Maternity leave
Real world article
(written from a production point of view)
Mentioned in the script for Star Trek IV: The Voyage Home, but not filmed, maternity leave was a leave of absence taken by a pregnant woman until some time after her baby was born, for recovery and bonding purposes.
Saavik, who was supposed to have become impregnated by a pon farr-afflicted Spock on the Genesis Planet, informed James T. Kirk that she was taking a maternity leave. (The Making of the Trek Films, 3rd ed., p. 64)