You're very pregnant and are ready not to be. Your partner comes in and says, "I heard giving oral sex induces labor." It sounds good to you, but as you're thinking about receiving oral sex, you realize your partner meant you would be the one giving oral sex. But can swallowing semen induce labor, or is your partner just angling for some oral action?
This is a very scientific question to which the internet has provided a surfeit of non-scientific responses. In fact, a little Googling will send you into a spinning wild zone of positions needed to properly swallow, how swallowing semen definitely works, the amount of semen you need to get the job done, and even some handy (mouthy) infographics. There's an overwhelming amount of oral encouragement out there, my friends.
So what is the reasoning behind it? Is it something in your partner's penis? The motions? Magical sexual magic that hails from the beginning of time blessed by Rowena Ravenclaw on the fourth night of the babymoon? It turns out that people are assuming that the same thing in semen that purportedly induces labor with sex, will do the same when taken orally. I'm calling this the oral versus suppository theory. If it works as one, it must work as the other, right? The proponents of this method argue that the prostaglandins found in semen can soften the cervix (via the esophagus?) and bring on baby, noted the Cleveland Clinic.
As it turns out, there's a small, but very important flaw in this idea. The prostaglandins found in semen, the very thing that horny forum writers the world over are telling desperate pregnant women will soften their cervix if they just swallow it like a pill, is meant to be applied topically to the cervix via sexual intercourse, not oral intercourse, according to the American Pregnancy Association. The cervix needs a direct hit of the hormone to be effective. However, apparently if you are pregnant and having an ulcer flare-up, swallowing semen may help in that area, but that's up to you. As far as the answer goes to "does swallowing semen induce labor?" It's just another anecdotal pipe dream. I'm not telling you not to try it, though, if that's what you're into. But do it because you want to, not because you think it'll make your baby come out.