Can You Buy Stock In Pregnancy Tests?

I have to admit, I'm a planner. So my husband and I planned on having kids 2 years after we were married and then we gave ourselves an extra year when he switched jobs. Then, keeping true with my personality, I planned on seeing a positive on my pregnancy test, and when I didn't get it, I planned on seeing it the next day. Every month, I'd run out and buy 2 boxes of pregnancy tests. I needed 2 boxes because I'd run out before the month was over. My husband (he's not as much of a planner as I am) never questioned why I needed to test 6 times to know for sure that I wasn't pregnant. I thank him for that. In the first few months I didn't think much of it when the tests showed a negative. Sure it was disappointing, but I figured it would take about 3 months for my body to adjust and get ready for a baby.