Menstruation comes 17 days after ovulation

Generally, menstruation does not occur during the ovulation period, and it is also the best time for contraception, which makes accidental pregnancy less likely. However, some female friends only get their menstruation 17 days after the ovulation period. This is actually abnormal. Usually, menstruation occurs before the ovulation period. Therefore, if you encounter this situation, you should go to the hospital for a detailed examination.

Female ovulation is affected by endocrine hormones from the pituitary gland and ovaries and changes periodically. The length of the cycles of the two is the same, with one cycle per month, and ovulation occurs between two menstrual periods. Women's menstrual cycles vary in length, but the interval between ovulation and the start of the next menstruation is relatively fixed, usually around 14 days. Based on the relationship between ovulation and menstruation, the ovulation period can be calculated according to the menstrual cycle. The calculation method is to count from the first day of the next menstrual period, and count down 14 days or subtract 14 days to get the ovulation day. The ovulation day and the 5 days before and 4 days after the ovulation day are called the ovulation period. This is also the theoretical basis of the safe period contraceptive method, because in the menstrual cycle, except for the menstrual period and ovulation period, the rest of the time is the safe period.

For example, if the menstrual cycle is 30 days, the first day of this menstruation is September 29, then the next menstruation will be on October 29 (September 29 plus 30 days), and then subtract 14 days from October 29, then October 15 is the ovulation day. The ovulation day and the 5 days before and 4 days after, that is, the ten days from October 10th to 19th are the ovulation period.

To calculate the ovulation period using this method, you must first know the length of your menstrual cycle, that is, you must have a very normal or regular menstrual cycle, in order to calculate the start date of the next menstrual period and then the ovulation period. Therefore, this method is only suitable for women with normal menstrual cycles. If the menstrual cycle is irregular or abnormal, it is impossible to calculate the date of the next menstrual period, so it is impossible to calculate the ovulation day and ovulation period.

For irregular menstruation, the formula for calculating ovulation is: First day of ovulation = the number of days in the shortest menstrual cycle minus 18 days;

The last day of ovulation = the longest menstrual cycle minus 11 days.

For example, the shortest menstrual period is 28 days and the longest is 37 days. The shortest regular period is subtracted by 18 (28-18=10) and the longest regular period is subtracted by 11 (37-11=26). Therefore, the ovulation period is from the 10th day to the 26th day after the menstrual period.