Doc Newton's early history or world of origin is unknown. Given her accent, it was possibly England, Earth; although theoretically it could have been anywhere in Earth's Solar System. Io was known for its further education facilities, so it is possible that Doc Newton received her professional training there.
Three million years later
Doc Newton caught up with Captain Hollister in the corridor, and asked why Red Dwarf is now three million years into Deep Space. It was supposed to be classified information, but Doc Newton was told by the coffee machine on G-Deck. Captain Hollister angrily said that he will demote the machine down to tampon dispenser.
In the medical room, "stowaway" The Cat was examined by the medical staff headed by Doc Newton, and confuses them with his six nipples, musical heartbeat and multi-coloured intestines. Cat says that the females of his species are "pretty easy to please in bed". The Captain loved the sound of Cat's heartbeat so much, that he began dancing to it and asked Doc Newton to get it down on tape for him.
During dinner at Captain Hollister's table, Arnold Rimmer had taken the sexual magnetism virus (which he had recovered from the crashed Starbug from the earlier Red Dwarf) in a very large dose and charms everyone. While the women look at him adoringly, Rimmer impresses Hollister with his theories on future echoes, and universes where time runs backward, and how Drive Plates could potentially be very dangerous. Rimmer soon finds the sexual magnetism virus is not so great, as every time he gets up to fetch refreshments a female guest follows him and forces him to have sex with her in a locker room, including Doc Newton. This successively wears Rimmer down further and further, and forcing encounters with those large, matronly-types he would prefer not to be with. (Back in the Red)
When Red Dwarf came under attack by the Chameleonic Microbe, Doc Newton evacuated Red Dwarf along with Captain Hollister and the rest of the officers on a fleet of shuttle craft. ("Only the Good...") Although Red Dwarf was saved by the regular characters, the fate of Doc Newton and the others has, so far, remained unresolved.