Actually, I found reading this somewhat uncomfortable.
I'm not actually sure what the author is saying, but it sounds like some variety of "don't try to figure out the sex of your unborn child because they might be trans and then you'd be wrong."
Huh?
* Is she implying that knowing the sex beforehand somehow increases the pressure on a child to conform to gender norms? If so, sounds like a stretch.
* Is she implying that the lives of transgender people are made easier when our parents don't know our sex before birth? That would be total poppycock. The child would still need to go through the discovery phase, make a decision about transitioning, decide which of two one-way paths to take, and face certain societal disappointment (at best) about their choice.
* But most of all, I'm really tired of people making token (but onerous) demands on the cisgender world in my name. I DON'T want the cisgender world to change itself to accommodate me. I don't MIND people having expectations of children based on their gender, because the vast majority of the times those expectations materialize as expected. Yes our society needs to be more supportive of those who are different, both in gender and in every other way. Denying oneself the knowledge of the baby's sex will not make that happen, just as learning the baby's sex won't prevent that.