Incremental cost-effectiveness of incorporating oestriol evaluation in down syndrome screening programmes

As screening for Down syndrome becomes increasingly sophisticated, it is important to evaluate the newer technologies in terms of their cost-effectiveness. One recent addition to Down syndrome screening programmes is maternal serum unconjugated oestriol (uE₃), especially when used in conjunction with maternal serum α-fetoprotein and human chorionic gonadotropin. Using assumptions used in a California proposal to justify an expanded screening programme for Down syndrome, we calculated both the average and the incremental cost-effectiveness of adding uE₃. Using the base case assumptions, including an $8 fee for the uE₃, the incremental cost-effectiveness of adding uE₃ to the proposed California programme is $119 100 per case detected, a value that compares favourably with other Down syndrome screening programmes. The sensitivity analysis supports this conclusion over a wide range of assumptions. However, because of the uncertainty with some key data, it is still too early to fully support the inclusion of uE₃ in Down syndrome screening programmes.     

Prenatal diagnosis of inborn errors in peroxisomal β-oxidation

In recent years, an increasing number of inherited diseases in man have been recognized in which there is an impairment in the peroxisomal β-oxidation of very-long-chain fatty acids. In general, these disorders are associated with severe neurological and physical abnormalities and death within the first years of life. In this paper we describe our experience with regard to the prenatal diagnosis of a number of different inborn errors of peroxisomal β-oxidation. Eleven pregnancies at risk were monitored by measuring very-long-chain fatty acid levels as well as very-long-chain fatty acid β-oxidation in cultured chorionic villous fibroblasts and/or amniotic fluid cells. Five affected fetuses were identified. It is concluded that prenatal diagnosis in this group of diseases can be done reliably using cultured chorionic villous fibroblasts or amniotic fluid cells.     

Patients' attitudes following chorionic villus sampling

The attitudes of 190 patients who had undergone chorionic villus sampling (CVS) were assessed by means of a questionnaire. One hundred and fifty-two patients replied of whom 68 (45 per cent) were referred because of increased maternal age and in the other 84 cases the indications included previous chromosomal abnormalities, fetal sexing, DNA analysis, and biochemical analysis. One hundred and twenty-two patients had a transcervical procedure, 24 had a transabdominal, and six patients required both procedures. One hundred and forty-one patients (93 per cent) reported CVS to be a satisfactory procedure, and the same percentage thought earlier diagnosis was beneficial. Thirty-nine patients (81 per cent) reported a better experience with CVS than with a previous amniocentesis. A majority of patients (93 per cent) wished a CVS in a future pregnancy and 137 patients (97 per cent) would accept a risk of miscarriage from the procedure of twice that quoted for amniocentesis (1 per cent).     

Transvaginal chorionic villus sampling

Chorionic villus sampling (CVS) with either transcervical catheters or transabdominal needles is a widely-accepted method for prenatal diagnosis. However, there exists a small subset of patients in whom sampling is difficult or impossible with either route because of individual anatomic variations. A new method of chorionic villus biopsy has been developed to circumvent these problems, utilizing transvaginal chorionic needle aspiration guided by an intravaginal ultrasound probe. This technique was performed successfully in 15 patients in whom villi could not be obtained by either of the conventional methods. This method now makes CVS possible in essentially all women regardless of their uterine anatomy or placental placement; it may also prove useful for very early chorionic sampling.     

Microphthalmia–prenatal ultrasonic diagnosis: A case report

Prenatal real-time ultrasonographic diagnosis of microphthalmia is presented. Diagnosis was made at 18 weeks' gestation in a fetus of a patient with a previous infant affected with the syndrome of cryptophthalmia with absence of septum nasi and ambiguous genitalia (Fraser syndrome). Recognition of microphthalmia as a part of Fraser syndrome and the easy visualization of fetal facial bones and orbits in the second trimester made the diagnosis possible.     

Evidence of a second gamete fusion after the first cleavage of the zygote in a 47,XX, + 18/70,XXX, + 18 mosaic. A remarkable diploid-triploid discrepancy after CVS

A 70,XXX, +18 karyotype was found by chorionic villus sampling, while the fetal fibroblast culture of the affected fetus revealed a 47,XX,+ 18 karyotype. From several possible mechanisms, we assume that a second gamete fusion occurred after the first cell division of the zygote. According to this interpretation, the mosaicism arose in very early pregnancy (at the two-cell stage). This discrepancy can therefore be explained by selection pressure, due to the differentiation processes in the embryonic tissues.