What hormonal change causes a rise in basal body temperature during the ovulation cycle?

The increase in basal body temperature during the ovulation cycle is primarily attributed to increased progesterone levels. Following ovulation, the corpus luteum, which forms from the ruptured follicle, produces progesterone. This hormone plays a crucial role in preparing the endometrium for potential implantation of a fertilized egg and also affects body temperature. Progesterone causes a slight rise in basal body temperature, typically between 0.5 to 1 degree Fahrenheit.

This temperature increase is a physiological response that can reflect ovulation and is often used by individuals tracking their fertility. The rise in temperature is not caused by estrogen, luteinizing hormone, or follicle-stimulating hormone in the same direct manner; rather, these hormones regulate different aspects of the menstrual cycle and reproductive process. Estrogen predominates during the follicular phase, and luteinizing hormone spikes just before ovulation, while follicle-stimulating hormone primarily promotes the growth of ovarian follicles and does not significantly influence temperature changes during the luteal phase.