dc.contributor.author |
Dias, T. |
en_US |
dc.contributor.author |
Mahsud-Dornan, S. |
en_US |
dc.contributor.author |
Thilaganathan, B. |
en_US |
dc.contributor.author |
Papageorghiou, A. T. |
en_US |
dc.contributor.author |
Bhide, A. |
en_US |
dc.date.accessioned |
2014-10-29T09:28:34Z |
|
dc.date.available |
2014-10-29T09:28:34Z |
|
dc.date.issued |
2010 |
en_US |
dc.identifier.citation |
British Journal of Obstetrics and Gynaecology. 2010; 117(8): pp.979-84 |
en_US |
dc.identifier.issn |
1470-0328 (Print) |
en_US |
dc.identifier.issn |
1471-0528 (Electronic) |
en_US |
dc.identifier.uri |
http://repository.kln.ac.lk/handle/123456789/1982 |
|
dc.description |
Indexed in MEDLINE |
|
dc.description.abstract |
OBJECTIVE: The aim of this study was to assess the performance of validated singleton crown-rump length (CRL) formulae in dating twin pregnancies at 11-14 weeks of gestation. DESIGN: Retrospective cohort study. SETTING: Fetal medicine unit of a London teaching hospital. SAMPLE: Three hundred and eighty-four pregnancies with known dates of conception. METHODS: Retrospective analysis of 266 singletons and 118 twin pregnancies conceived by in vitro fertilisation (IVF), with a known date of conception. The gestation calculated from the date of conception was compared with the expected gestation from fetal size using a number of different CRL formulae.
MAIN OUTCOME MEASURES: Difference in gestational age computed from fetal size (CRL) of the bigger and smaller fetus in twin pregnancies and singleton pregnancies using three formulae. RESULTS: Two of the three studied CRL formulae systematically underestimated the mean gestational age and size of singleton IVF pregnancies (Robinson formula: gestation = 1.4 days, size = 2.7 mm). Twin CRL measurements straddled those of singletons, regardless of the CRL formula used (Robinson formula: larger twin gestation = 2.4 days, size = 4.7 mm; smaller twin gestation = 0.8 days, size = 1.7 mm). These underestimates in gestation and size for IVF singleton and twin pregnancies are well within the known limits of accuracy of first = trimester ultrasound measurements, and are of limited clinical significance. CONCLUSIONS: Currently available CRL charts underestimate both the age and size of IVF singleton pregnancies by a clinically insignificant amount. This difference is similar for twin pregnancies, suggesting that singleton CRL charts can be used to date twin pregnancies accurately. |
en_US |
dc.publisher |
Wiley |
en_US |
dc.subject |
Pregnancy, Twin |
en_US |
dc.title |
First-trimester ultrasound dating of twin pregnancy: are singleton charts reliable? |
en_US |
dc.type |
Article |
en_US |
dc.identifier.department |
Obstetrics and Gynaecology |
en_US |
dc.creator.corporateauthor |
Royal College of Obstetricians and Gynaecologists (Great Britain) |
en_US |