Prenatal sonographic signs of possible fetal genital anomalies

The sonographic markers of female and male external genitalia have been documented in early and late gestation. The aim of the present study was to report our experience of possible sonographic markers of fetal genital anomalies. Sonography was performed with a vaginal probe in early gestation and an abdominal sector scanner in advanced gestation. The following genital anomalies were observed: hypospadias, epispadias, ambiguous genitalia, and testicular feminization or Smith-Lemli-Opitz syndrome. It is therefore concluded that prenatal diagnosis of some genital anomalies is now possible.     

Maternal serum biochemical markers in pregnancies with fetal parvovirus B19 infection

Hydrops fetalis and fetal death caused by fetal parovirus B19 infection have been reported to be associated with elevated maternal serum alpha-fetoprotein (AFP), based on a total of six cases. It has been suggested that the absence of AFP elevation may be reassuring. Maternal serum levels of the Down syndrome screening markers unconjugated oestriol and human chorionic gonadotropin in cases of fetal parvovirus infection have not been previously reported. We report four cases of hydrops fetalis and fetal death caused by fetal parvovirus infection, each with unremarkable second-trimester levels of AFP, unconjugated oestriol, and human chorionic gonadotropin.     

Is fetal gender a risk factor for severe congenital cytomegalovirus infection?

Cytomegalovirus is the main cause of congenital viral infection and amniotic fluid viral load appears to be the single nonclinical prognostic factor. However, as in other infectious diseases, host genetics may influence the severity of the disease. To test this hypothesis, we looked retrospectively at the fetal gender in cases of severe congenital cytomegalovirus infection in our database. We also analyzed the international English literature covering this subject between 1985 and 2003. The proportion of females with brain abnormalities was statistically different from that of males (62/258: 24% vs 30/251: 12%, p = 0.004). The risk of abnormal brain development in infected fetuses was twice as high in females than in males (Chi² = 8.7; OR = 2, IC [1.26–3.21]). In our cases, amniotic fluid CMV DNA load was not significantly higher in males than in females (p = 0.06) and was also similar in severely and non-severely infected fetuses (p = 0.09). Copyright © 2005 John Wiley & Sons, Ltd.     

Short communication the natural history of fetal cytomegalovirus infection as assessed by serial ultrasound and fetal blood sampling: A case report

A patient in whom intrauterine fetal cytomegalovirus (CMV) infection was diagnosed at approximately 25 weeks' gestation is presented. The fetus was evaluated by serial fetal blood samplings and ultrasound examinations. The fetus manifested evidence of severe thrombocytopenia and hepatic inflammation, with recovery over a period of approximately 8 weeks. The initial sonographic findings of marked fetal ascites and cardiomegaly gradually resolved; ventriculomegaly developed during the third trimester. At delivery, the baby was morphologically normal with the exception of mild ventriculomegaly. Cord blood was negative for CMV IgM but urine was culture-positive for CMV. At age 3, the child has a severe but stable unilateral hearing deficit and is otherwise developmentally normal. This case demonstrates the utility of serial ultrasound and fetal blood sampling in the prenatal diagnosis and management of fetal CMV infection.     

Prenatal ultrasonographic diagnosis of fetal cerebral ventriculitis associated with asymptomatic maternal cytomegalovirus infection

Cytomegalovirus is the most common cause of congenital viral infection. In utero infection is usually suspected in patients with growth-retarded fetuses or when maternal illness precipitates serological investigations. A case is presented where routine ultrasound examination at 30 weeks' gestation in an asymptomatic patient demonstrated mild fetal ventriculomegaly. Transvaginal ultrasound enabled the visualization of intraventricular adhesions and small periventricular cysts. The suspected diagnosis of in utero cytomegalovirus infection was confirmed by the presence of IgM antibodies in fetal blood and subsequently by isolation of the virus from the infant's urine. The presence of mild fetal ventriculomegaly should prompt transvaginal brain imaging.     

Prenatal detection of rubella-specific IgM in fetal sera

Serum specimens were obtained by fetoscopy at 19–25 weeks' gestation from four fetuses whose mothers had had confirmed rubella earlier in pregnancy. They were tested for rubellaspecific IgM by antibody capture radioimmunoassay. No specific IgM was detected in one fetus and a healthy infant was delivered at term. Specific IgM was detected in the other three fetuses. In one case the level was low (1 unit) and this pregnancy went to term resulting in a neonate with clinical and laboratory evidence of congenital rubella infection. The remaining two fetuses had 2.8 and 2.4 units of specific IgM and the pregnancies were terminated. Blood obtained from these two fetuses after abortion showed levels of 5.4 and 2.9 units respectively. No specific IgM was detected in sera from eleven other fetuses aborted because of maternal rubella but five of these cases were terminated before 19 weeks and in five the interval between rash and abortion was three weeks or less. The results show that the human fetus can produce detectable specific IgM antibody by 19–20 weeks' gestation after exposure to rubella sevella several weeks earlier. However, a larger study is required to define the reliablity of fetoscopic blood sampling for the diagnosis of intrauterine infection.     

Intraventricular haemorrhage in a fetus with cerebral cytomegalovirus infection

Cytomegalovirus (CMV) is the leading infectious cause of prenatal neurological damage, which is particularly severe when primary maternal infection occurs during the first 16 weeks of gestation, at the time of organ development and neuronal migration. Vascular involvement has been suggested to be among thepossible pathogenic mechanisms of virus-induced pathology, in addition to direct viral effects. We report on a fetus with cerebral CMV infection, which had intraventricular haemorrhage, together with oligohydramnios and hyperechogenic bowel, following maternal primary CMV infection. Copyright © 2002 John Wiley & Sons, Ltd.     

Promises and pitfalls of first trimester sonographic markers in the detection of fetal aneuploidy

First trimester sonographic markers are the only markers achieving detection rates above 50% in the prenatal detection of fetal aneuploidy. Although potentially they are the best markers, some concerns have arisen about its clinical application. Pitfalls may be due to inability to examine the markers, incorrect assessment, or incorrect interpretation of the findings. Markers may be unable to be examined due to maternal (maternal body habitus, previous surgery) or fetal reasons (incompatible fetal position or fetal movements). Causes of incorrect interpretation may be insufficient image magnification, incorrect caliper placement (nuchal translucency), incorrect insonation angle (nasal bone), venous contamination (ductus venosus), or arterial contamination (tricuspid regurgitation), among others. Venous contamination in ductus venosus waveforms may mimic an abnormal blood flow when it is normal, and the opposite can also occur. Finally, incorrect interpretation of a substantially increased nuchal translucency may lead to a false impression of an ominous fetal prognosis or may be confounded with a cystic hygroma. Copyright © 2008 John Wiley & Sons, Ltd.     

Cardiotocographic and sonographic findings in two cases of antenatally diagnosed intrauterine fetal brain death

Intrauterine fetal brain death is a rare cause of a fixed fetal heart rate pattern. Seven cases have been previously reported in the literature, but only two of them were diagnosed prenatally and all the newborns died soon after delivery. Two additional cases of antepartum diagnosis of intrauterine fetal brain death, managed expectantly, are reported. We had the unique opportunity to document progressive sonographic cerebral changes during the follow-up period, following the neurological event, while the fetus continued life and growth in utero. The cardiographic and sonographic findings suggesting intrauterine fetal brain death were a prolonged fixed fetal heart rate, even following a vibroacoustic and contraction stress test; an atonic fetus without breathing and body movement; and the appearance of hydramnios and the development of ventriculomegaly.     

Maternal serum alpha-fetoprotein levels and fetal outcome in early second-trimester oligohydramnios

Early second-trimester oligohydramnios was associated with normal maternal serum alpha-fetoprotein (MSAFP) levels in nine out of 26 cases (35 per cent). Congenital malformations of the fetal urinary tract resulting in fetal anuria were present in nine cases; in seven of them, normal MSAFP levels were measured. In contrast, normal MSAFP levels were established in only 2 out of the 17 cases without fetal malformations. These data suggest that fetal urine is the major source of elevated AFP in the maternal compartment in early second-trimester oligohydramnios. This is further supported by the lack of any relationship between concentrations of MSAFP non-reactive with Concanavalin A, originating mainly from the yolk sacderived amniotic fluid AFP pool, and the presence of fetal diuresis. Three out of 26 women had experienced early second-trimester oligohydramnios in a previous pregnancy, suggesting the existence of a recurrence risk for this condition.     

Maternal serum thyroid antibodies in early pregnancy and fetal Down's syndrome

Thyroid antibodies were measured in mid-trimester antenatal serum samples from 77 pregnancies affected by fetal Down's syndrome and 385 unaffected control pregnancies. Using a haemagglutination technique, thyroglobulin antibodies were detected in 5·2 per cent of cases (4) and 2·9 per cent of controls (11), and thyroid microsomal antibodies were detected in 22 per cent (17) and 15 per cent (59), respectively. Using an enzyme-linked immunosorbent assay (ELISA) for thyroglobulin antibodies and a cut-off level of 50 KIU/1, positive results were found in 25 per cent of cases (19) and 22 per cent of controls (84). Using an ELISA for thyroid microsomal antibodies and the same cut-off level, the proportions were 52 per cent (40) and 39 per cent (149), respectively. While not statistically significant, the differences were consistent with the previously reported increased levels of thyroid antibody found in nonpregnant women who had had pregnancies associated with Down's syndrome.