Miscarriage - Bashiri

Question 1

What are associated factors to increased miscarriage?

Answer 1

Mother age.
No previous full-term normal pregnancy.
Previous spontaneous abortions.
A previous stillbirth
A previous infant with malformations or known genetic defects.
Parental influences, including balanced translocation carriers and medical complications.

Systemic and chronic diseases (TORCHeS)
Bicornuate or septate uterus
Previous scarring (Asherman’s)

Antigen related (Rh, ABO, HLA, etc.)

Smoking, alcohol, caffeine, drugs, other toxicities

Trauma (especially to the corpus luteum in the first 12 weeks)

Question 2

What percentage of miscarriages are abnormal karyotypes?

What is the most common aneuploidy?

Answer 2

In approximately 50% - abnormal karyotype.

This incidence decreases to 20-30% in second trimester losses, and 5-10% in third trimester losses.

Polyploidy in 20% of miscarriages

Turner’s (XO) is the most common aneuploidy causing miscarriage.

Question 3

What are the 5 types/stages of spontaneous abortion/miscarriage?

Answer 3

1. Threatened abortion
   Happens to at least 20% of women
   Cervix remains closed and mostly the pregnancy continues until the end of term
   Need to measure gestational age and heartbeat (risk increases with no heartbeat)
   Sometimes given progesterone but sent home
2. Inevitable Abortion
   Bleeding with open cervix
   Hospitalize and send to OR to evacuate uterus or wait and see
   May send home and if bleeding continues to come back
   Need a good PE to check if cervix is open
3. Incomplete Abortion
   Open cervix, bleeding and fetus is out but not all products of conception
   This is an emergency, bleeding can cause hypovolemic shock or death if uterus is not evacuated
4. Complete Abortion
   Passage of the entire conceptus
   Need to indicate that there is nothing left in the uterus with ultrasound
   May be mimicked by early threatened abortion or ectopic pregnancy
5. Missed abortion
   Fetus no longer has a heartbeat and calculated fetal age is older than appears in reality
   Pregnancy is not expelled for unknown reason
   Can cause DIC
6. Blighted Ovum
   Anembryonic pregnancy with only a gestational sac indicated failed development. Ultrasound diagnosis alone.

Question 4

What are the laboratory findings in a spontaneous miscarriage?

Answer 4

CBC
 Anemia (HgB most important to see blood loss), WBC and ESR elevated (even without infection)

Blood type, indirect Coombs (if mom Rh- give Rhogam for next pregnancy)

Plasma β-hCG (not used clinically except for early/ectopic)

Transvaginal ultrasound
Heartbeat and gestational age
Embryo or fetus without heart motion= missed abortion; abnormal gestational sac without embryo = blighted ovum

Question 5

What are the most common causes of recurrent pregnancy loss?

Answer 5

Unexplained (40-50%)
-Includes Thrombophilias that aren’t antiphospholipid syndrome

Autoimmune (20%)

Endocrine Factors (17-20%)

Anatomic factors (10-15%)

Genetic Factors (2-5%)

• Aneuploidy
• Most important before 10 weeks

Infections 0.5-5%