It was never spelled out explicitly, but it seemed to me she might have man parts :) In any case something that prevented her from getting children and that was visible to a doctor from superficial examination.
A transgender wouldn't have a uterus, which the robot doctor confirms she has near the beginning. She also doesn't have "man parts", since the mammogram confirmed her breasts were real, and the dildo-looking probe went in with no problems. People really need to pay attention when watching a movie.
Very simple. An accident that causes scarring on the uterus can prevent the placenta from attaching properly when pregnant. That would make it nearly impossible to carry a baby to term.
Wow, people are really wacked out sometimes. There was absolutely NOTHING in this film that even hinted at her being transgender or anything other than just infertile for some reason. I guess the assumptions were based on the fact that Liv's character made such a big deal about keeping it a secret. That's how people were with this kind of information in the 70's. (that's right kiddies, people didn't reveal all their innermost secrets on Facebook every day). And what does "visible to a doctor from superficial examination" mean? For one thing, it was a robot and for another thing, did you not see the phallic probe that was inserted into her? The "anomaly" could have easily been detected with space age medical probing from a robot as it would have been imagined in the 70's.
Thank You! Seriously - the other thing is the bad rating of this movie in general; as if most people don't "get" it. Well, sorry, it's not STAR WARS EPISODE 2658 or whatever... it's a clever satire set in a 1970s retro-future.