Final answer:
Leto was in labor for nine days and nights due to Hera's curse which prevented her from giving birth on solid land until she reached the island of Delos.
Step-by-step explanation:
In ancient Greek mythology, Leto, also known as Latona, experienced prolonged labor due to the goddess Hera's jealousy and curse. Hera banned Leto from giving birth on terra-firma, or the mainland, and any island at sea.
Eventually, Leto found refuge on the floating island of Delos, which was neither mainland nor a real island, and there she finally gave birth to her twins, Apollo and Artemis. While the exact time is not specified in all sources, some versions of the myth suggest that Leto suffered labor for nine days and nights before giving birth to the divine twins.