Things They Should Invent: quick and easy general fertility test

There are all kinds of ways to test if you're fertile (i.e. ovulating) today, and there's a lot of medical science that diagnoses specific problems that may cause infertility. But we could also use a quick and easy pee-on-a-stick type of test to give you a rough idea of how fertile you are in general compared with the average woman. It doesn't have to diagnose the reason behind any reduced fertility it finds, just the presence or absence (or, ideally, the degree) of fertility.

For example, I put a lot of time and energy and resources into not becoming pregnant. But I don't actually know if I'm fertile. I've never been pregnant, so there is room for the possibility that I cannot become pregnant. I'd really like if there was an easy way to confirm that I am in fact fertile before I go through any invasive and time-consuming sterilization procedures.

This isn't just applicable to the childfree. People who want children could do a quick general test for the presence of fertility to decide how much time they want to spend on "trying" or whether to go with adoption or artificial conception. People could take the test every year to see if (or how much) their fertility is declining as they age, and plan their lives accordingly. If you want to impress upon teens the importance of responsible sexual behaviour, you could have them take the test and see just how must of a risk they'd be taking. People who have recently had babies could see when their fertility returns and make their family planning decisions accordingly.