Patient's question:
I got married last year. Recently, I've been experiencing lower abdominal pain, especially during my period. I'm very worried it might affect fertility, and I also feel extremely cold and afraid of the cold. Could you please tell me if having sexual intercourse during this time will affect my body?Doctor's answer:
For women with a regular menstrual cycle:Female ovulation is influenced by the cyclical changes of endocrine hormones secreted by the pituitary gland and ovaries. The lengths of both cycles are consistent, each lasting one month, with ovulation occurring between two menstrual periods. While women's menstrual cycles can vary in length, the interval between the day of ovulation and the start of the next menstrual period is relatively fixed, usually around 14 days. Based on this relationship between ovulation and menstruation, the ovulation period can be calculated according to the menstrual cycle. The calculation method is to start from the first day of the next menstrual period and count backward 14 days or subtract 14 days to determine the ovulation day. The ovulation day, along with the 5 days before it and the 4 days after it, together constitute the ovulation period. This is also the theoretical basis for the safe period method of contraception, as the days outside of the menstrual period and ovulation period are considered safe.
For example, if the menstrual cycle is 30 days long, and the first day of this period is September 29, the next menstrual period would occur on October 29 (September 29 plus 30 days). Subtracting 14 days from October 29 gives October 15 as the ovulation day. The 5 days before and 4 days after the ovulation day, i.e., October 10–19, make up the 10-day ovulation period.
To calculate the ovulation period using this method, one must first know the length of the menstrual cycle. This means having a very regular or predictable menstrual cycle to accurately determine the start date of the next menstrual period, and subsequently, the ovulation period. Therefore, this method is only suitable for women with consistently normal menstrual cycles. If the menstrual cycle is irregular or abnormal, it is impossible to predict the next menstrual period, making it impossible to calculate the ovulation day or period.
For women with an irregular menstrual cycle, the ovulation period can be calculated using the following formula:
- First day of ovulation period = Shortest menstrual cycle length minus 18 days
- Last day of ovulation period = Longest menstrual cycle length minus 11 days
For example, if the shortest menstrual cycle is 28 days and the longest is 37 days, subtract 18 from the shortest (28 – 18 = 10) and subtract 11 from the longest (37 – 11 = 26). Therefore, the period from the 10th to the 26th day after menstruation falls within the ovulation period.
Definition of the safe period: The safe period is divided into the pre-ovulation safe period and the post-ovulation safe period. The days from the day the menstrual period ends to the day before the start of the ovulation period constitute the pre-ovulation safe period.
The days from the day after the ovulation period ends to the day before the next menstrual period begins constitute the post-ovulation safe period. The post-ovulation safe period is safer than the pre-ovulation safe period.
This is because some women may experience early ovulation due to environmental changes or emotional fluctuations, which shortens the pre-ovulation safe period without their knowledge, making it less reliable. It is rare for a woman to ovulate twice in one menstrual cycle. Generally, there is no second ovulation between the time of ovulation and the start of the next menstrual period, so the post-ovulation safe period is more reliable.
From a contraceptive perspective, a woman's monthly menstrual cycle can be divided into the menstrual period, ovulation period, and safe period. Generally, women of normal fertile age release only one egg per month. After ovulation, the egg can survive for 1–2 days, while sperm can survive in the female reproductive tract for 2–3 days. Fertilization capability is highest within 24 hours after ovulation, and sperm lose the ability to fertilize an egg after 2–3 days.
Therefore, sexual intercourse 2–3 days before ovulation or 1–2 days after ovulation may result in pregnancy, which is known as the fertile period or dangerous period. A woman's ovulation date is usually about 14 days before her next menstrual period. For safety, the 5 days before ovulation, the ovulation day itself, and the 4 days after ovulation are collectively referred to as the ovulation period. The remaining days, excluding the menstrual period, are considered the safe period.