According to WebMD, PCOS causes a woman’s body to produce higher-than-normal levels of androgens. These are hormones that are usually thought of as male hormones, because men have much higher levels of androgens than women.
Androgens are important in the development of male sex organs and other male traits.
In women, androgens are usually converted into the hormone estrogen.
High levels of androgens interfere with the development of your eggs and the regular release of your eggs. This process is called ovulation.
If a healthy egg isn’t released, it can’t be fertilized by sperm, meaning you can’t get pregnant
I hope this answers your question.
SOURCE: https://www.webmd.com/infertility-and-reproduction/polycystic-ovary-syndrome-fertility#1