12.5 Spontaneous & Recurrent Abortion: Recognition & Management
Key Takeaways
- Abortion is expulsion of a fetus before 20 weeks gestation or below 500 g; types are defined by the state of the cervical os and bleeding — threatened (closed, mild bleeding), inevitable (open, bleeding, membranes may rupture), incomplete (open, products passed, ongoing bleeding), complete (closed, bleeding settled) and missed (closed, fetus dead, retained).
- Septic abortion is a life-threatening uterine infection with foul discharge, fever, pelvic pain and tenderness; management is broad-spectrum IV antibiotics, uterine evacuation and supportive care, with vigilance for septic shock and ARDS.
- Recurrent (habitual) abortion is ≥3 consecutive losses; antiphospholipid syndrome is the most important treatable cause and is managed with low-dose aspirin plus heparin in pregnancy.
- Missed miscarriage is managed expectantly, medically (misoprostol) or surgically (suction evacuation) depending on gestation, preference and clinical stability.
- Ectopic pregnancy must always be excluded in any woman of reproductive age with bleeding and pain — a closed cervix with bleeding and adnexal tenderness can mimic threatened abortion.
12.5 Spontaneous & Recurrent Abortion: Recognition & Management
High-Yield Core Concept: The OBGYN syllabus lists Abortions and Intra-Uterine Growth Retardation under high-risk pregnancy. CMS stems hinge on classifying the miscarriage by the state of the cervical os, recognising septic abortion, and knowing the work-up of recurrent loss.
1. Definitions & Classification
Abortion = expulsion or extraction of a fetus before 20 weeks gestation or weighing <500 g.
| Type | Cervical os | Bleeding | Other features | Management |
|---|---|---|---|---|
| Threatened | Closed | Mild, spotting | No products passed; fetal cardiac activity present on USG | Reassurance, rest, avoid intercourse |
| Inevitable | Open | Moderate–severe | Membranes may rupture; cramping | Analgesia; await completion or evacuation |
| Incomplete | Open | Heavy, ongoing | Products partially passed | Suction/evacuation to complete |
| Complete | Closed | Settled | All products passed; uterus small, firm | Observe; anti-D if Rh-negative |
| Missed | Closed | Brownish/absent | Fetus dead but retained; small-for-dates uterus | Expectant / medical (misoprostol) / surgical evacuation |
| Septic | ±Open | Foul-smelling | Fever, uterine tenderness, peritonism | Emergency: antibiotics + evacuation + support |
Clinical triad of miscarriage: bleeding + cramping lower-abdominal pain + (closed or open) cervix. Always record the state of the os — it determines the diagnosis.
2. Septic Abortion
Most often follows unsafe/illegal induced abortion but complicates any retained products. Causative organisms include E. coli, anaerobes, Gram-negative bacilli, Clostridium.
Clinical: fever, tachycardia, foul-smelling vaginal discharge, uterine tenderness, abdominal guarding; may progress to septic shock, ARDS, renal failure, DIC.
Management (emergency):
- Resuscitate — IV fluids, oxygen, haemodynamic monitoring; blood for CBC, cross-match, coagulation, cultures.
- Broad-spectrum IV antibiotics early (e.g. ampicillin/ceftriaxone + gentamicin + metronidazole, or a carbapenem in severe sepsis).
- Uterine evacuation (suction or D&E) once stable; oxytocin to reduce blood loss.
- Supportive ICU care for shock, ARDS, DIC; hysterectomy if uterine necrosis/perforation uncontrolled.
3. Recurrent (Habitual) Abortion
Defined as ≥3 consecutive spontaneous abortions. Causes:
| Category | Examples |
|---|---|
| Genetic | Parental balanced translocation (reciprocal/Robertsonian), fetal aneuploidy |
| Anatomic | Uterine septum, submucosal fibroid, cervical incompetence (history of painless mid-trimester loss) |
| Endocrine | Uncontrolled diabetes, hypothyroidism, hyperprolactinaemia |
| Immunological | Antiphospholipid syndrome (APS) — most important treatable cause; also alloimmune |
| Thrombophilic | Factor V Leiden, protein C/S deficiency |
| Infective | Toxoplasma, Listeria, syphilis, BV |
Work-up: parental karyotype, TSH, anticardiolipin + lupus anticoagulant (repeat 12 weeks apart), pelvic ultrasound/hysteroscopy/SIS for uterine anatomy, cervical length surveillance if cervical incompetence.
Antiphospholipid syndrome criteria: ≥3 consecutive losses <10 weeks, or ≥1 loss ≥10 weeks, or severe pre-eclampsia/ placental insufficiency, plus persistent positive antiphospholipid antibodies. Treatment: low-dose aspirin + unfractionated/LMWH heparin in pregnancy improves live-birth rate.
4. Molar Pregnancy (Hydatidiform Mole)
A cause of bleeding in early pregnancy that must not be missed. Complete mole (all paternal DNA, no fetus) and partial mole (triploid, partial fetal tissue).
Clinical: first-trimester bleeding, uterus large for dates, excessive vomiting (hyperemesis, high β-hCG), passage of vesicles, bilateral theca-lutein cysts, early pre-eclampsia.
USG: 'snowstorm' appearance, absent fetal cardiac activity (complete).
Management: suction evacuation (careful, oxytocin running to avoid perforation/embolisation), send products for histology, then serial β-hCG follow-up until undetectable and for 6 months thereafter to detect persistent trophoblastic disease / choriocarcinoma; reliable contraception during surveillance.
5. Differential: Bleeding + Pain in Early Pregnancy
Always consider ectopic pregnancy — abdominal pain, vaginal bleeding, amenorrhoea, adnexal tenderness/mass, and a β-hCG below the discriminatory zone (~1,500–2,000 IU/L) with no intrauterine gestation on transvaginal USG. A closed cervix with mild bleeding may mimic threatened abortion; adnexal tenderness or a mass and a positive pregnancy test with an empty uterus mandate ectopic assessment.
6. Cervical Incompetence & Threatened Abortion Management in Detail
Cervical incompetence (cervical insufficiency) is a distinct, surgically-treatable cause of second-trimester loss that candidates must not confuse with first-trimester miscarriage. The classic history is painless, progressive cervical dilation and expulsion of a live fetus in the second trimester with minimal cramping, often recurrent. Risk factors include prior cervical surgery (cone biopsy), trauma (dilation, MTP), and connective-tissue disorders.
Management — cervical cerclage (Shirodkar/McDonald suture):
- History-indicated (prophylactic) at 12–14 weeks after one or more prior second-trimester losses.
- Ultrasound-indicated when serial transvaginal scans show cervical shortening (<25 mm) before 24 weeks.
- Rescue/emergency when dilation is detected on examination but membranes are unruptured — lower success.
- Cerclage is removed at 36–37 weeks (or earlier if labour/PPROM/infection) and is contraindicated with active bleeding, infection, ruptured membranes or a fetus already non-viable.
Threatened abortion with viable pregnancy — light bleeding, closed os, fetal cardiac activity present. Management is reassurance, pelvic rest and avoidance of heavy exertion; progesterone supplementation has limited evidence and is reserved for a history of recurrent loss. Most threatened abortions resolve and proceed to a live birth. Anti-D for Rh-negative women. Arrange ultrasound to confirm viability and exclude subchorionic haematoma.
Worked scenario: a woman with two prior painless mid-trimester losses at 18 weeks presents at 11 weeks wanting prevention — history-indicated cervical cerclage at 12–14 weeks is the evidence-based choice, distinguishing her cervical incompetence from recurrent first-trimester miscarriage (which would prompt antiphospholipid screening instead).
Key Takeaways for the CMS Candidate
- State of the cervical os defines threatened vs inevitable vs incomplete miscarriage — the favourite discriminator.
- Septic abortion = emergency: antibiotics + evacuation + ICU support.
- Recurrent loss = ≥3 consecutive; the treatable cause is antiphospholipid syndrome → aspirin + heparin.
- Molar pregnancy → suction + 6-month serial β-hCG surveillance for choriocarcinoma.
- Bleeding + pain + empty uterus on USG → exclude ectopic.
A woman at 9 weeks gestation presents with heavy vaginal bleeding and cramping pain; speculum shows the cervical os is open and tissue is visible. Ultrasound confirms retained products. What is the most appropriate management?
A 30-year-old has had three consecutive first-trimester miscarriages. Which is the most important treatable cause to screen for, and what is the evidence-based management?