Well it should be upsetting since Walter is an android...
Back in the old eu, robots were used by the company to gather eggs because they were immune. While that is no longer canon, I still think androids will be incapable of carrying embryos.
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That's a common plot device in the EU to be sure, but I don't think I ever fully bought that concept. The queen definitely took note of Bishop in Aliens right? If Aliens as a sequel is canon then it definitely implies that the aliens aren't exactly passive towards androids.