Placenta Accreta SpectrumRisk and Diagnosis

September 22, 2018

DisclosuresNone*

*I support Medicaid Expansion in UT

Placenta Accreta Spectrum DisordersAGENDA / OBJECTIVES• What is it?• Who is at risk?• How is it diagnosed?• What should I do about it?

Placenta Accreta

Clinical definitionPlacenta that is abnormally adherent to the uterus

Placenta Accreta

Pathological definitionDirect attachment of the placental trophoblast to the uterine myometrium, with no intervening decidual or basalis layer

Placenta Accreta

Practical definitionA placenta that doesn’t detach and, when ripped off, causes massive life threatening bleeding.

Terminology Potpourri• Creta• Accreta• Accreta spectrum• Placenta accreta spectrum

disorder(s)• Morbidly adherent placenta• Accreta/Increta/Percreta• Abnormally invasive placenta

• Abnormally adherent placenta• Retained placenta• Focal accreta• Occult accreta

Pathophysiology• Absence or deficiency certain

layers of the uterine decidua• Failed remodeling of the

endometrium after cesarean• Histology: direct trophoblastic

‘attachment’ to myometrium• Placenta does not separate

bleeding

Invasion or Spreading?

Incidence

1960s 80s-90s 2000s

1 in 30,0001 in 2,510

1 in 533

Miller et al., AJOG 1997;177:210 Wu et al., AJOG 2005;192:1458

Top 10 Reasons for the Epidemic1. Cesarean sections2. Cesarean sections3. Cesarean sections4. Cesarean sections5. Cesarean sections6. Cesarean sections7. Cesarean sections8. Cesarean sections9. Cesarean sections10. Some other trends or contributors we don’t understand well

Cesarean and Accreta Risk

3.3%

10.8%

40.3%

60.6%66.7% 66.7%

0.2% 0.3% 0.6% 2.1% 2.3%6.7%

1 CS 2 CS 3 CS 4 CS 5 CS 6+ CS

If PreviaAll pregnancies

Risk

of A

ccre

ta

Silver et al., Ob Gyn 2006;107:1226

Cesarean Rates

12%

Which pregnant women are at risk?

Multiple cesareans + PreviaCesarean + PreviaOther *Uterine SurgeryCesarean + LLP?Any suspicious findings on outside US

*Uterine SurgeryMyomectomy

AblationSeptum takedown

IVF?Ashermans

Prior focal accretaPrior D&C for retained placenta

DiagnosisDepends on several things

1. Awareness of the problem2. Low index of suspicion3. Referral of at-risk women to Accreta referral centers4. Experienced radiology/MFM