Patient's question:
I got my period on November 6th and it ended on the 11th. On the 16th, the ovulation test strip showed negative. On the 20th, the test line was very faint. It wasn't until the 22nd that it turned strongly positive, and by the 26th, it was still strongly positive. On the 30th, which is today, the control line is very faint, while the test line is deep red-purple. What could be going on? Am I pregnant? But the expert said the test is positive, yet it won't lead to pregnancy. How do you explain this phenomenon? Frustrated! Please help the expert explain this. Thank you!Doctor's answer:
The method of calculating ovulation based on the menstrual cycle is also known as the calendar method. Both menstruation and ovulation are influenced by endocrine hormones from the pituitary gland and ovaries, exhibiting cyclical changes. The lengths of both cycles are consistent, with each lasting one month, and ovulation occurs between two menstrual periods. A woman's menstrual cycle can vary in length, but the interval between the day of ovulation and the start of the next menstrual period is relatively fixed, generally around 14 days. Based on this relationship between ovulation and menstruation, it is possible to calculate the ovulation period according to the menstrual cycle. The calculation method starts from the first day of the next menstrual period, subtracting 14 days (or counting backward 14 days) to determine the ovulation day. The days before the ovulation day (5 days) and after it (4 days) together constitute the ovulation period. This is the theoretical basis for the safe period method of contraception. For example, if a woman has a 28-day menstrual cycle and her first day of the current menstrual period is December 2, her next menstrual period will occur on December 30 (December 2 plus 28 days). Subtracting 14 days from December 30 gives December 16 as the ovulation day. The ovulation period, which includes the ovulation day and the 5 days before and 4 days after, is from December 11 to December 20.