Sci-fi Wet Dreams
Oy, the lameness. You people have been reading way too much Heinlein, and agreeing uncritically with too much of what you read.
It's not like a pregnant woman is completely useless for 9 months(!) They will be "baby factories" while also being scientists, engineers, architects, doctors, factory workers, farmers, teachers, and soldiers. Same goes for the men, 'cept perhaps for the baby factory part. Just like here on planet Earth. Maybe we'll send an all-woman crew of scientists, engineers, etc., and a few dumb, hot men to pleasure them (plus a supply of easily-stored genius sperm). Won't that disappoint the pimply male nerds running this discussion. Maybe a crew consisting of a few teachers and a whole bunch of (small, light) children.
A fundamental mistake made in this whole analysis is the pre-supposition that it will be hugely expensive to travel to the stars. Surely the challenges are daunting; learn to live indefinitely in an isolated environment; build a structure in space capable of sustaining a couple hundred people; discover a power source capable of accelerating the structure to relativistic velocities.
That's just one approach. Maybe not even the best one. Another is to build an automated womb and a teaching machine, and fly that smaller structure to the stars, perhaps more slowly. There are yet other approaches. Depends what we get good at first.
500 years ago we didn't even know how to get 100 men across a warm, familiar ocean of water with perfectly breathable air above it, and sustain them at their destination. Now anyone can buy a ticket across the ocean for a few days' wages. 50 years ago we didn't know how to get 2 men on the moon and sustain them for 3 days. 10 years later we did it, but it cost 10 billion dollars. This year a little company with less than 1000 employees is replicating the bulk of that accomplishment, and less wealthy governments have their eyes on the moon.
If we've learned anything from the space race, it's this. It's only expensive if we have to brute-force it, and pay every cent of the development cost. If we build incrementally, the cost of funding the actual expedition may be quite reasonable. One day some guy in the successor organization to DARPA will say, "Hey look, if we put technologies A, B, and C together, we've got most of what we need for a starship." and funding will be available for mankind's greatest adventure *ever*.
Maybe we're asking the wrong question. Maybe we need to be asking, "How can we get to the stars for a price we can afford? What things might make the voyage less expensive, and how can we encourage the development of these things?"
This is less fun that vast multigeneration torch-ships. It's the dream of professional engineers, not the mental masturbation of some teenage boy occupying the body of a nominal adult. It's the dream that will get us there.
Science Fiction has explored all the possibilities I've listed here for getting to the stars, and numerous others. We can't let our imagination be as constrained as Heinlein's was. And our attitudes about women need to live in the 21'st century, not stuck in the 50's with Heinlein.