While browsing Andrew's blog and looking to see all of the posts that I missed (I'm pretty sure I haven't looked at the instructor blog more than once this semester), I saw his post about the behavior problems in class. While the comment on the wall about semen on a pregnancy test and skewed the results was very crude and inappropriate, it got me thinking. Could that actually happen?
The first step I took in finding this answer was to look at the science behind a pregnancy test. How does it work?
As this website explains, both types of pregnancy tests test for a hormone called hCG or human chorionic gonadotropin, whether in the blood or in the urine. Higher levels of this hormone indicate pregnancy.
So does semen have this hormone?
News Medical says it does not. Semen is composed mainly of sperm, fructose, and other enzymes. If you're curious, the full list of what makes up semen can be found here.
Obviously, semen then cannot skew the results of a pregnancy test. But now I am even more curious: What causes those false positives? What can cause elevated levels of hCG other than pregnancy?
JustMommies.com has an interesting article on this very subject. Certain medications, for example, contain hCG as it is useful for fertility conditions. Also, if you have a medical problem (like certain cancers, for example), your hCG levels may be elevated from that. And perhaps the most interesting, one that piques my curiosity even more, is that if there is too much protein in your urine, the test could also come up possible.
I haven't been able to find much information on this, so maybe you guys can. Is there any definitive explanation for as to why protein will show on a pregnancy test as elevated hCG levels? Also, given these abilities for a false positive, should you trust an at-home pregnancy test or just go to the doctors?