Echogenic intracardiac focus: a sonographic sign for fetal Down syndrome.

Objective: To determine whether an echogenic intracardiac focus identified in the second-trimester fetus is related to an increased risk of Down syndrome.

Methods: During a 10-month period, all women with singleton gestations who underwent second-trimester genetic amniocentesis for non-imaging indications were evaluated prospectively by prenatal sonography. The presence or absence of an echogenic intracardiac focus was noted.

Thickened nuchal fold in fetuses not at risk for aneuploidy.

Many studies have shown that a thickened nuchal fold in a second-trimester fetus is a sonographic sign suggestive of a high risk for Down syndrome. These series have included fetuses already at risk for aneuploidy because of advanced maternal age or abnormal maternal serum alpha-fetoprotein (AFP) levels. The authors describe the sonographic and karyotypic findings in 42 women younger than age 35 years whose fetuses were noted to have a thickened nuchal fold.

Small sac size in the first trimester: a predictor of poor fetal outcome.

A nonbradycardiac fetal heart rate is associated with a low rate of spontaneous abortion (2%-4%). To determine criteria for predicting impending first-trimester loss when a normal fetal heart rate is identified sonographically, the authors studied 16 consecutively examined patients with pregnancies of 5.5-9 weeks gestation, a small sac size, and fetuses with normal cardiac activity.

Can sonographers reliably identify anatomic features associated with Down syndrome in fetuses?

To standardize femur measurement for the identification of fetuses at risk for Down syndrome, sonographers of varying professional experience and background measured the femurs of 20 Down syndrome fetuses and 709 normal control fetuses. A regression analysis performed to compare biparietal diameter to femur length on the 709 control fetuses yielded the following formula: expected femur length = -9.3105 + 0.

First trimester bradycardia. A sign of impending fetal loss.

Normal first trimester fetal heart rates rise from an average of 100 beats per minute (bpm) at 5 to 6 weeks to 140 bpm at 8 to 9 weeks. The heart rates of 65 consecutive first trimester fetuses between 5+ and 8+ weeks were measured to determine whether unusually slow first trimester fetal heartbeats are associated with a poor outcome. All five pregnancies in which heart rates were below 85 ended in spontaneous miscarriage.

Cyst of the fetal choroid plexus: a normal variant?

Cysts of the choroid plexus have been identified ultrasonographically in second-trimester fetuses and usually have regressed by 24 weeks' gestation. Choroid plexus cysts have been linked with trisomy 18, and this possible association has prompted a review of our experience. Choroid plexus cysts were seen ultrasonographically in 38 consecutive fetuses between 15 and 28 weeks' gestation.

Sonographic diagnosis of Down syndrome in the second trimester.

We report a sonographic sign consisting of increased skin or soft tissue thickening at the back of the fetal neck during the second trimester, which correlates well with the diagnosis of Down syndrome. Eight hundred consecutive sonograms were performed in conjunction with genetic amniocentesis where four fetuses had trisomy 21 (Down syndrome) by karyotype. Two or 50% had sonographic findings consistent with Down syndrome.

A sonographic sign for the detection in the second trimester of the fetus with Down's syndrome.

Sonographic structural surveys were made at the time that 904 amniocenteses were performed for genetic evaluation in the second trimester. A sonographic sign was identified which places the fetus at high risk for having Down's syndrome.