Cats are also induced ovulators which compounds their ability to produce several litters per year.2 (zoetisus.com)
It's also possible that if you have always had it easy when conceiving before, you are a good ovulator and hence have a better chance than women who struggle to get pregnant. (checkpregnancy.com)
Cats are spontaneous ovulators, which means that eggs or ova are only released from the ovaries if a cat when it is mated. (cat-health-guide.org)