That's really interesting. I think people would be surprised at how much medicine is not evidenced-based -- not because doctors are bad at science, but because gathering medical evidence is hard. Randomized controlled trials are the gold standard, but declaring "We're going to gather up a bunch of trans men who expect to become pregnant and randomly assigning them to continue testosterone or not" is going to be logistically challenging and ethically complex.<p>The point that women with PCOS are not given androgen blockers is fascinating. I wonder if anybody has tried that and observed anything.<p>In the absence of evidence, doctors are forced to muddle through. It sounds reasonable not to alter the hormones when the body is doing something where the body is already setting up a specific hormone mix, even if imperfectly. But that's just caution in the face of ignorance, not a factual statement.