Talking about birth control can be a very sensitive topic, and in most cases, isn't something you dive into upon first meeting someone (unless you're immediately planning to have sex).
There are so many different kinds of birth control, and when it comes to the options for women, there are a myriad of side effects (many of which are inconvenient) that can crop up. Some women opt out of hormonal birth control altogether due to how it affects their bodies, while others swear by the pill. Plus, IUDs, the patch, Nuvarings and good old fashion condoms all present plenty of hormonal and non-hormonal options to comb through, so the conversation about contraception is vast and complex.
Not to mention, the expectation that women bear the brunt of birth control opens up a whole different bag of issues including burdensome gendered expectations, the institutionalized misogny in the health care industry, and the ways (some) men are conditioned to view pregnancy as a women's issue and not a two person event.