[Show abstract][Hide abstract] ABSTRACT: To study the correlation of discrepancy between crown-rump length (CRL) and nuchal translucency (NT) in monochorionic twins at 11-14 weeks of gestation and subsequent development of twin-to-twin transfusion syndrome (TTTS) and selective fetal growth restriction (sFGR).
Retrospective cohort study.
Tertiary-care Fetal Medicine Unit, London.
Monochorionic twin pregnancies with known outcome.
Inter-twin discrepancy was calculated as a percentage of the larger CRL and smaller NT and compared among those developing TTTS, those with sFGR and those with normal outcome. Receiver operating characteristic (ROC) curves were constructed to evaluate the performance of inter-twin discrepancy in prediction of sFGR and TTTS.
Development of TTTS and sFGR.
A total of 242 monochorionic twin pregnancies were studied (102 TTTS, 36 sFGR and 104 controls). The median CRL discrepancy in the sFGR group (11.9%) was significantly higher (P < 0.001) than in the TTTS group (3.8%) and control group (3.5%). Median inter-twin NT discrepancies were not significantly different (P = 0.869) between sFGR and both TTTS and control groups (15.6%, 16.7% and 14.8%, respectively). Discrepancy in CRL performs well as a screening test for sFGR (area under ROC curve = 0.89), but not for TTTS (area under ROC curve = 0.58).
First-trimester CRL discrepancy in monochorionic twins is a marker for subsequent development of sFGR rather than TTTS. Inter-twin NT discrepancy does not appear to be significantly different in these two groups from those with normal outcome.
BJOG An International Journal of Obstetrics & Gynaecology 03/2012; 119(4):417-21. DOI:10.1111/j.1471-0528.2011.03250.x · 3.45 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A previous study suggested that the lower uterine artery pulsatility index (PI) is a better predictor of pre-eclampsia than is either the mean or higher indices. The aim of this study was to assess the relative value of these three indices for the prediction of pre-eclampsia in the first trimester of pregnancy.
This was a prospective study of 6221 singleton pregnancies. Uterine artery PI was obtained at the time of the 11-14-week nuchal translucency scan and receiver-operating characteristics curves for the lower, mean and higher PI value of the two uterine arteries in the prediction of pre-eclampsia were calculated.
There were 178 cases of pre-eclampsia. The associations between uterine artery PI and pre-eclampsia were stronger for early (requiring delivery < 34 weeks' gestation) and preterm (requiring delivery < 37 weeks) pre-eclampsia compared to pre-eclampsia at any gestation. There was no significant difference in the strength of the association between lower, mean and higher PI for pre-eclampsia at any gestation.
First-trimester uterine artery PI is strongly associated with the development of early and preterm pre-eclampsia. Lower, mean and higher uterine artery PIs are comparable in screening for pre-eclampsia. Any differences that exist between the lower, mean and higher uterine artery indices are unlikely to have a significant impact on screening sensitivities.
Ultrasound in Obstetrics and Gynecology 05/2011; 37(5):534-7. DOI:10.1002/uog.8848 · 3.85 Impact Factor