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Ultrasound Growth Plotting


I am in contact with a mom who is pregnant with her first child following the birth of her child with CdLS. She is quite nervous about possible outcomes. A recent ultrasound, performed at 20 weeks, 5 days noted all limbs present and intact but that fetus was measuring as one week early (19 weeks, and 5 days). Doctor told her not to worry but she obviously is concerned. Her next ultrasound is in 4 weeks. Should any steps be taken before then?

Answer of our experts

Usually these measurements are assessed relative to earlier ultrasound measurements or to the last menstrual period. Earlier use measurements are the most helpful and accurate. LMP (last menstrual period) dating is often very inaccurate. It is unlikely that a growth abnormality could be detected this early in CdLS; growth problems usually do not become apparent before 25 weeks. So, the obstetrician is probably right...this is unlikely to be significant. He should, however, be sure the cerebral ventricles, upper limbs, face, hands, and feet are normal.

MK/ TK 7-13-10

Response: PAPP-A has also been recommended during the first trimester as a screening maternal blood test.

TK 7-13-10

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Find other pages that share the same topic as this page diagnosis of CdLS prenatally (before birth)


diagnosis of CdLS prenatally (before birth)

If a prenatal ultrasound scan (sonography) detects features consistent with CdLS, possibilities for prenatal genetic testing should be discussed with the parents.
If a causative gene change has been detected in an earlier child or pregnancy, reliable prenatal diagnostic testing should be discussed with the family. Targeted variant testing can be performed using DNA derived from the placenta or amniotic fluid.

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