Through 7 episodes, the abortion one is my least favorite, but it's still fine. It's just more South Park than BoJack. There's something gleeful about the abortion jokes that brings Matt and Trey to mind. On the other hand, there's a reasonably nuanced message in there as well and it never comes across as overly preachy, which is also like the best South Park episodes.
I'm just left feeling like the episode is a bit of a waste by the end because it doesn't add much to the season's arc, nor does it really build on the characters. In general, I find their episodes about social issues (Prickly-Muffin, Chickens) to be solid but seldom favorites because they're lighter and lack the emotional devastation of the more personal episodes. And this one right here is a funny little topical episode, but everything else so far has tapped into what the show does best. This has been a great season, but something has to be the low point.
By the way, I find it very interesting and admirable that they put an episode extolling the virtues of parenthood and a highly pro-choice episode so close together. That was a bold choice.