What is Mittelschmerz?
Mittelschmerz is midcycle, one-sided (unilateral), lower abdominal pain which occurs in some women at or around the time of ovulation. Mittelschmerz is a German word. “Mittel” means “middle”, while “schmerz” means “pain”. Ovulation or the release of the ovum (egg) from the ovary usually occurs around day 14 of a 28-day menstrual cycle, which is around the middle of a menstrual cycle, hence the name midcycle pain or ovulation pain. The occurrence of midcycle pain is quite common, particularly in teenagers and older women. Usually mild, in some cases the pain may become quite intolerable.
Cause of Mittelschmerz
The ovaries are situated on either side of the uterus, close to the fimbriated end of the fallopian tubes. There are many primordial follicles present under the ovarian capsule, each containing an immature ovum. At the beginning of each menstrual cycle, several of these follicles start to grow but by about day 6 of the cycle only one of the follicles in one ovary grows to form the dominant follicle.The rest of the follicles disintegrate.
Around the 14th day of the menstrual cycle, the distended follicle ruptures and the ovum is released. This process is known as ovulation. As the ruptured follicle fills with blood, a small amount of the blood from the follicle may escape into the abdominal cavity causing peritoneal irritation. This is the cause of fleeting lower abdominal pain at midcycle, during ovulation, which is known as mittelschmerz.
Another theory is that stretching of the ovarian capsule due to follicular growth is the cause of midcycle pain.
Symptoms of Mittelschmerz
Cramping pain in the lower abdomen and pelvis which may last from a few minutes to several hours. Rarely, the pain may continue for 24 to 48 hours.
- The pain is usually unilateral and may be felt on either side of the abdomen.
- The pain may or may not be on the same side of the abdomen every month.
- Usually occurs during the middle of a menstrual cycle, about 14 days before the next menstrual period.
- The intensity of pain may range from mild to severe.
- Nausea may occur with severe pain.
- The pain may be accompanied by slight vaginal bleeding or spotting.
Diagnosis of Mittelschmerz
The history of the pain is usually indicative of mittelschmerz. No abnormalities are found on physical examination. Ultrasound may be done to rule out other causes of abdominal or pelvic pain. Appendicitis and ectopic pregnancy are the two most important conditions that should be excluded as the cause of pain. Keeping a menstrual diary may help in diagnosis of midcycle pain.
Treatment of Mittelschmerz
There is no specific treatment for mittelschmerz. Simple home remedies such as a warm bath or use of a heating pad on the abdomen may suffice to relieve mild pain. Pain relievers may be used in case of severe pain. Over-the-counter drugs such as acetaminophen (paracetamol), aspirin, or ibuprofen may help. Oral contraceptives or birth control pills may be taken, which will prevent ovulation and thereby reduce or prevent midcycle pain.
Outcome of Mittelschmerz
Mittelschmerz does not lead to any serious complications. It gives an indication of the time of ovulation and may be helpful for women who are trying to get pregnant since this is the most fertile period of the menstrual cycle. It is also an indication that ovulation is taking place.