While humans have come a long way in terms of assistive reproductive technology, when it comes to sex, we’re still mixed up on myth vs. reality. Case in point: the idea that changes in how you eat or fuck can affect the sex of the offspring that you (or any livestock you may be tending) conceive. Ancient Greeks and Romans believed that tying the right testicle of a ram would produce female rams, while tying the left produced males. Hindus thought that sex on odd-numbered nights would yield daughters. Aristotle claimed you could have a boy if you had sex when north winds were blowing.
Some of these myths persist to this day, even though now they’re dressed up in some science. Websites like How to Conceive a Boy Naturally and Babble are mostly geared toward women, advising them to eat red meat for a boy, or have sex on the exact day of ovulation for a girl. Parenting.com advices women who want a girl to avoid orgasming during sex (contractions will favor the smaller, boy sperm, they say.) For ladies who do want a boy, the site suggests drinking cough syrup before sex: The active ingredient will make cervical fluid more “slippery,” giving boy sperm a leg up. Then there are the optimal positions: Have sex standing up to have a boy, or in any position that promotes deeper penetration.
Technology offers some more reliable approaches, including prediagnostic genetic diagnosis (PGD) and sperm sorting, both of which work in conjunction with in vitro fertilization. PGD is meant to screen embryos for genetic disorders, but reveals the sex in the process. Parents can then implant only the embryos with the sex of their choice during IVF. Sperm sorting uses laser, dye or centrifugation to isolate sperm by sex, before implanting the right ones into an egg. A third, more controversial method some use is to discover the gender via ultrasound, and, if it doesn’t align with their wishes, abort. (In the U.S., the House rejected a bill to ban sex-selective abortions in 2012.)
The first two methods are, unsurprisingly, prohibitively expensive for people who aren’t Chrissy Teigen, who admitted that she and John Legend used the technique to ensure they had a daughter. Price tags for a cycle of IVF treatment that includes PGD average around $18,000, but the cost can easily double or triple as multiple rounds of treatments are often required. And even when IVF treatments are covered, most plans won’t cover PGD. One couple told the New York Post they spent $100,000 to have a girl after having two sons. It took seven rounds of IVF because of a miscarriage and their initial embryos turning out to be male. (Not even PGD is perfect.)
If you don’t have shitloads of money, is there anything you can actually do to guarantee a boy or a girl? “The short answer is no,” Dr. Dudley Danoff, a urologist at Cedars Sinai and author of the The Ultimate Guide to Male Sexual Health, told MEL. “There’s really no way you can manipulate sperm to create the child gender of your choice. I think there’s a lot of people out there selling snake oil and offering all kinds of remedies and tricks, and 50 percent of the time, they’re right. So if you’re batting 500, that’s pretty good in the Major Leagues.”
Danoff says he certainly understands that people have preferences when it comes to the gender of their child. “I see patients who say, ‘I have three girls and I’m trying for a boy,’ and then the next year they will come in for a vasectomy because they had another girl.”
And he’s heard all the myths about how to game the reproductive system, everything from sleeping on the right side to sex “under a full moon on Tuesday,” but “none of it stands up to the scrutiny of scientific explanation.” There’s no evidence that “good swimmers are boys, or bad swimmers are girls,” he adds. “But it sounds great, and you could make a nice story about it.” When his patients express a gender preference, they usually realize nothing much can be done in this arena — unless they’re getting IVF.
Fertility clinics, at the very least, can isolate the gendered sperm or embryo you’re after, and go from there. There are no official statistics on the success rates, though the clinics themselves claim as much as 100 percent success rate on PGD procedures. That’s misleading, because any number of things can go wrong for the same reasons in vitro fertilization fails: damaged embryos, chromosomally abnormal embryos, high maternal age, miscarriage and more. And those success rates can’t tell us how many times it takes to stick.
“It’s all enormously profitable,” Danoff says. “Sperm implantation, IVF, sorting, but each time you do it, it could cost $15,000 or $10,000, and many times it fails.” In other words, just because you can accurately screen an embryo for sex doesn’t mean you can be sure to become pregnant by that embryo to term.
Which is why his advice for anyone hoping for a boy or girl, unless they have a lot of money to spend on something with no real guarantees, is pretty simple.
“Roll the dice,” he says. “Love your partner. Have good thoughts. And a good glass of red wine.”