Miscarriage, spontaneous abortion (mechanism of disease)

ERRATA:
The box labeled "Maternal smoking and/or drugs" should be labeled blue, representing "Environmental / toxins"
The box labeled "Iatrogenic / unknown" should read "Idiopathic / unknown"
This is a flow chart on miscarriages (also called spontaneous abortion), covering the definition, etiologies, and manifestations.
ADDITIONAL TAGS:
Risk factors / SDOH
Cell / tissue damage
Hereditary / genetic
Miscarriage
Medicine / iatrogenic
Infectious / microbial
Biochem / metabolic
Immunology / inflammation
Signs / symptoms
Tests / imaging / labs
Environmental / toxins
Reproductive pathology
Uterus / cervix
Definition
Etiology
Manifestations
Miscarriage, aka spontaneous abortion: loss of pregnancy before 20 weeks' gestation.
Threatened abortion
Inevitable abortion
Missed abortion
Incomplete abortion
Complete abortion
x
x
x
x
or
Uterus
+/- POC:
products of
conception
+/- bleeding
Cervical os
Fetal activity
bleeding
activity
Reversible
Closed os
Intrauterine POC
bleeding
+/- activity
Irreversible
Open os
Visible / palpable POC
bleeding
No activity
Irreversible
Open os
Uterus or cervical canal POC
bleeding
No activity
Irreversible
Closed os
Extrauterine POC
No bleeding
No activity
Irreversible
Closed os
No expulsion of POC
TVUS: confirms +/- uterine bleeding; +/- fetal cardiac motion; abnormalities of yolk or gestational sac
Pelvic exam: visualize cervix; +/- vaginal bleeding
Downtrending β-hCG
Loss of pregnancy after
20 weeks is called stillbirth
Abnormal maternal reproductive organs:
Septate uterus
Uterine leiomyomas
Uterine adhesions
Cervical incompetence
Maternal systemic diseases:
Diabetes mellitus
Hyper/hypothyroidism
Infections
Hypercoagulation (antiphospholipid synd)
Fetoplacental:
50%: chromosomal abnormalities
Congenital anomalies
Anembryonic pregnancy (sac, no embryo)
Trauma
Maternal smoking and/or drugs
Amniocentesis, chorionic villus sampling
Idiopathic
/ unknown