The basal body temperature drops by about 0.3 to 0.5°C when the fertilized egg is deposited. Generally, after ovulation, the basal body temperature of a woman will rise slightly, mainly according to the increase in hormone levels. When the fertilized egg is implanted, due to the stimulation of the thermoregulatory center by progesterone levels, there may be a transient decrease in basal body temperature of about 0.3 to 0.5℃. After the successful fertilization of the egg, the basal body temperature will rise, so this basal body temperature decrease is transient. Generally after intercourse during ovulation, you can determine whether you will be pregnant by monitoring your basal body temperature. If the increase in basal body temperature after ovulation lasts for more than 16 days, it means that pregnancy is more likely. If you want to determine whether you are pregnant or not, you still need some means of examination.