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

Transfusion and the use of blood products

I have reviewed areas of development in the use of blood and blood products, placing emphasis on the complications of transfusion, particularly transmission of infection. Alloimmunization in relation to transfusion of red cells and platelets has been covered and suggestions for reducing this problem assessed. The potential methods of avoiding the infective complications have been discussed including the screening of blood for infective agents, the virucidal treatment of blood products during the manufacturing process and white cell depletion. The use of recombinant DNA technology to produce coagulation factors offers the possibility of further reducing infective risks. An area of clinical promise is the use of haematopoietic growth factors to treat bone marrow failure, either congenital or acquired, such as the myelosuppressive effects of cancer chemotherapy, and reduce reliance on blood products. The aim of the chapter is to encourage the rational use of a limited resource by considering the risks inherent in transfusion and alternative strategies. In doing this it is important to audit current and future practice, and it is suggested that reference is made to the suggestions of Hume (1989) for quality assessment and assurance in paediatric transfusion medicine.

Comparative study of the fibrinolytic system in human fetuses and in pregnant women

Levels of major parameters of fibrinolysis were measured in 50 normal human fetuses between 19 and 39 weeks of gestation and compared to those of 50 healthy normal pregnant women and 30 adult controls. In fetuses, euglobulin clot lysis time (ECLT) was significantly shortened, plasminogen level was low and histidine-rich glycoprotein undetectable. While t-PA and u-PA levels were slightly lower than in adult controls, a significant decrease in PAI activity was demonstrated and no PAI-2 could be detected in fetal plasma. In contrast with these findings, the fibrinolytic equilibrium of pregnant women exhibited a prolonged ECLT and a strong increase in both PAI activity and PAI-2 antigen levels, while only a moderate elevation in u-PA and t-PA levels was measured.

Management of immune haemolytic disease in the fetus

Although Rh alloimmunization has been successfully reduced in frequency and severity since the implementation of Rh immune globulin, cases still occur. The management of affected pregnancies requires the efforts of a team which includes obstetrics/fetal medicine, the blood transfusion service, haematological support, nursing assistance and neonatology. The aim of antenatal management is to predict whether or not the fetus is severely affected, to correct the fetal anaemia and to deliver the baby at the optimal time. The management has improved markedly with the introduction of high-resolution real-time ultrasound, fetal blood sampling, intravascular fetal blood transfusion and/or intraperitoneal transfusion and meticulous fetal surveillance. With appropriate and timely management in severely alloimmunized patient, the survival rate of affected fetuses in some centres is now about 90%. There is still a need for research into new methods of treatment such as high dose intravenous immunoglobulin, which might non-invasively diminish fetal red cell destruction. Due to the reduced frequency of severe disease, regionalized treatment centres are essential in order to maximize the experience and efficiency of the management teams.

Flecainide in the treatment of fetal tachycardias

Fourteen mothers were treated with flecainide for fetal atrial tachycardias associated with intrauterine cardiac failure. Twelve of the 14 fetuses responded by conversion to sinus rhythm. One of the 12 fetuses subsequently died in utero. The remaining fetuses suffered no morbidity and were alive and well 3 months to 2 years after delivery. The two fetuses in whom atrial tachycardia did not convert with flecainide were successfully treated with digoxin. These results compare favourably with previous forms of antiarrhythmic treatment. After recent reports of the side effects of flecainide treatment, however, it has been advised that this drug should be confined to high risk patients and those with life threatening arrhythmias. The use of flecainide for fetal arrhythmias should be limited to patients with severe fetal hydrops and supraventricular tachycardias. It should not be the first drug of choice in atrial flutter.

Assessment of fetal well-being with magnetic resonance

The application of magnetic resonance techniques in the assessment of fetal growth, fetal growth patterns and fetal health was assessed. Eighty-four sets of fetal images were obtained using a fast-scan magnetic resonance imaging technique. Measurements were made of fetal subcutaneous fat thickness, uterine cavity length and width, fetal and uterine cross-sectional areas and fetal volume. Fetal area and fetal volume measurements were found to correlate well with birth weight. Measurement of subcutaneous fat thickness may prove to be a means of differentiating between those fetuses who are constitutionally as opposed to pathologically large or small. Thirteen women had additional spectroscopic studies carried out. Twelve of the women had normal pregnancies. One woman had a twin pregnancy in which one twin died. 31P phosphorus spectra were obtained from seven of the normal pregnancies. In the remainder, the depth of the abdominal wall prevented spectra being obtained from the placenta. Differences in phosphorus metabolites were obtained from the placenta of the dead twin compared to those from the healthy pregnancies.

Ultrasonographic method for detection of haemoglobin Bart's hydrops fetalis in the second trimester of pregnancy

In nine pregnant women at risk for fetal alpha-thalassaemia, the two affected fetuses were diagnosed by ultrasonography at 18-20 weeks' gestation. In countries with limited resources, ultrasonography provides a cost-effective method of prenatal screening for this condition.

Fetal platelet counts in thrombocytopenic pregnancy

Fetal platelet counts were assessed by percutaneous umbilical blood sampling in 64 pregnancies (62 women) with maternal thrombocytopenia. In 33 pregnancies associated with chronic immune thrombocytopenia, 11 of the fetuses had platelet counts below 150 x 10(9)/l and 4 were severely thrombocytopenic (less than 50 x 10(9)/l). In 31 pregnancies with symptomless maternal thrombocytopenia as an incidental finding, 4 fetuses were thrombocytopenic, 1 of them severely. Maternal indices, including antiplatelet antibodies, did not correlate with risk of fetal thrombocytopenia; and in those with repeat measurements there was no evidence of benefit from treatment with either corticosteroids (4 cases) or intravenous immunoglobulin (3 cases). Percutaneous umbilical blood sampling, a safe procedure in experienced hands, provides accurate platelet counts in thrombocytopenic pregnancy, as an aid to decisions on mode of delivery and to assessment of treatments.

Detection of rubella virus in amniotic fluid by electron microscopy

We report in this paper the observation of rubella virus by electron microscopy in an amniotic fluid sample, collected from a pregnant woman with rubella infection. Virological investigations by inoculation of cell cultures with amniotic fluid and fetal blood remained negative, due probably to the presence of neutralizing antibodies in the samples. Electron microscopy is a rapid but weakly sensitive method to detect viruses in clinical specimens. However, this unusual observation would indicate that in some cases electron microscopy could be a useful technique to evidence a fetal rubella infection.

Limited role of fetal blood sampling in prediction of outcome in intrauterine growth retardation

Fetal acid-base status was evaluated on 66 blood samples taken for rapid karyotyping from 58 growth-retarded fetuses. Before blood sampling, doppler blood flow studies of the umbilical artery showed end-diastolic frequencies to be absent in 32 fetuses (group 1) and present in 26 (group 2). Fetuses with chromosomal (n = 4) or structural (n = 8) abnormalities were excluded from subsequent analysis. Gestational age at blood sampling (27.8 [95% CI 26.5-29.1] vs 32.2 [30.4-34.1] weeks) and time from sampling to delivery (median 2 (range 0-35] vs 14 [0-77] days) were significantly lower in group 1 than group 2. There were no perinatal deaths in group 2 whereas mortality in group 1 was 65.4%. There were significant differences between the groups at blood sampling in pH, pO2, pCO2, base equivalents, and nucleated-red-cell count, but within group 1 these measurements were similar in surviving fetuses and those who died perinatally. Since acid-base determination does not predict perinatal outcome in growth-retarded fetuses, fetal blood sampling has a limited role in monitoring fetal wellbeing.

Second-trimester placental biopsy for rapid fetal karyotyping

Since January 1988 the technique of first-trimester chorionic villus sampling (placental biopsy) has been extended to include cases in the second trimester. To date, 40 procedures have been performed. The main indication for the late chorionic villus sampling was a low serum alpha-fetoprotein value in association with an increased risk for Down syndrome (n = 28), abnormal ultrasonographic finding (n = 7), and failed amniotic cell culture (n = 3). Successful karyotype results were achieved in all but two cases. Most results were obtained within 48 hours with direct cytogenetic techniques. No cases of mosaicism were found. The highest yield of abnormal karyotypes was obtained from the cases with abnormal ultrasonographic findings (one trisomy 21, two 45,X). One case of trisomy 21 was identified in the 28 cases of low serum alpha-fetoprotein. No spontaneous losses have occurred. The technique is easy to learn, does not differ from first-trimester procedures, and may have a lower complication rate than cordocentesis. The reporting of cases to the CVS Newsletter should help evaluate late chorionic villus sampling as another method for rapid fetal karyotyping.

Effects of intravascular, intrauterine transfusion on prenatal and postnatal hemolysis and erythropoiesis in severe fetal isoimmunization

In an investigation of the effects of intrauterine, intravascular transfusions (IUT) on fetal and neonatal hemolysis and erythropoiesis, 12 fetuses who received IUT for treatment of severe isoimmunization had serial measurements of hemoglobin concentration, Kleihauer-Betke stains to detect fetal hemoglobin-containing erythrocytes, and determination of plasma erythropoietin (EPO) concentration before each IUT, at birth, and postnatally. Reticulocyte counts and sensitizing antibody titers were measured in five fetuses. Mean values before the first IUT, before the final IUT, and at birth were as follows: hemoglobin level, 6.1, 9.1, and 11.3 gm/dl; reticulocyte count, 22.7%, 0.5%, and 0.9%; fetal hemoglobin-containing erythrocytes, 100%, 1.6%, and 1.5%; and EPO level, 12, 56, and 756 mU/ml, respectively. Only one neonate required exchange transfusion. In the first month postnatally, all infants had a profound anemia. All but one infant required simple blood transfusions postnatally. Before the first postnatal transfusion, mean hemoglobin concentration was 6.2 gm/dl, mean reticulocyte count was 0.8%, mean erythropoietin concentration was 23 mU/ml, and the sensitizing antibody titer remained markedly elevated. Except for the surge of EPO at birth, EPO levels did not rise prenatally or postnatally unless marked anemia (hemoglobin level less than 5 gm/dl) occurred. These observations suggest that the intrauterine and postnatal anemia in fetuses who receive IUTs may be explained both by hemolysis of newly formed erythrocytes by circulating antibody, which typically persisted for more than a month after birth, and by suppressed erythropoiesis.

What is known about the prevention of congenital toxoplasmosis?

The French programme for the prevention of congenital toxoplasmosis consists of the diagnosis and treatment with spiramycin of acute infections during pregnancy and monthly follow-up of all identified seronegative women. The major flaw is that the efficacy of spiramycin in preventing contamination of the fetus, or at least in reducing the extent of the infection, has never been evaluated in a randomised placebo-controlled clinical trial. Its evaluation would require the follow-up of children born to mothers contaminated during pregnancy for more than 6 months, a goal that is difficult to obtain in current practice. The cost of the programme depends largely on the proportion of non-immune women of childbearing age. Since the modes of contamination are known and are linked to living habits, it should be possible to reduce the risk of infection during pregnancy by adequate health education. This approach is still to be evaluated.

Prenatal diagnosis of congenital cytomegalovirus infection: two decades later

Cytomegalovirus is the most common cause of congenital infection in the United States, yet there has been little progress in the prenatal diagnosis of this intrauterine infection. We present evidence that viral culture of amniotic fluid may be a useful adjunct procedure, when performed as part of the antenatal evaluation of suspected fetal cytomegalovirus infection.

Estimation of the risk of thrombocytopenia in the offspring of pregnant women with presumed immune thrombocytopenic purpura

BACKGROUND AND METHODS

The optimal management of immune thrombocytopenic purpura during pregnancy remains controversial because the risk of severe neonatal thrombocytopenia remains uncertain. We studied the outcome of the index pregnancy in 162 women with a presumptive diagnosis of immune thrombocytopenic purpura to determine the frequency of neonatal thrombocytopenia and to determine whether neonatal risk could be predicted antenatally by history or platelet-antibody testing.

RESULTS

Two maternal characteristics were identified as predicting a low risk of severe neonatal thrombocytopenia: the absence of a history of immune thrombocytopenic purpura before pregnancy, and the absence of circulating platelet antibodies in the women who did have a history of the condition. Eighteen of 88 neonates (20 percent; 95 percent confidence interval, 13 to 30 percent) born to women with a history of immune thrombocytopenic purpura had severe thrombocytopenia (platelet count less than 50 x 10(9) per liter at birth), as compared with 0 of 74 (0 percent; 95 percent confidence interval, 0 to 5 percent) born to women first noted to have thrombocytopenia during pregnancy (P less than 0.0001). Among the women with a history of immune thrombocytopenic purpura, 18 of 70 neonates (26 percent; 95 percent confidence interval, 16 to 38 percent) born to those with circulating platelet antibodies had severe thrombocytopenia, as compared with 0 of 18 infants (0 percent; 95 percent confidence interval, 0 to 18.5 percent) born to those without circulating antibodies (P less than 0.02). Thus, the risk of severe neonatal thrombocytopenia in the offspring of women without a history of immune thrombocytopenic purpura before pregnancy and of women with a history of the condition in whom circulating platelet antibodies are not detected was 0 percent (95 percent confidence intervals, 0 to 5 and 0 to 18.5 percent, respectively).

CONCLUSIONS

The absence of a history of immune thrombocytopenic purpura or the presence of negative results on circulating-antibody testing in pregnant women indicates a minimal risk of severe neonatal thrombocytopenia in their offspring.

Holoprosencephaly: prenatal diagnosis by sonography and magnetic resonance imaging

Magnetic resonance (MR) imaging was performed on two women at the 33rd and 34th pregnancy week, respectively, after ultrasonographic detection of a brain malformation. Fetal neuromuscular blockade was induced by pancuronium bromide injected into the umbilical vein under continuous ultrasound (US) guidance. MR images supported the echotomographic diagnosis of holoprosencephaly, improving the image quality and offering additional information in such cases of difficult differential fetal diagnosis. Holoprosencephaly was finally confirmed by neonatal US and autopsy (case 1), US, CT and MR (case 2).

Cordocentesis for rapid karyotyping

Pure fetal blood was obtained by cordocentesis in 101 fetuses of 96 patients at 15 to 38 weeks' gestation. Rapid karyotype was obtained within 2 to 4 days by fetal lymphocyte culture. Chromosomal abnormality was detected in 12 (11.9%) fetuses. Abnormal karyotype was found in 5 of 44 fetuses with structural malformations, 3 of 13 fetuses with intrauterine growth retardation or oligohydramnios, 1 of 3 fetuses with nonimmune hydrops fetalis, 2 (one monozygotic set) of 10 discordant twins, 1 of 12 isoimmunized gestations, none of 8 cases with advanced gestational-maternal age, and none of 6 immune thrombocytopenia cases. This suggests that rapid karyotype should be obtained in all cases of fetal structural malformations, intrauterine growth retardation, and nonimmune fetal hydrops, and may be obtained incidentally in isoimmunized pregnancies and discordant twins to assist in clinical management.

Abruptio placentae after percutaneous umbilical cord sampling: a case report

The use of umbilical cord sampling is becoming more widespread. The full risk of the procedure, however, is not completely known. Reported here is a case of abruptio placentae immediately after percutaneous umbilical cord sampling.

Benefits of placental biopsies for rapid karyotyping in the second and third trimesters (late chorionic villus sampling) in high-risk pregnancies

In a total of 301 placental biopsies in the second and third trimesters, 225 were performed because of suspicious ultrasonographic findings. In this group there was a high rate of aneuploidies (20%). As opposed to the alternative methods for rapid karyotyping, placental biopsies can easily be performed even in pregnancies with abnormal amounts of amniotic fluid. Oligohydramnios and polyhydramnios were key ultrasonographic findings in 38% of cases and were found to be associated with 22% of abnormal chromosomal findings. Suggestive ultrasonographic findings seem to justify the exclusive use of direct preparation.

The ferning test for detection of amniotic fluid contamination in umbilical blood samples

There is currently no standard means of detecting amniotic fluid contamination in fetal blood obtained by percutaneous umbilical blood sampling. The ferning test is proposed for this purpose. An in vitro model, using centrifuged serial dilutions of neonatal cord blood and amniotic fluid, showed that ferning of the supernatant occurs in proportion to the degree of contamination. A system for grading ferning was devised, and tested in a blind trial. For the detection of amniotic fluid contamination of 10% or more, the method showed a sensitivity of 98% and a specificity of 81%. The method may be useful in percutaneous umbilical blood sampling, and in the diagnosis of spontaneous rupture of membranes with vaginal bleeding.

New approaches in the treatment of haemolytic disease of the fetus

The incidence of Rh haemolytic disease of the fetus and newborn complicating pregnancy has fallen since the implementation of prophylaxis with Rh immune globulin. However, occasional mismatched blood transfusions and ineffective or inadequate prophylaxis still result in a few Rh-alloimmunized patients requiring treatment during pregnancy. The development of a safe technique for obtaining pure fetal blood samples has provided the opportunity to assess correctly the severity of anaemia and to study fetal haematology and biochemical parameters, and hence to gain a better understanding of the pathophysiology of this condition. The aim of antenatal management is to predict whether or not the fetus is severely affected, to correct fetal anaemia and to deliver the baby at the optimal time. Fetal IVT is the standard treatment in severe Rh alloimmunization in many centres. However, high volume transfusion without overloading the fetal circulation, as well as increasing the interval between transfusions without jeopardizing the fetal condition, can be achieved by a combination of IVT and IPT. Thus, the total number of transfusions needed and the overall procedure-related risk for each fetus is reduced. With the recent advances in fetal medicine, haematology and neonatology, the survival rate of affected fetuses in some centres is now about 90%. Fetal death will continue to be associated with two sets of circumstances: trauma or complications due to IVT or IPT in early gestation when delivery is not feasible, and late referrals with such severe hydrops that its reversal is not possible. There is still, therefore, a need for research into new methods of treatment, such as high dose intravenous IgG, which can non-invasively diminish fetal red cell destruction.

Pure fetal blood samples obtained by cordocentesis: technical aspects of 322 cases

Three hundred and twenty-two percutaneous umbilical blood samplings were performed over 4 years in our prenatal diagnostic centre. A 3.5 MHz sector ultrasound transducer was used to guide a 22.5-gauge needle under local anaesthesia. Sampling was performed for rapid fetal karyotyping (within 72 h) in 120 cases, for diagnosis of fetal toxoplasmosis in 133 cases, for determination of the severity of Rh immunization in 15 cases, and for diagnosis of congenital rubella in 4 cases. Pure fetal blood was obtained in 98.7 per cent of the cases after two attempts. The approach to the cord was either transamniotic or transplacental. Puncturing was preferentially done at the placental insertion of the cord (72.2 per cent of the cases) and the mean blood sample volume was 3.5 ml. The rate of fetal death in utero was 1.9 per cent, including two cases of amnionitis, one trisomy 18, and one severe bradycardia. The failures were due to sampling at an early stage of pregnancy (before gestation week 18), to maternal obesity, oligohydramnios, and the inexperience of the operator.

Pathology of intragestational intervention in twin-to-twin transfusion syndrome

Selective intervention in multiple pregnancy is being used to enhance the chances of survival of at least one conceptus when the risks for the combined conceptuses and mother are considered too great. These procedures have been applied to induced polyembryonic conceptions (selective continuance) and discordant dichorionic twins (selective birth). We report attempts at selective intervention in three monochorionic twin gestations affected by twin-to-twin transfusion syndrome. In all three cases, both fetuses seemed doomed and the mother was in significant distress. The selected survivor in the first case is doing well; both twins were stillborn in the second case; in the third case, the selected survivor died as a neonate but the other twin survived and is doing well. We suggest possible explanations for the clinical outcome of each case based on detailed pathologic examination of the delivered placentas and autopsy examination of the nonsurviving twins. The shared chorionic circulation is the source of both the clinical disorder and the potential complications of any attempt to alleviate the disorder. This situation is unique to monochorionic twins, and we discuss the implications of this for intrauterine therapy of twin-to-twin transfusion syndrome.

Umbilical amino acid concentrations in normal and growth-retarded fetuses sampled in utero by cordocentesis

Fetal plasma amino acid concentrations were obtained by cordocentesis at midgestation in 11 normal (appropriate for gestational age) fetuses and at late gestation in 12 small-for-gestational-age fetuses, and at cesarean section in 14 normal term infants. In normal fetuses total molar amino acid concentrations and fetal/maternal total molar concentration ratios did not change significantly between the second and third trimesters. Fetal and maternal concentrations of most amino acids were significantly correlated at both midgestation and late gestation. Small-for-gestational-age fetuses had significantly lower concentrations of total alpha-aminonitrogen; this was mainly because of a reduction of the branched chain amino acids valine, leucine, and isoleucine, and of lysine and serine. Maternal arterial concentrations of phenylalanine, arginine, histidine, and alanine were elevated in small-for-gestational-age pregnancies. Thus there are only minor changes in amino acid concentrations between midgestation and late gestation in normal fetuses with a constant fetal/maternal ratio. In small-for-gestational-age infants a significant reduction in alpha-aminonitrogen and in most essential amino acids was demonstrable in utero weeks before delivery.

Counseling and decision dilemmas associated with fetal blood sampling

Counseling before fetal blood sampling via cordocentesis is more difficult than that done before amniocentesis because 1) a fetal anomaly has been detected or is very likely, 2) the cordocentesis procedure may have a higher risk than does amniocentesis, and 3) the gestational age is frequently advanced before referral. These factors result in counseling and decision dilemmas that include that 1) the advanced gestational age may preclude the option of termination, 2) fetal prognosis may be poor despite normal cytogenetic results, and 3) the benefit of a diagnosis to provide indications for various delivery options must be weighed against the psychological burden of documenting a chromosome abnormality far in advance of delivery. Thus, counseling before cordocentesis requires engaging the couple in decision making regarding potential management of the pregnancy as a prerequisite to choosing or declining the procedure.

Umbilical cord haematoma as a complication of intrauterine intravascular blood transfusion

Between October 1985 and February 1989, 49 ultrasound-guided intravascular fetal blood transfusions were performed in 16 patients (14 with rhesus (Rh) isoimmunization, 2 with non-immunologic hydrops fetalis (NIHF)). As an intra-operative complication, perivascular haematoma of the cord occurred in three patients (7 per cent). In two cases, fetal bradycardia necessitated delivery by Caesarean section at 30 and 32 weeks' gestation, respectively. In the third case, fetal bradycardia developed during transfusion, at 31 weeks' gestation, but normalized within 3 min. The baby was delivered as planned at 36 weeks of gestation, after another transfusion at 34 weeks. Dislodgement of the needle tip into perivascular tissue, caused by sudden fetal or maternal movements, is the reason for this complication. The haematoma develops as a result of delayed recognition and continuous transfusion into Wharton's jelly. Cord haematoma may be diagnosed in time by continuous ultrasound imaging, as illustrated in case 3. To minimize the risk of needle dislodgement during transfusion, sedation of the mother and complete immobilization of the fetus by injecting a short-acting muscle relaxant into the umbilical vessel are recommended.

Fetal heart rate responses to anemia in Rh isoimmunization

On 52 occasions 24 Rh immunized women were monitored with a nonstress test (NST) prior to fetal blood sampling. Cardiotocographic characteristics were recorded for each NST. Fetal blood was analysed for hemoglobin and hematocrit. Fetal hemoglobin and hematocrit were positively correlated to long-term variability, acceleration amplitude and negatively correlated to deceleration amplitude (linear regression analysis; p less than 0.05). Decelerations were almost without exception associated with low concentrations of hemoglobin and hematocrit. In fetuses of 32 weeks' gestation or more, a loss of variability (less than or equal to 5 bpm) was associated with severe anemia. Hemoglobin and hematocrit were significantly lower in the group with a pathological NST (n = 15) compared with the group with a normal NST (n = 37) (Mann-Whitney U test; p less than 0.05). The predictive value of a pathological test was 13/15 concerning hemoglobin and hematocrit; whereas, the predictive value of a normal test was poor. A pathological NST, especially when decelerative, is a good predictor of fetal anemia, but a normal NST is no guarantee for a normal blood status.

Prenatal diagnosis of thrombocytopenia absent radius syndrome by ultrasound and cordocentesis

The prenatal diagnosis of thrombocytopenia absent radius (TAR) syndrome, utilizing ultrasound and cordocentesis, is described. To our knowledge, this represents the first prenatal diagnosis of this condition in an index case. The diagnostic evaluation of a fetus with upper extremity limb reduction defects is discussed.

Is there an association between fetal viral infection and fetal malformation? I. Detection of specific IgM antibodies in the serum of malformed fetuses

Determinations of IgG and IgM antibodies specific for cytomegalovirus (CMV), herpes simplex virus (HSV1), herpes simplex virus (HSV2), varicella-zoster virus (VZV), rubella, echo, Coxsackie and morbilli viruses were performed in 20 sera from malformed fetuses. Demonstration of a fetal infection by increased fetal serum IgM permits linkage to a detected fetal malformation. In parallel, 14 maternal sera and 17 amniotic fluid samples were examined. Laser nephelometry (a quantitative method) was used for the determination of IgM and IgG class immunoglobulins. None of the fetal sera were found to contain IgM class antibodies specific for the viral antigens studies. While IgM CMV-specific antibodies were present in one maternal serum, the specific IgM was absent in the fetus. The absence of specific IgM antibodies appears to warrant the conclusion that the malformed fetuses were uninfected by any of the above viruses. IgM antibodies were detected in two fetal sera by quantitative methods. The IgM antibodies present in two fetuses probably were generated in response to some other introduced antigen.

Fetal toxoplasmosis: outcome of pregnancy and infant follow-up after in utero treatment

Eight-nine cases of fetal Toxoplasma infection are reported in women treated with spiramycin during pregnancy. Thirty-four pregnancy terminations were performed (2.7% of the total number of acquired Toxoplasma infections during pregnancy). Fifty-two pregnancies were allowed to proceed (43 being additionally treated with pyrimethamine and sulfonamides), leading to the birth of 54 live infants. After a mean follow-up period of 19 months, 41 infants had evidence of subclinical Toxoplasma infection, 12 had a benign form, and one had severe congenital toxoplasmosis (this infant did not receive the additional treatment during pregnancy). Efficacy of the additional treatment with pyrimethamine and sulfonamides was demonstrated by a significant reduction of severe congenital toxoplasmosis and the relative decrease of the ratio of benign to subclinical forms. We recommended that spiramycin treatment be started as soon as possible once the diagnosis of maternal Toxoplasma infection during pregnancy is proved or strongly suspected, because a prolonged time interval between onset of infection and start of treatment seems to be associated with the presence of severe fetal lesions at the time of prenatal diagnosis.

Maturation of thyroid function in normal human foetuses

The functional maturation of an independent foetal thyroid activity was investigated in the present study. Serum concentrations of total T4, free T4, TSH and TBG were measured in 23 foetuses between 18 and 31 weeks' gestational age. Foetal samples were collected by transabdominal needling from the placental cord insertion. TT4, FT4, TBG and TSH levels significantly increased with gestational age. FT4 levels were comparable with the adult range by 28 weeks' gestation; TBG levels reached adult values at approximately 30 weeks, while TT4 was lower than adult levels throughout the whole period studied. TSH values were, in all cases, higher than the normal adult range. A significant positive correlation was present between TT4 and TBG, TT4 and TSH, and TBG and TSH levels; on the contrary, no correlation was demonstrated between FT4 and TSH levels. The TSH/TT4 ratio significantly decreased with gestational age. The results suggest an incomplete responsiveness of the foetal thyroid gland to TSH, while the feedback control system between pituitary and thyroid is operating at a different set point from that in post-natal life. The normal range of thyroid parameters established is of clinical relevance for the antenatal diagnosis, and eventual treatment of thyroid disorders that may seriously damage foetal development and maturation.

Hydrops revisited: literature review of 1,414 cases published in the 1980s

This paper reviews 47 series of hydrops fetalis (804 cases) and 610 individual cases published since 1980. From this large number of cases, guidelines are derived for prenatal diagnosis and management.

Maternal-fetal glucose gradient in normal pregnancies and in pregnancies complicated by alloimmunization and fetal growth retardation

Maternal and fetal glucose concentrations were measured simultaneously in 54 pregnancies in which fetal blood sampling was conducted between 18 and 34 weeks gestation. Twenty-five pregnancies were normal (group 1), 13 were complicated by fetomaternal alloimmunization (group 2), and 16 by intrauterine growth retardation (group 3). The maternal glucose concentration was similar in the three groups. The fetal glucose level was significantly lower in growth-retarded (mean = 2.7 mmol/L) than in normal pregnancies (mean = 3.5 mmol/L). There was a statistically significant gradient between maternal and fetal glucose concentrations in groups 1 and 3, but no gradient was found in group 2. Maternal and fetal glucose concentrations were significantly correlated in all groups, but the correlations were distinct. For a given maternal glucose concentration, fetal glucose was higher in patients with alloimmunization and lower in patients with intrauterine growth retardation than in normal pregnancies. In patients with intrauterine growth retardation, fetal PO2 correlated positively with fetal glucose and inversely with maternal fetal glucose gradient.

Corticosteroid sulfates in fetus plasma

The sulfates of deoxycorticosterone (DOCS), corticosterone (BS), cortisone (ES) and cortisol (FS) were radioimmunoassayed in umbilical vein blood plasma samples collected in 97 fetuses between 19 and 32 weeks of gestation after extraction and chromatography on Sephadex LH 20 columns. While DOCS and BS displayed a decreasing pattern until 27-28 weeks, FS and ES did not show important variations throughout the period considered. All sulfates, excepted BS, increased at 29-30 weeks but this rise was only significant for FS and ES. Thereafter BS significantly increased while no significant difference could be displayed for the three others. In view of the difference between the patterns of 17-deoxy- and 17-hydroxycorticosteroids, one can speculate that, during this period of pregnancy, a shift in steroid biogenesis might occur towards a more important production of cortisol. DOCS was correlated with BS and with FS but not with ES. FS was correlated with the three other sulfates and with unconjugated F. ES was correlated with BS and FS but not with DOCS or unconjugated E. The significance of these correlations are discussed according to the origin and the metabolic interrelationships of the four steroid sulfates and unconjugated F and E.

Screening with Doppler velocimetry in labor

Doppler flow velocimetry was performed on 273 nonselected patients in labor. All patients were at least 2 cm dilated and 80% effaced (58% greater than 4 cm) and were delivered of infants within 24 hours. Fetal heart rate tracing performed at the same time was read by another observer and compared with Doppler flow velocity measurements (systolic/diastolic ratio, pulsatility index). A significant correlation was noted (r = 0.234, p less than 0.001) between the two modalities. Both fetal heart rate tracings and umbilical flow velocity measurements were correlated with fetal outcome. Significant associations were noted between the umbilical systolic/diastolic ratio and fetal distress. 5-minute Apgar scores, the need for intubation independent of gestational age, and umbilical arterial cord pH and base excess. It appears that the information obtained from flow velocimetry had additional benefits compared with that of fetal heart rate tracings alone.

Schizencephaly: prenatal diagnosis by computed sonography and magnetic resonance imaging

Magnetic resonance (MR) imaging was performed at 29 weeks of pregnancy after ultrasonographic detection of an abnormal cleft in the fetal brain. Fetal neuromuscular blockade was induced by pancuronium bromide injected into the umbilical vein under continuous ultrasound (US) guidance. MR images supported the echotomographic diagnosis of schizencephaly improving the visualization of symmetrical broad clefts connecting the lateral ventricles with the subarachnoid space. Schizencephaly was finally confirmed by neonatal US, computed tomography, and MR.