Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-26T07:35:17.974Z Has data issue: false hasContentIssue false
  • English
  • Français

Two Corpora Lutea Seen at 6–13 Weeks' Gestation Infers Dizygosity Among Spontaneous Same-Sexed Dichorionic Twins

Published online by Cambridge University Press:  21 February 2012

Jean Woo ,
Stephen Tong ,
Megan J. Campbell ,
Leanne Wallace ,
Simon Meagher ,
Grant W. Montgomery ,
Fay Chao ,
Weng Chan  and
Beverley Vollenhoven
Jean Woo
Affiliation:
Southern Health, Women's and Children's Program, Victoria, Australia.
Stephen Tong*
Affiliation:
Southern Health, Women's and Children's Program, Victoria, Australia; Department of Obstetrics and Gynaecology, Monash University, Victoria, Australia; Monash Ultrasound for Women, Monash IVF, Epworth Hospital, Richmond, Victoria, Australia. [email protected]
Megan J. Campbell
Affiliation:
Molecular Epidemiology Group, Queensland Institute of Medical Research, Brisbane, Australia.
Leanne Wallace
Affiliation:
Molecular Epidemiology Group, Queensland Institute of Medical Research, Brisbane, Australia.
Simon Meagher
Affiliation:
Monash Ultrasound for Women, Monash IVF, Epworth Hospital, Richmond, Victoria, Australia.
Grant W. Montgomery
Affiliation:
Molecular Epidemiology Group, Queensland Institute of Medical Research, Brisbane, Australia.
Fay Chao
Affiliation:
Southern Health, Women's and Children's Program, Victoria, Australia.
Weng Chan
Affiliation:
Southern Health, Women's and Children's Program, Victoria, Australia.
Beverley Vollenhoven
Affiliation:
Southern Health, Women's and Children's Program, Victoria, Australia; Department of Obstetrics and Gynaecology, Monash University, Victoria, Australia.
*
*Address for correspondence: Dr Stephen Tong, Department of Obstetrics and Gynaecology, Monash Medical Centre, 246 Clayton Rd., Clayton 3168, Victoria, Australia.

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Current ultrasound techniques can accurately determine the chorionicity of twins, but not zygosity. We previously proposed that the zygosity of spontaneously conceived twins can be determined at early ultrasound, where 2 corpora lutea infers dizygosity, and 1 implies monozygosity. Here we did a case series, comparing zygosity predicted using this method with definitive DNA genotyping of twins after birth. We retrospectively identified 14 ultrasound reports of spontaneous twin pregnancies at 6(+0 days) to 13+6 weeks' gestation, where both ovaries were seen and the number of corpora lutea documented. We visited all twin pairs, obtained buccal smears, and determined zygosity by genotyping 9 independent microsatellite markers. All 8 cases where 2 corpora lutea were seen were dizygotic pregnancies. One further case where 3 corpora lutea were seen was also dizygotic. All 3 sets of monozygotic twins had 1 corpus luteum. There were 2 cases incorrectly assigned, where 1 corpus luteum was seen in dizygotic pregnancies. We conclude if 2 corpora lutea are seen at a first trimester ultrasound of spontaneously conceived dichorionic twins, they appear to be almost certainly dizygotic. However, if 1 corpus luteum is seen in dichorionic twins, zygosity cannot be determined with certainty since it is either monozygotic, or dizygotic where a second corpus luteum has been missed.

Keywords

Zygosityultrasoundchorionicitytwinscorpus luteum
Type
Articles
Information
Twin Research and Human Genetics , Volume 12 , Issue 2: SPECIAL SECTION: Genes for Health Meeting 2009 , 01 April 2009 , pp. 180 - 182
Copyright
Copyright © Cambridge University Press 2009