Current practices in determining amnionicity and chorionicity in multiple gestations

Prenat Diagn. 2011 Jan;31(1):125-30. doi: 10.1002/pd.2663.

Abstract

Objective: To evaluate the accuracy of amnionicity and chorionicity (A/C) diagnosis of referral physicians and a tertiary care center as compared to histopathologic diagnosis.

Method: A retrospective study of 289 multi-fetal gestations was performed comparing A/C diagnoses of referring physicians, a tertiary care center, and histopathology.

Results: Two hundred and eighty-nine multi-fetal pregnancies were referred for evaluation; only 43.6% (126/289) carried an accurate diagnosis of A/C before tertiary care center evaluation. The tertiary care center accurately identified A/C in 94.8% (274/289) overall and 100% in first trimester twins and triplets. Referrals with an unspecified A/C diagnosis included 46.1% (113/245) twins and 64.1% (25/39) triplets.

Conclusion: Accurate diagnosis of A/C can be obtained by the early assessment of key sonographic findings. Referral providers are less accurate at determining A/C of multifetal gestation when compared to a tertiary center, suggesting that an emphasis should be placed on enhancing these diagnostic skills in the general community or encouraging referral when diagnosis is ambiguous.

MeSH terms

  • Adolescent
  • Adult
  • Amnion / diagnostic imaging*
  • Chorion / diagnostic imaging*
  • Female
  • Gestational Age
  • Humans
  • Middle Aged
  • Pregnancy
  • Pregnancy, Multiple*
  • Reproductive Techniques, Assisted
  • Retrospective Studies
  • Triplets
  • Twins
  • Ultrasonography, Prenatal / trends*