charts disagree with one another), and there are entire galleries of stick photos uploaded by people looking for a second opinion. There are even apps that will invert the coloration of a photo of a pregnancy test, so as to more clearly show a line that is basically invisible to the naked eye (a practice called “tweaking”).

These forums are a poignant artifact. For one, they show how biology is in some respects a great equalizer. Or not an equalizer, exactly, since the outcomes of pregnancies vary wildly according to individual and economic circumstances. (The disparities in health-care systems come into relief, on the boards: British women always seem to be headed in to have “their bloods done” in a medical office; American women scheme about where to buy the cheapest tests in bulk.)

The vocal participants in the forums are people who are anxious to become pregnant, but many possibly-pregnant people don’t want to be pregnant at all, and it’s fair to assume they are lurking. The fugue state can be motivated by dread as much as by anticipation; the window to obtain an abortion is narrow and legislatively shrinking. The need to know is universal, whether someone is desperate for their first baby, their tenth, or to head off reproduction at the pass.

Sometimes the boards demonstrate that we don’t know what we are talking about. “A digital is more accurate” seems to circulate as an accepted piece of wisdom, not because of any particular test’s stated sensitivity, but because it has a screen that gives a definitive “yes” or “no.” (Pregnancy-test manufacturers have exploited this fallacy, as well as the anxiety of early testing: A Clearblue ad features a faintly positive pink-dye test alongside a Clearblue digital with a screen reading “Pregnant.” “Get a clear answer when you need it most,” the tagline instructs.) Another cheery piece of conventional wisdom: “Any line, no matter how faint, is a positive.” And this one is true, more or less. If there is enough hCG to show up in a test, regardless of its sensitivity, you are most likely pregnant, at least for the moment. So-called “chemical pregnancies,” or very early miscarriages, wherein the fertilized egg attaches to the lining of the uterus but can’t hang on and burrow in, are now easy to detect.

The Cadillac of tests, and the main culprit for the increased awareness of early miscarriage, is the First Response Early Result (the “FRER”), which advertises itself as “the ONLY brand that can tell you 6 days sooner than your missed period” (the FDA vets these statements in the U.S.; other early-test brands can claim to deliver a positive one day later). The FRER has detected an hCG level as low as 6.3 mIU/mL — 5 and under is understood to be “not pregnant,” and my health-care provider will not call a blood test positive if the hCG level is below 25. This is to say, the FRER is catching women who are pregnant in the most theoretical sense.

Doctors and sensible people will say, “If you don’t test early, you won’t have this problem.” But capitalism is the Garden of Eden, and home pregnancy tests are the Tree of Knowledge. The FRER allows you to track every near miss in your uterus, or to discern the beginnings of the greatest sea change of your life. For a price — the more you pee, the more money someone makes.

One of the reasons it took so long to develop the home pregnancy test is that doctors — who were almost entirely men — didn’t think that women could be trusted with the sensitive information of pregnancy even when the technology became available in the 1960s. Viewed against the backdrop of history, peeing on sticks and sharing informal scholarship about their inner workings is a reclamation of knowledge once denied. Likewise, entering the fugue state — visiting your sticks, trying not to head out to the drugstore to buy another box — may make you feel sheepish, as though you are confirming every dire prediction about women’s ability to handle the facts. But I want to tell you that many factors have conspired to put you in this state. I want to tell you it’s not stupid to need to know. I want to tell you that you aren’t out of your mind. Also, that you aren’t alone.

The Crazy-Making Sophistication of At-Home Pregnancy Tests