Spending extended amounts of time in zero gravity has profound effects on the human body, most of them negative. Pregnancy is already very tough, and we know literally nothing about the additional challenges associated with it (and with childbirth) in a zero G environment, or on another planet.
From this perspective, there may be some merit to the parent poster's argument that human "factories" may be less risky for everyone involved, since it might be easier to control the conditions.
We’ve sent pregnant rats into space. We know a lot about zero g rat babies and moms. Long term more serious issues are space radiation effects. Nobody has any idea how to practically solve that issue.
From this perspective, there may be some merit to the parent poster's argument that human "factories" may be less risky for everyone involved, since it might be easier to control the conditions.