What is the expected temperature change 2-4 days prior to menstruation?

During the menstrual cycle, there are distinct hormonal changes that influence body temperature. Two to four days prior to menstruation, a woman's progesterone levels begin to drop after their peak, which occurs during the luteal phase. Progesterone is known to have a thermogenic effect, typically causing a slight increase in basal body temperature.

As menstruation approaches and progesterone levels decline, the increase in temperature subsides, leading to a decrease in overall body temperature just before the onset of menstruation. This drop in temperature signals the start of the menstrual phase. In this context, the expected temperature change 2-4 days before menstruation is a decrease as the body prepares for the shedding of the uterine lining.

The other potential choices do not accurately reflect this typical pattern of temperature changes associated with the menstrual cycle.