Gastric emptying of both solid- and liquid-phase markers was assessed in 7 normally-menstruating women who had undergone bilateral Fallopian tube ligations. The women were studied once during the follicular phase of their menstrual cycle and again during the luteal phase. Emptying of the liquid-phase marker was not significantly different during the two phases of the menstrual cycle. However, emptying of the solid-phase marker was significantly slower during the luteal phase of the cycle as compared to the follicular phase. This impairment of gastric emptying of solid was correlated with elevated serum levels of progesterone. This study demonstrates that the rate of gastric emptying of solids may vary with the phases of the menstrual cycle.