Seems like that would work. You just have to collect CM for your cervix and then put it on the test strip. Also you have to test your CM at your fertile time when it's EWCM, cause any other time would give you a more acidic number and irrelevant anyway as the sperm doesn't need to survive outside of the fertile window. Another way to do this, but costs more, is called a PCT or post-coidal test. Basically, you BD the night before and then the next morning about 10 or so hours later they get some of your CM and check if his sperm are still alive and swimming and they check your pH at the same time. I had it do e cause I was also concerned about that.