Prenatal diagnosis of hemophilia by fetal blood sampling under ultrasound guidance

In utero fetal blood sampling was performed in 55 cases for prenatal diagnosis of hemophilia A and B. Fifteen fetuses were found to be affected. However, with this new procedure, it was possible to demonstrate that fetuses were not hemophiliacs in 40 cases. Therefore, pregnancy was not interrupted; these infants were born and definitely proven to be normal. There were no diagnostic errors.

Serum somatomedin C, bioassayable growth-promoting activity (thymidine activity), and transferrin in human fetuses: in utero study

Serum somatomedin C, thymidine uptake stimulating activity, and transferrin were measured in fetal blood collected by ultrasound-guided puncture of umbilical vessels in utero during prenatal assessment for mother-to-fetus transmissible infections. Serum somatomedin C and transferrin were measured by immunoassay. Thymidine activity was measured by assay of [3H]thymidine incorporation into lectin-activated human lymphocytes. Studies were conducted in 48 healthy fetuses at gestational ages 21-28 wk. From 21-24 to 25-28 wk, serum somatomedin C significantly increased from 0.05 +/- 0.06 to 0.24 +/- 0.03 U/ml, while thymidine activity significantly decreased from 1.41 +/- 0.15 to 0.95 +/- 0.06 U/ml. Transferrin levels did not change. These data suggest that the humoral control of fetal growth at midpregnancy involves mechanisms other than direct regulation by somatomedin.

Fetal blood sampling during pregnancy with use of a needle guided by ultrasound: a study of 606 consecutive cases

Because of various prenatal diagnoses, 606 fetal blood samplings were carried out in 562 pregnancies from the gestational week 17 to 38 with use of a 20-gauge needle guided by ultrasound. The procedure was performed on outpatients under local anesthesia and without medication before or after the procedure. Pure fetal blood was obtained at the first attempt in 588 cases. A second attempt was necessary in 18 cases. Maternal blood contamination was never present. Amniotic fluid dilution was noted in 15 cases. At the beginning of our experience only three cords could not be punctured. The duration of the procedure was less than 10 minutes in 90% of cases. Fifty-eight pregnancies were terminated after consideration of the results of the diagnosis, and 504 pregnancies were continued. The complications found in these pregnancies were premature delivery (5%), growth retardation (8%), in utero death (1.1%), and spontaneous abortion (0.8%). In the future this new procedure could replace fetoscopy and initiate an important field of new investigations.

Cortisol, cortisone and dehydroepiandrosterone sulfate levels in umbilical cord and maternal plasma between 21 and 30 weeks of pregnancy

Cortisol (F), Cortisone (E) and dehydroepiandrosterone sulfate (DHAS) were determined in maternal peripheral plasma and umbilical cord plasma between 21 and 30 weeks of amenorrhea. In fetal plasma, DHAS levels were the highest and those of F the lowest. E always exceeded F. The pattern of all these steroids was characterized by a plateau throughout the period considered. In maternal plasma, F levels were more elevated than those of E but lower than DHAS concentrations. All the steroids plateaued as in the fetus. The study of the correlation between the steroids in either the same milieu or in maternal and umbilical cord plasma demonstrated that fetal E was correlated with maternal F and with fetal F while fetal DHAS was inversely correlated with maternal E.

Direct fetal blood examination for prenatal diagnosis of homozygous familial hypercholesterolemia

Prenatal diagnosis of homozygous hypercholesterolemia was achieved at the 24th week of gestation by analysis of lipid values in a fetal blood sample obtained by a needle guided by ultrasound. These abnormal values were compared to values in blood obtained from normal fetuses at the same stage of gestation. After abortion, the diagnosis was confirmed by measuring LDL receptor activity on fibroblast cultures from a skin biopsy. The main advantages of this procedure over measuring LDL receptor activity on cultured amniotic cells are its simplicity and speed.

Serum somatomedin-C and bioassayable growth-promoting activity (thymidine activity) in appropriate and small-for-gestational-age human newborns

The serum level of radioimmunoassayable somatomedin-C and the bioassayable growth-promoting activity evaluated by the stimulating effect of serum upon thymidine incorporation into activated lymphocytes have been measured in the blood of term human foetuses. Comparison between those with a low birth weight and those with normal birth weight has shown that small-for-gestational-age subjects have lower somatomedin-C (0.31 +/- 0.03 vs 0.52 +/- 0.03) and thymidine activity (1.03 +/- 0.11 vs 1.50 +/- 0.07) (P less than 0.001). A positive correlation between somatomedin and thymidine activity was found. There was no difference in serum transferrin levels between both groups. It is suggested that somatomedin, and probably other growth-promoting factors measured by the thymidine bioassay, play a role in regulation of the foetal growth.

Free amino acids in human fetal plasma

Free amino acids were determined on fetal plasma samples in 28 pregnancies between 20 and 33 wk gestation. No correlation can be observed between these concentrations and the age of gestation.

Vitamin K dependent proteins in fetal hemostasis at mid trimester of pregnancy

The vitamin K dependent coagulation factor activities were measured in 63 normal human fetuses from 19 to 28 weeks of pregnancy. These activities were included between 9 to 28 percent of normal adult levels. Prothrombin antigen, factor IX antigen and protein C were also measured. There is a good correlation between prothrombin procoagulant activity and antigenicity, suggesting that low level of these vitamin K dependent proteins in fetuses is probably a consequence of liver immaturity.

Presence of an acid-labile alpha-interferon in sera from fetuses and children with congenital rubella

In congenital rubella an acid-labile alpha-interferon was present in sera collected from fetuses between weeks 21 and 29 of gestation and from children with active congenital rubella. This interferon was different from the interferon detected in normal amniotic fluid and was not found in sera from uninfected fetuses or from children with postnatally acquired rubella. The fetal interferon is of interest as a complementary marker to confirm the virus contamination of the fetuses during maternal rubella. The role of the prolonged synthesis of this interferon in congenital rubella disease and its immune defects are discussed.

Prenatal diagnosis of congenital toxoplasmosis

Prenatal diagnosis of congenital toxoplasmosis was attempted by means of fetal blood sampling at 20-24 weeks' gestation. It was possible to detect in fetal blood samples non-specific laboratory signs of fetal infection, specific antibodies of fetal origin (IgM), and parasitaemia by inoculation of the sample into mice. Amniotic-fluid samples were also inoculated into mice and parasites were often present when the fetus was infected. Ultrasound examination of the fetus was done repeatedly, mainly to detect any enlargement of the cerebral ventricles. Together the results of these examinations allowed a reliable diagnosis, which was confirmed by the presence of necrotic foci of toxoplasmic encephalitis in the fetus in every case. Only 1 case of congenital toxoplasmosis occurred among 209 cases with negative prenatal diagnoses.

Prenatal diagnosis of congenital rubella

In an attempt at prenatal diagnosis of fetal infection after primary rubella infection before 18 weeks of pregnancy fetal blood was taken by direct puncture under ultrasound guidance at 20-26 weeks of pregnancy from eighteen patients. Total IgM was assayed by radial immunodiffusion and rubella-specific IgM by IgM capture immunoassay. Rubella-specific IgM was detected in twelve of the eighteen fetuses. The parents decided whether to continue or terminate the pregnancy on the basis of the time of onset of maternal rubella. All six pregnancies in which rubella occurred before 12 weeks of gestation were terminated. Of the six with rubella after 12 weeks two were terminated. Among the six fetuses negative for rubella-specific IgM, five had no rubella-specific IgM at birth and no persistent IgG but one was found to be infected at birth; this false-negative diagnosis was due to sampling too early during pregnancy.

Fetal blood sampling during the third trimester of pregnancy

Fetal blood sampling was possible during the third trimester of pregnancy by direct puncture of the umbilical vein near its placental insertion, using a needle guided by ultrasound. Between 2 and 6 ml of pure fetal blood were obtained from three pregnancies without adverse effect on the fetuses. If this new procedure proves to have an acceptable complication rate it should widen the field of prenatal diagnosis for the detection of treatable diseases of the fetus.

Plasma human chorionic somatomammotropin deficiency in a normal pregnancy is the consequence of low concentration of messenger RNA coding for human chorionic somatomammotropin

Human chorionic somatomammotropin (hCS) is important in the hormonal monitoring of human pregnancies. Presented is the case of a clinically normal pregnancy in which a very low plasma level of hCS was detected. The concentration of messenger ribonucleic acid (mRNA) coding for hCS was evaluated to determine the level on which the deficiency occurred.

Fetal blood sampling via the umbilical cord using a needle guided by ultrasound. Report of 66 cases

Pure fetal blood has been aspirated in utero from the umbilical vein near the placental insertion of the cord using a twenty gauge needle under ultrasound guidance. Sixty-six samples were taken on 63 pregnancies between 17 and 32 weeks of gestation. One to two millilitres of blood can be obtained easily without amniotic fluid dilution or contamination by maternal blood, as confirmed by the measurements of the mean corpuscular volume, the histogram distribution of the red blood cells and the hematocrit. In all cases the Kleihauer test and isoelectrofocusing of the hemoglobins were performed. Coagulation factors were also studied in 60 cases. In 17 cases a medical abortion was voluntarily induced after the procedure, and the follow-up was normal during the observation period after sampling. In the other cases, pregnancies have continued normally and twelve healthy babies have already been born.