It makes me irrationally annoyed when I read femslash fanfic that has it where two cisgendered women having sex leads to pregnancy and then their child is a BOY. Not because, ewww, boys have cooties! But because science! Cisgendered women have XX chromosome which in humans only leads to other women. XY chromosome possessed by men is what makes it able for the fetus to develop into the male sex. You need the Y chromosome to have a boy and if two women having sex somehow leads to a kid then they don't have the correct chromosomes between them to have a boy since they're both XX and XX chromosomes can only reproduce other XX chromosomes or, you know, another girl.
I know, I know, f-preg is sci-fi! It's not real. Or wait,
they've already done it in Japan with two female mice and guess what? They only had girls. So yeah. Science. lol. I don't know why it bothers me so much but it does. I don't read much f-preg fanfic but whenever I do and the kid ends up a boy I usually click out. I guess I can only suspend my disbelief so much?
ETA: Using my Janeway frowny face icon because it's awesome and hilarious not because I take this super seriously and it makes me frown that hard. I should do my sixth rewatch for all of Voyager again. I think it's been a year since I last did that.