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A case of arteriovenous fistula of the liver diagnosed at 30 weeks of gestation is reported. The etiologies of an hypoechogenic structure in the fetal liver are discussed showing the contribution of pulsed wave Doppler and color Doppler to the diagnosis. The clinical evolution towards heart failure led us to examine the pathophysiology of such a lesion. The prenatal management of this arteriovenous malformation is exposed.

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.

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.

Twin pregnancies pose particular problems in both prenatal diagnosis and obstetric management. We present 19 twin pregnancies that underwent fetal blood sampling (FBS). The indications were mostly similar to those for singleton pregnancies, with both fetuses being sampled. There was one indication specific to twin pregnancies; disseminated intravascular coagulation in the retained twin after the death-in-utero (DIU) of the other. In 5 cases, only 1 twin was sampled; in 2 because the second twin was female in the diagnosis of an X-linked disorder; in 1 because of technical failure, and in 2 the other twin had predeceased. Eight pregnancies continued after the FBS delivering 2 live, healthy infants, though 5 were delivered before 37 weeks of gestation. In 7 cases there was a discordance in the diagnosis between the twins. In 3 of these cases the affected fetus underwent selective termination by air embolism; in 2 cases the pregnancies were continued and the affected twin not resuscitated; 1 pregnancy is still in progress, and 1 patient had a non-medically supervised termination of both twins in another country. Two patients miscarried within a week of the FBS. Two patients had only 1 living twin at the time of FBS; 1 had a second DIU a month after the FBS and the other a neonatal death at 11 days of age in an infant with severe porencephaly. FBS is technically feasible for similar indications as for singleton pregnancies though discordance in diagnosis raises specific management problems.

The considerable development, during the last few years, of the antenatal diagnosis of congenital abnormalities is due to progress in cytogenetics but also to rapid improvements in obstetrical ultrasonography. With high-resolution ultrasound scanners, various interventions performed increasingly early during pregnancy can be guided with an ever decreasing risk. Thus, genetic diseases can now be detected at a very early stage by chorion biopsy combined with genetic engineering, and direct foetal blood sampling with a needle guided by ultrasound increases our knowledge of foetal physiology and provides an access to antenatal pathology. In the forthcoming years a true antenatal medicine will no doubt develop, no longer to eliminate foetuses, but to treat and cure them.

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.

The fetal karyotype was established during the second or third trimester of 18 at risk pregnancies after fetal blood sampling by direct puncture of the umbilical vein guided by real time ultrasound. Two karyotypes were abnormal. This rapid technique for karyotyping allows the obstetrician to decide early how the pregnancy should be conducted.