Girls as young as 14 are missing school and suffering from decreased quality of life due to painful period symptoms. To help alleviate these symptoms, teens and adult women with PCOS, endometriosis, fibroids, cramps, and heavy bleeding are being prescribed the pill. The results showed that they chose the ones with a certain gene set that were very different from their own, making them genetically compatible. When this set of genes is too similar, the risk of pregnancy loss increases. Women who were on the pill in this study chose the t-shirts with genes that were very similar to their own, suggesting5 that the pill might alter odor preference and disrupt disassortative mating preferences.