Star Trek: Enterprise: Season 1, Episode 5

1 - 5: Unexpected

After discovering the presence of a damaged Xyrillian vessel, Archer dispatches Trip to assist with its power source problems. He is delighted to have a friendly encounter with one of the ship's female engineers, but it has an unexpected side effect. After discovering that their special moment resulted in his becoming pregnant, he realizes he's had an unwitting experience with alien sex. Archer and his crew must then try and return the rapidly growing alien baby to its mother.