Common basal body temperature changes are explained: 1. Ovulation: When a woman is menstruating, the basal body temperature is low; after ovulation, the basal body temperature will turn to high. Generally speaking, the rate of fertilization becomes lower for women 24 hours after ovulation; however, male sperm can survive in a woman’s uterus for about 72 hours. Therefore, you should have intercourse when the woman’s basal body temperature is at a low temperature and close to ovulation, you can have intercourse every two days to increase the chance of fertilization; if you wait until the basal body temperature reaches a high temperature and then have intercourse, the chance of pregnancy will have been reduced. 2, polycystic ovary syndrome: such patients to “fat” as a symptom, often easy to fat, acne, thick hair, menstruation regularly inaccurate. The performance in the basic body temperature is: high temperature period is short, serious may also be regular low temperature. Women with this condition usually have familial genetic diabetes, and if they are pregnant with a child, they belong to a high risk group for gestational diabetes. 3, poor ovarian function: people with poor ovarian function, usually the cycle of basal body temperature will be shortened, the original 28 days, may slowly become 24 days or 22 days, the high temperature period is also shortened accordingly. 4. High lactogen: If lactogen is high, the high temperature period of the basal body temperature will be shortened and the quality of their eggs will be poorer, so they will not get pregnant easily or will miscarry easily. 5.Dangerous period (easy to conceive period): The high temperature period of basal body temperature belongs to the safe period (not easy to conceive period), and the low temperature period belongs to the dangerous period, but there are individual differences in the low temperature period. For example, for young girls, who have good ovarian function and more secretions, the danger period is correspondingly longer and the chances of sperm survival in the uterus will be relatively high. Therefore, it is likely that the risk period must be seen as starting 5 days before ovulation.