Disease Description (Causes and Symptoms)
- Definition: Habitual miscarriage refers to a condition in which miscarriage occurs repeatedly two or more times before 20 weeks (5 months) of pregnancy.
- Main causes
- Genetic factors: A considerable proportion of spontaneous miscarriages are related to fetal chromosomal abnormalities (approximately 50–60%), but parental chromosomal abnormalities account for approximately 5% or less in recurrent miscarriage. If the couple has a balanced translocation or similar abnormality, PGT (preimplantation genetic testing) or genetic counseling may be considered.
- Hormonal·endocrine factors: Progesterone deficiency due to luteal dysfunction, hypothyroidism, diabetes, etc.
- Anatomical factors: Uterine anomalies (septate uterus, bicornuate uterus, etc.), uterine fibroids, intrauterine adhesions, cervical insufficiency (the cervix opens asymptomatically during the second trimester, resulting in prolapse of the fetus and amniotic sac), etc.
- Infection: Infection of the birth canal or uterus may adversely affect the fetus and placenta and may cause miscarriage.
- Immunological factors: Maternal immune abnormalities, such as antiphospholipid antibody syndrome, may cause implantation failure and early miscarriage.
- Pathophysiology summary: Depending on the cause, pregnancy fails to continue because of implantation problems, impaired fetal development, placental insufficiency, structural problems of the uterus, or immune or hormonal imbalance.
- Symptoms (clinical presentation): Abnormal vaginal bleeding, pelvic or abdominal pain, missed miscarriage (asymptomatic), threatened/inevitable/incomplete/complete miscarriage, etc.
- Risk of recurrence (domestic statistics): The probability of another miscarriage is approximately 15% after one miscarriage, approximately 25% for a third miscarriage after two miscarriages, and approximately 40% for a fourth miscarriage after three miscarriages.
Treatment Methods and Precautions
- Cause-specific approach (based on standard recommendations)
- Genetic abnormalities: Karyotype testing of both partners and genetic counseling. If one parent has a balanced translocation, IVF+PGT may be considered.
- Antiphospholipid antibody syndrome: Combined treatment with low-dose aspirin and low-molecular-weight heparin (LMWH) is the standard treatment and may help improve the rate of maintaining pregnancy.
- Hormonal abnormalities: Progesterone supplementation (when luteal phase deficiency is suspected) or control of thyroid disease and diabetes.
- Anatomical abnormalities: Surgical correction (metroplasty) of a uterine septum or similar abnormality, or removal of uterine fibroids; for cervical insufficiency, conservative management (cerclage) or cervical cerclage, depending on the situation.
- Infection: Appropriate antibiotic treatment after identification of the causative pathogen.
- Testing and treatment process: When there is a history of recurrent miscarriage, tests to identify the cause (karyotyping of both partners, blood tests [antiphospholipid antibodies, thyroid function, blood glucose, etc.], uterine imaging [ultrasound, hysterosalpingography], hysteroscopy/laparoscopy, etc.) → specific treatment according to the cause.
- Lifestyle management and precautions
- Smoking cessation and limiting alcohol are recommended. Regular excessive alcohol consumption increases the risk of miscarriage (abstinence is recommended).
- Avoid excessive caffeine intake (500 mg or more per day).
- Avoid unnecessary radiographic examinations. Consult the attending physician when taking medication.
- Avoid excessive physical stress, such as heavy labor, overwork, standing for long periods, strenuous exercise, and impact (blunt trauma to the abdomen). Follow the doctor's instructions regarding sexual intercourse if there is a risk of miscarriage or preterm birth.
- Emergency warning signs: If heavy bleeding, persistent or severe abdominal pain, fever (suggesting infection), marked tachycardia, hypotension, or similar symptoms occur, visit the emergency room immediately.
Outpatient Visit Checklist (Preparation, Records, and Example Questions)
- Items and documents to bring
- A list of currently used medications and supplements (including dosage and duration of use).
- Previous obstetrics and gynecology medical records: Test results related to previous miscarriages (pathology and tissue examination results), ultrasound images and reports, and surgical records (such as uterine surgery).
- Information about family history and genetic diseases in either partner.
- Menstrual and pregnancy history (number of pregnancies, number and timing of miscarriages, symptoms), and records of the pattern of recent bleeding and pain (onset time and characteristics).
- Lifestyle habits (smoking, alcohol, and caffeine intake) and occupational exposures (radiation and hazardous substances).
- Tests that may be performed during the outpatient visit: Pelvic ultrasound, blood tests (antiphospholipid antibodies, thyroid function, glycated hemoglobin, etc.), parental karyotype testing, hysterosalpingography, or hysteroscopy/laparoscopy, etc.
Examples of General Questions to Ask the Doctor
- "What do you think is the most likely cause of my recurrent miscarriages?"
- "Which tests do you recommend, and when will each test be performed?"
- "What treatment options are available in my situation (medications, surgery, assisted reproductive technology)?"
- "What side effects or risks are associated with the treatment?"
- "How long should I wait before trying for the next pregnancy? Is there any recommendation regarding the interval between pregnancies?"
- "How can my prognosis be predicted, and what recommendations can help increase the chances of a successful pregnancy?"
Examples of Disease-Specific Questions
- "If a balanced translocation is found on karyotype testing of both partners, is IVF+PGT recommended in my case? What are the success rate, cost, and risks?"
- "If the antiphospholipid antibody test is positive, when and how should aspirin and heparin be started as standard treatment? What is the treatment duration and monitoring plan?"