Is there a chance of pregnancy during intercourse during menstruation?
Jan 04, 2022
Source: Cainiu Health
Dr. Chen Yunmei
Introduction
The menstrual cycle includes the menstrual phase, ovulation phase, and safe period. A woman can become pregnant primarily during the ovulation phase, when an egg is released and can combine with sperm to form a fertilized egg—thus enabling successful conception. Under normal circumstances, women ovulate only once per month—specifically on the day of ovulation—and typically release just one egg. Therefore, the likelihood of pregnancy from intercourse during menstruation is relatively low.
First and foremost, it should be emphasized that pregnancy during menstruation is highly unlikely, as ovulation does not occur at this time. However, sexual intercourse during menstruation is generally not recommended, because women are in an exceptionally vulnerable physiological state. Engaging in intercourse during this period increases the risk of infection—and in severe cases, may even lead to infertility. Therefore, selecting appropriate contraceptive methods is critically important.
Is Pregnancy Possible During Menstruation?
The menstrual cycle comprises three phases: the menstrual phase, the ovulatory phase, and the safe (non-fertile) phase. Pregnancy occurs primarily during ovulation, when an egg is released and can combine with sperm to form a fertilized egg. Under normal circumstances, women ovulate only once per cycle—typically on a single day—and release just one egg. Consequently, the likelihood of conception during menstruation is very low. However, certain medications—such as hormonal contraceptives—may disrupt the menstrual cycle and cause irregular or unexpected ovulation, including rare instances of ovulation occurring during menstruation.
Sexual Intercourse During Menstruation May Lead to Infertility
The primary reproductive health risk associated with intercourse during menstruation is infertility. During this time, the uterine lining is shedding, creating micro-tears and exposing blood cells. Sperm may encounter these damaged endometrial sites and even enter the bloodstream, potentially triggering an immune response. This may lead to the production of anti-sperm antibodies—found in cervical mucus and serum—which subsequently provoke an immunological rejection reaction upon re-exposure to sperm, thereby impairing sperm-egg interaction and fertilization.
Increased Risk of Vulvar Inflammation and Swelling
If sexual intercourse occurs during menstruation, men should use condoms—ideally dual-protection methods (e.g., condoms combined with another contraceptive method). This is because menstrual secretions may enter the male urethra, causing urethral irritation. Moreover, reduced vaginal lubrication due to blood flow increases friction during intercourse, potentially resulting in inflammation and swelling of the vulva.
Exacerbated Menstrual Bleeding
Menstruation involves active uterine bleeding. During sexual climax, uterine contractions intensify—particularly if intercourse occurs during the first half of the menstrual period—potentially leading to significantly increased menstrual flow. Therefore, if intercourse is undertaken during this time, precautions should be taken to avoid soiling bedding.
Risk of Endometriosis
Menstruation is the physiological process by which the uterine lining (endometrium) sheds and exits the body through the vagina. If intercourse occurs during this period, retrograde flow of menstrual blood containing endometrial tissue may be forced backward into the pelvic cavity instead of being expelled outward—thereby increasing the risk of endometriosis.
We hope the above information is helpful. Wishing you good health and happiness!
