Dating ultrasound measurements
The Monash Chart, but none of the existing charts, accurately determined gestational age among an independent IVF twin cohort (185 twin pairs).
When applied to 3052 naturally-conceived singletons scans, The Monash Chart generated estimated due dates that were different to all existing charts ( all comparisons).
We examined CRL lengths at 6–9 weeks of gestation measured in a large IVF cohort where gestational age could be calculated from date of fertilisation.
We assessed the ability of six commonly used reference charts to accurately date these pregnancies.
All examinations were performed at three ultrasound centres that exclusively perform women’s health ultrasounds.
All ultrasounds were transvaginal, done on Advanced Technology Laboratories HDI 5000 ultrasound machines by experienced sonographers.
METHODS Urban areas in eight geographically diverse countries that met strict eligibility criteria were selected for the prospective, population…
For this retrospective database study where we used de-identified data in aggregate, the ethics committee specifically approved our request not to obtain individual patient consent.All charts generated dates significantly different to IVF dates ( all comparisons).Thus we generated a new reference chart, The Monash Chart, based on a line of best fit describing crown-rump length across 6 1 to 9 0 weeks of gestation (true gestational age) in the IVF singleton cohort.These were identified from a total cohort of 4971 first trimester ultrasound reports of IVF and naturally conceived pregnancy scans.Pregnancies that resulted from frozen embryos transfer, complicated by fetal structural anomalies, delivered before 24 weeks, or had missing data were all excluded.