Mittelschmerz—or ovulation pain, as it is commonly known today—is a benign preovulatory lower abdominal pain that occurs midcycle (between days 7 and 24) in women. Mittelschmerz may affect over 40% of women of reproductive age, and it occurs almost every month in these patients. It generally does not begin until a few years following menarche when the true ovulatory cycles become established. Pain varies in severity from a mild ache to agonizing pain and is generally felt near the ovaries on the same side as the developing follicle. Mittelschmerz has been found to coincide with the peak in plasma luteinizing hormone (LH) levels when the follicle is enlarging and has not yet ruptured; however, mittelschmerz is unlikely due to follicular distention. Rather, the LH rise increases ovarian perifollicular smooth muscle contractility via a prostaglandin-mediated pathway, which may produce the pain.[rx][rx][rx][rx]
Mittelschmerz (German: “middle pain”) is a medical term for “ovulation pain” or “midcycle pain”. About 20% of women experience mittelschmerz, some every cycle, some intermittently.
Causes of Mittelschmerz
Mittelschmerz is believed to have a variety of causes
The exact cause of mittelschmerz is unknown, but possible reasons for the pain include these:
- Just before an egg is released with ovulation – follicle growth stretches the surface of your ovary, causing pain.
- Blood or fluid released – from the ruptured follicle irritates the lining of your abdomen (peritoneum), leading to pain.
- Follicular swelling – The swelling of follicles in the ovaries prior to ovulation. While only one or two eggs mature to the point of being released, a number of follicles grow during the follicular phase of the menstrual cycle (non-dominant follicles atrophy prior to ovulation). Because follicles develop on both sides, this theory explains mittelschmerz that occurs simultaneously on both sides of the abdomen.[rx]
- Ovarian wall rupture – The ovaries have no openings; at ovulation, the egg breaks through the ovary’s wall. This may make ovulation itself painful for some women.[rx]
- Fallopian tube contraction – After ovulation, the fallopian tubes contract (similar to peristalsis of the esophagus), which may cause pain in some women.[rx]
- Smooth muscle cell contraction – At ovulation, this pain may be related to smooth muscle cell contraction in the ovary as well as in its ligaments. These contractions occur in response to an increased level of prostaglandin F2-alpha, itself mediated by the surge of luteinizing hormone (LH).[rx]
- Irritation – At the time of ovulation, blood or other fluid is released from the ruptured egg follicle. This fluid may cause irritation of the abdominal lining.
Symptoms of Mittelschmerz
Mittelschmerz is characterized by
- lower abdominal and pelvic pain that occurs roughly midway through a woman’s menstrual cycle.
- The pain can appear suddenly and usually subsides within hours, although it may sometimes last two or three days.[rx]
- In some cases, it can last up to the following cycle. In some women, the mittelschmerz is localized enough so that they can tell which of their two ovaries provided the egg in a given month.
- Because ovulation occurs on a random ovary each cycle, the pain may switch sides or stay on the same side from one cycle to another.
- Pain with urination
- Redness or burning of the skin at the site of the pain
- Vomiting
- Mid-cycle pain lasting longer than a day
- On one side of your lower abdomen
- Dull and achy, similar to menstrual cramps
- Sharp and sudden
- Accompanied by slight vaginal bleeding or discharge
- Rarely, severe
Women may notice other physical symptoms associated with their mittelschmerz, during or near ovulation. The most common sign is the appearance of fertile cervical mucus in the days leading up to ovulation. Cervical mucus is one of the primary signs used by various fertility awareness methods. Other symptoms are sometimes called secondary fertility signs to distinguish from the three primary signs.[rx]
- Mid-cycle or ovulatory bleeding is thought to result from the sudden drop in estrogen that occurs just before ovulation. This drop-in hormone can trigger withdrawal bleeding in the same way that switching from active to placebo birth control pills does. The rise in hormones that occurs after ovulation prevents such mid-cycle spotting from becoming as heavy or long-lasting as typical menstruation. Spotting is more common in longer cycles.[rx]
- A woman’s vulva may swell just prior to ovulation, especially the side on which ovulation will occur.[rx]
- One of the groin lymph nodes (on the side on which ovulation will occur) will swell to about the size of a pea, and may become tender.[rx]
Diagnosis of Mittelschmerz
Diagnosis of mittelschmerz is generally made if a woman is mid-cycle and a pelvic examination shows no abnormalities. If the pain is prolonged and/or severe, other diagnostic procedures such as an abdominal ultrasound may be performed to rule out other causes of abdominal pain.
The pain of mittelschmerz is sometimes mistaken for appendicitis and is one of the differential diagnoses for appendicitis in women of childbearing age.
A pelvic exam shows no problems. Other tests (such as an abdominal ultrasound or transvaginal pelvic ultrasound) may be done to look for other causes of ovarian or pelvic pain. These tests may be done if the pain is ongoing. In some cases, the ultrasound may show a collapsed ovarian follicle. This finding helps support for the diagnosis.
Treatment of Mittelschmerz
The pain is not harmful and does not signify the presence of disease. No treatment is usually necessary.
- Pain relievers (analgesics)- such as NSAIDS (Non-steroidal anti-inflammatories) may be needed in cases of prolonged or intense pain.[rx] For the relief of discomfort from mittelschmerz, try an over-the-counter drug such as acetaminophen (Tylenol, others), aspirin, ibuprofen (Advil, Motrin IB, others), or naproxen sodium (Aleve).
- Birth control pills (oral contraceptives). If mittelschmerz causes you a lot of discomforts or occurs monthly, ask your doctor about taking birth control pills. Some types of birth control pills suppress ovulation, which could help ease ovulation pain while you’re taking them.
- Hormonal forms of contraception – can be taken to prevent ovulation[rx]—and therefore ovulatory pain—but otherwise there is no known prevention.
- Birth control methods – that stop ovulation, such as the contraceptive pill or contraceptive implant, can completely banish ovulation pain.
Lifestyle and home remedies
To ease mittelschmerz discomfort that lasts more than a few minutes, try some home remedies. Because heat increases blood flow, relaxes tense muscles and eases cramping, you might want to:
- Soak in a hot bath
- Use a heating pad where the pain is
What you can do
You may want to write a list that includes:
- Detailed descriptions of your symptoms
- The dates when your last two menstrual periods began
- Information about medical problems you’ve had
- Information about the medical problems of your parents or siblings
- All the medications and dietary supplements you take
- Questions to ask the doctor
Preparing a list of questions for your doctor will help you make the most of your time together. For mittelschmerz, some basic questions to ask include:
- What is likely causing my symptoms?
- Are there other possible causes for my symptoms?
- Are my symptoms likely to change over time?
- Do I need tests?
- What treatments or home remedies might help?
- Do you have brochures or other printed materials I can have? What websites do you recommend?
Don’t hesitate to ask other questions, as well.
What to expect from your doctor
Your doctor is likely to ask you a number of questions, such as:
- How many days apart are your menstrual periods, and how long do they last?
- How would you describe your symptoms?
- Where is your pain?
- How long have you been experiencing this pain? Is it constant or does it subside after a few minutes or hours?
- On a scale of 1 to 10, how severe is your pain?
- How long before or after your period does the pain occur?
- Do you have other symptoms, such as nausea, vomiting, diarrhea, back pain, dizziness or headache?
References
