I think circumstantial evidence hints that the surgical pod was limited to men so the filmmakers could avoid mentioning abortion.
Consider:
A. It seems odd and arbitrary that the script calls for a machine that is advanced enough to perform a wide array of medical procedures on a man but cannot perform most or all of those procedures on a woman. For one thing, there is more variation within gender than between gender. Also, limiting the machine to men would cut in half the machine's return on investment. Overall, the men-only constraint feels forced.
B. if the script had allowed for the machine to treat both men and women, the procedure Elizabeth Shaw would have requested would have been "abortion" or "termination of pregnancy" or something similar
C. abortion is one of the most controversial topics in the world
By restricting the machine to men-only treatment, the filmmakers avoided having to broach the abortion issue. Instead, Elizabeth Shaw commanded the machine to "remove foreign object," avoiding any abortion-related terminology.