I was trying to schedule a sonogram last year when my understanding of a basic scientific principle was totally upended. The nurse, attempting to discern how pregnant I might be, turned out to be utterly uninterested in the date of conception. She only wanted to know the date of my last period. That, she explained, is how pregnancy is calculated. Which meant that as far as the medical community was concerned, I was technically five weeks along, even though there was no way I could physically be more than three. Those two previous weeks, I guess I was . . . pre-pregnant? Pregnant-in-waiting? Truly, this was stunning news.

So last week, when John Becker, a lawmaker from Ohio, casually suggested that an ectopic pregnancy could be “removed from the fallopian tube and reinserted in the uterus” (nope: tragically, that procedure doesn’t exist), and when prominent pundit Ben Shapiro confidently conflated the concept of “six weeks of pregnancy” with “a six-week-old embryo” (two different things, actually), and when Georgia Gov. Brian Kemp signed a bill requiring that abortions may only take place in a time frame before many women even realize they’re pregnant — when all of those things occurred, my frustration approached a cosmic level. Not toward those lawmakers, but toward the squeamish cloak of secrecy and ignorance that shrouds all things ovarian.

We are collectively terrible at talking about reproduction. Especially when it comes to pregnant bodies. We’ve got to do better.

When the Georgia abortion bill was signed into law, I heard some armchair OB/GYNs claim that a woman could easily meet this six-week deadline by simply taking a pregnancy test really, really early — like, immediately after sexual intercourse! — to find out whether she had an unwanted pregnancy to terminate.

Dispiritingly, these advice-givers did not seem to know that fertilized eggs take several days to implant in the uterus. And that pregnancy tests are not highly accurate until a period has been missed. And that, even assuming one has a textbook 28-day menstruation cycle — many are longer or far less predictable — a period won’t be missed until at least 15 or 16 days after conception.

Harry and Meghan, the Duke and Duchess of Sussex, debuted their newborn son this week, and I saw royal-watchers sharing the family photo, innocently wondering why Meghan still looked “fat.” Clearly, they’d never learned that the female body doesn’t bounce back like a rubber ball; it can take weeks or months or never for midsections to return to their previous size.

Some of the pontificators in these instances were male, but far from all of them. These aren’t the infractions of individual men. This is centuries’ worth of an attitude that, though conception might be a biological miracle, it’s also a gross one, filled with pudge and sludge that — la la la la la! — decent people are allowed to run screaming from. Plenty of folks are willing to treat fetuses as precious citizens, but seem to regard the bodies that nurture them as embarrassing slums. At a party, I once saw a new father proudly call his new kid a “princess” and his wife a “champ,” but then showily cover his ears when the wife mentioned the word “placenta.” As if the placenta wasn’t precisely what had allowed Princess to thrive.

And everyone at the party laughed! As if this willful ignorance was acceptable! Because it is, in fact, acceptable: We have accepted it.

Stories like this used to seem amusing. I have snickered over BuzzFeed listicles with titles such as “24 Ridiculous Things People Have Actually Believed About Periods.” I once snorted at my desk while skimming a complaint from a gentleman annoyed that menstruating women felt the need to waste money on sanitary products. Why didn’t they just learn to “hold it,” he suggested, the way men kept themselves from urinating?

But I’m beginning to realize that this kind of ignorance isn’t something to be laughed off. Because if we’re going to make laws around biology — about whether tampons should be taxed, or whether abortions should happen by six or eight or 14 weeks — we need to understand that biology. Because whether you’re an abortion rights advocate or antiabortion, you should be able to understand and defend the complexity of your position.

There’s another reason that has nothing to do with the law: If you don’t understand how female bodies work, you might end up believing some really harmful things about women.

If you think that menstruating women need sanitary products only because they’re unwilling to “hold in” their periods, then you might end up believing they’re just lazier than men.

If you view postpartum women as “fat,” then you might be inclined to see women as slightly less disciplined. If you don’t know what a placenta does, you might start to think your wife’s body is just gross.

If you think a woman should know she’s pregnant within days — as opposed to the weeks that biology generally dictates — then you might assume that not knowing within days is a sign that she’s scatterbrained and irresponsible. You might decide she’s unable to manage her own health.

We desperately, desperately need to do better at talking honestly and openly about reproduction. About missed periods, and heartbeats, and fetal-growth charts, and menstruation cycles, and fertilization timelines, and all of it.

Because if defending your position requires relying on falsehoods, then perhaps you should be questioning whether it’s defensible at all.

Monica Hesse is a Washington Post columnist writing about gender and its impact on society.

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