I was recently reading a particularly smutty novel wherein the protagonists were relying on the old standard "pull and pray" method of birth control. As the scene continued, the method became less "pull" and more "pray." But how much sperm does it take to get pregnant? Does it need to be a full load, or will just a little dab do ya — and your egg? Pulling and praying seems like a smart idea if it takes a lot of sperm to get pregnant, right?
As it turns out, it doesn't take as much sperm as you might think to knock you up. “A fertile male typically ejaculates 2-5 ml of semen, and each ml contains about 100 million sperm,” Dr. Kecia Gaither, MD, MPH, FACOG, double board-certified in OB/GYN and Maternal Fetal Medicine and Director of Perinatal Services at NYC Health + Hospitals/Lincoln tells Romper.
The reason for so many swimmers? Well, it’s to ensure that at least one of them makes it to the golden egg — literally. “So many sperm are required because some sperm are shaped funny, some don’t propel themselves well, or the acidic vagina kills them,” Dr. Kim Langdon, MD, an OB/GYN, tells Romper. “The cervical mucus can trap the sperm, causing them to die very fast.” After all, those sperm don't have GPS— just a very excited dude shoving them in the general direction of home and evolution needed to allow for the millions who end up losing their way. And if they don't get lost? They die trying, Dr. Barry Witt, MD, a board-certified reproductive endocrinologist and Medical Director with WINFertility explains to Romper. “Those that enter the cervix or uterus likely disintegrate or are ultimately expelled with fluid discharge or with subsequent menstrual flow,” says Dr. Witt. Because a woman's vagina is designed to beat off foreign invaders with more vigor than finesse.
According to Dr. Gaither, getting knocked up is a one-sperm job. “It only takes one sperm to fertilize an egg, and the pregnancy begins,” she says. In fact, it doesn't have to be that much, or even ejaculated directly into your vagina. Just having your man ejaculate on or around your vulva can apparently lead to pregnancy, too. I distinctly remember asking my tenth grade BFF how much sperm it takes to get pregnant, and she told me a little was OK. (She was definitely wrong.) “Pregnancy is always POSSIBLE if sperm are in or around the vagina, particularly if a small amount enters,” says Dr. Gaither. Good to know for all the pray and pullers.
And it’s not absolutely impossible to get yourself pregnant, either. How? Well, if you’re giving your guy a hand job, and you touch your girly parts with those semen-laden fingers, there’s a super slight (yet possible) chance you could become pregnant. “In most cases, sperm must be deposited in the vagina where it comes into contact with cervical mucus and then swims up to the fallopian in order to fertilize an egg and result in a pregnancy,” Dr. Witt explains. “However, sperm can be present in pre-ejaculate fluid, so in couples using the ‘withdrawal method’ of contraception, pregnancy can occur with ejaculation outside of the vagina because the pre-ejaculate may contain sperm.”
I am choosing not to think about how many times third base may have almost knocked me up. But according to the BBC, sperm are more likely to die than reproduce, and thank the sweet heavens for that, because I made some interesting choices in my late teens. If you want to get pregnant, just know that there's no such thing as too much of a good thing. Good luck, and those sperm will just keep swimming until they get to their goal, which is a positive pregnancy test.
Dr. Kecia Gaither, MD, MPH, FACOG, double board-certified in OB/GYN and Maternal Fetal Medicine, Director of Perinatal Services at NYC Health + Hospitals/Lincoln
Dr. Kim Langdon, MD, an ob/gyn
Dr. Barry Witt, MD, a board-certified reproductive endocrinologist and Medical Director with WINFertility
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