Cost-effectiveness in establishing hemophilia carrier detection and prenatal diagnosis services in a developing country with limited health resources.

The cost-effectiveness of carrier detection and prenatal diagnosis for hemophilia at the International Hemophilia Training Center, Bangkok, Thailand was studied. From 1991 to 2002, 209 females from 124 families with hemophilia A and B were included. There were 180 hemophilia A carriers and 29 hemophilia B carriers which could be classified into 78 obligate and 131 possible carriers. The phenotypic analysis for possible carriers involved the determination of levels of factor VIII or IX clotting activity (FVIII:C, FIX:C) and the ratio of FVIII:C and von Willebrand factor antigen. The result revealed that 49 females (37.4%) were diagnosed as carriers, 65 females (49.6%) were normal and 17 females (13%) were undetermined. Additional genotypic analysis was provided to 46 families with 74 females with obligate, proven or undetermined carriers within the reproductive life. The polymorphisms associated with factor VIII and IX genes were used including Bcl I for the factor VIII gene and combined use of Mse I, Sal I, Nru I, Hha I and Dde I for the factor IX gene. The informative rate was 59.4% (44/74). Consequently, 12 prenatal diagnoses for fetus at risk were performed. Sex determination was initially determined and followed by the diagnosis of hemophilia through informative gene tracking and/or the measurement of fetal levels of FVIII:C or FIX:C. The result revealed that 3 male fetuses were affected. The total cost of carrier detection and prenatal diagnosis that the families had to pay in the government hospital was 238,600 Baht (US dollars 5,965). It was compared to the estimated cost of minimal replacement therapy using lyophilized cryoprecipitate for the survival time of 30 years in one patient with hemophilia of 1,012,500 Baht (US dollars 25,312.5). The cost of prevention was much less than the replacement therapy. In conclusion, it is cost-effective to establish the service for carrier detection and prenatal diagnosis for hemophilia especially in developing countries with limited health resources.

Nuchal translucency in normal fetuses in a Thai population.

The purpose was to study nuchal translucency thickness of normal Thai fetuses in the first trimester. From January 1996 to June 1999, there were 1,970 pregnant women, whose gestational ages were between 10 to 13(+6) weeks of gestation, who attended the Down syndrome screening clinic. Nuchal translucency (NT) thickness measurement was used as the screening method for Down syndrome. When the result showed an increased risk for Down syndrome, the patient was counselled and the invasive test for the definite diagnosis was optional. Pregnant women who had had an abortion and/or congenital anomaly babies were excluded. Only pregnant women who had normal newborns were recruited in this study. There were 1,631 pregnant women who had normal newborns in this study. The mean maternal age was 28.70 +/- 5.14 years. There were 222 (13.6%) pregnant women whose ages were more than or equal to 35 years. There was quadratic correlation of an increase in nuchal translucency and the crown-rump length (CRL) in normal fetuses in the first trimester. The quadratic equation was log10 NT = 1,215 x 10(-4) CRL-8.7 x 10(-4) CRL(2)-3.7037. The normal fetuses with nuchal translucency thickness more than or equal to 2.5 mm were found in 1.23 per cent in this study. In conclusion, there was quadratic correlation of nuchal translucency thickness and crown-rump length of first trimester fetuses in a Thai population.