A Short Review of Spontaneous Abortion or Miscarriage
Abortion is defined as the termination of pregnancy, either spontaneously or intentionally:
1. Prior to age of viability (28 weeks) OR
2. < 500 gm birth weight
Common Causes of Spontaneous Abortion (Miscarriage):
A) 1st trimester (GEI)
- Genetic factors: Autosomal trisomy, Polyploidy, Monosomy X, Mosaic, Double trisomy
- Endocrine disorders: Luteal phase defect (LPD), Thyroid abnormalities, DM
- Immunological: Autoimmune (ANAs, Anti-DNA antibodies, Anti-phospholipid antibodies), Alloimmune, Antifetal antibodies (Rh isoimmunization)
- Infection (ToRCH, Ureaplasma, Chlamydia, Brucella, Malaria)
- Unexplained
B) 2nd trimester (AM)
- Anatomic abnormalities: Cervical incompetence, Mullerian fusion defects, Uterine synechiae, Uterine fibroid
- Maternal medical illness: Cyanotic heart disease, Hemoglobinopathies
- Unexplained
C) Other: Premature ROM (Thrombophilias), Environmental (Smoking, Alcohol, Contraceptives, Drugs, Radiation)
Mechanisms of Spontaneous abortion:
- Before 8 weeks: Ovum surrounded by villi with decidual covering is expelled out
- 8-14 weeks: Expulsion of fetus leaving behind placenta and membranes
- Beyond 14 weeks: Expulsion of fetus followed by expulsion of placenta after varying interval
Pathology:
- Hemorrhage into deciduas, followed by necrosis of tissue adjacent to bleeding
- If early: ovum detaches, simulating uterine contractions that result in its ovulation
- Blighted ovum: Absence of fetal pole in gestational sac with diameter 3 or more (USG)
- Later abortion: fetus may undergo maceration
- Fetus compressus: Amniotic fluid is absorbedà fetus may become compressed and dessicated
- Fetus papyraceous: Fetus become so dry and compressed that it resembles parchment
Types: TICMICS
| Type | Description | Diagnosis | Treatment |
| Threatened | Miscarriage has started but recovery is possible
|
Os is closedUSG is normal | Pelvic rest for 1-2 days with gradual resumption of activities but abstinence from coitus and douchingDiazepam analgesic |
| Inevitable | Progressed to irrecoverable state
|
Os is open +/- ROMPOC felt through open os | Bleeding control with methergin 0.2mg<12 wks: D+C or Suction evacuation
>12 wks: Oxytocin |
| Complete | All POC expelledPain ceases
Spotting may be +nt |
Os is closedUSG shows empty uterus
Uterus small for duration of amenorrhea |
D+C if increased likelihood that abortion was incomplete |
| Incomplete | Some POC expelledMild cramping and bleeding
Visible tissue in vagina or endocervical canal |
Os is openUSG reveals retained fetal tissues | Hemodynamic stabilityEvacuation of Retained Products of Conception (ERCP i.e. D+C)
OR Tab. Misoprostol 200ug vaginally ever 4hrs |
| Missed | Pregnancy has ceased to develop
|
Os is closedUSG reveals no fetal cardiac activity
Fetal tissue is retained |
<12 wks: Expectant or Misoprostol 800mg vaginally repeated after 24 hrs if needed or Suction evacuation or D+C>12 wks: Misoprostol, Oxytocin, D+C |
| Septic | Infection of uterus and uterine contents with abortionEndometritis → Septicemia
Maternal mortality 10-15%
|
Cervical/High vaginal swab
Blood: Hb, TLC, DLC, ABO, Rh, culture, electrolytes, coagulation profile Urinanalysis USG CXR and AXR |
HospitalizationIV antibiotics
Complete uterine evacuation D+C |
| Recurrent | = or > 3 cosecutive miscarriageIf early, often due to chromosomal abnormalities à karyotyping of both parents
Incompetent cervix should be suspected with a history of repeated midtrimester painless cervical dilation and escape of liquor followed by painless expulsion of POC |
Cervical cultures for gonococcus, Chlamydia, group B streptococcus
Evaluate for uterine abnormalities |
Management of Cervical incompetence:Circlage operation
Restriction of activities |
