The mission’s early conclusion left the space station temporarily staffed by just three astronauts — one American and two Russians — a configuration NASA said is manageable but limits some operations.
Agency officials said no spacewalks, including emergency repairs, can be conducted until the arrival of the next crew.
NASA stressed that the decision was precautionary and not the result of an emergency. The health issue emerged on Jan. 7, prompting the cancellation of a scheduled spacewalk the following day and ultimately leading to the shortened mission.
It marked the first time NASA has cut short a spaceflight for medical reasons, though similar decisions were made by Russian space programs decades ago.
NASA and SpaceX said they are working to move up the launch of a replacement crew of four, currently scheduled for mid-February.