 Why did the Lieutenant go into labor early?
There, high in the emptiness of space, Space Station One swung in its orbit. Once every two hours, the artificial satellite looped completely around the planet, watching what went on below. "But that was two and a half months ago! The terrible pressure of a rocket landing would increase her effective body weight to nearly half a ton; an adult human being couldn't take that sort of punishment for long, much less the tiny life that was growing within her. The depressurization hadn't hurt her too much, but the shock had been enough to start labor.
 A slight depressurization in the space station shocked her body into labor.
 A slight depressurization in the space station shocked her body into labor.  Major Banes induced labor early because the baby was unusually large.  The stress of living in outer space caused her body to go into pre-term labor.  An asteroid crashed into the space station causing it to jerk unexpectedly. The Lieutenant fell and her water broke.