First trimester aneuploidy screening using nuchal translucency, free beta human chorionic gonadotrophin and maternal age.

Screening for aneuploidy using maternal age has a low detection rate and high false positive rate. Second trimester maternal serum screening increases trisomy 21 detection and decreases the false positive rate. First trimester screening would enable definitive diagnosis with chorionic villus sampling, and simple surgical termination of affected pregnancies would still be an option. Nuchal translucency (NT), free beta human chorionic gonadotrophin (f beta HCG) and maternal age were assessed in 302 patients before chorionic villus sampling. NT positively and f beta HCG negatively correlated with gestation, but neither correlated with maternal age nor with each other. Both NT and f beta HCG were increased in trisomy 21. NT was increased and f beta HCG was decreased in trisomy 18. Multivariate discriminant analysis enabled 87.5% detection of trisomy 21 in this high-risk population, for a 14% false positive rate. In a simulated normal population, using a risk cut-off of 1 in 250, 71% detection was achieved for a 7% false positive rate. The combination of NT, f beta HCG and maternal age is a simple, readily available and viable first trimester screening strategy.

Disappearing lung echogenicity in fetal bronchopulmonary malformations: a reassuring sign?

Congenital bronchopulmonary malformations detectable on prenatal ultrasound include cystic adenomatoid malformation (CAM), lobar sequestration, and upper airway atresia. We describe three fetuses with prenatally detected intrathoracic lesions in which the associated pulmonary hyperechogenicity disappeared before delivery. In the first case of pulmonary sequestration, the infant was asymptomatic after birth. However, in a case of CAM and another with laryngeal atresia, respiratory distress developed after delivery, despite recent scans showing apparently normal lung fields. This experience suggests that ultrasonic resolution of hyperechogenic lung lesions in utero does not necessarily indicate resolution of the underlying pathology.

Fetal ovarian cysts: diagnostic and therapeutic role for intrauterine aspiration.

Antenatal diagnoses of fetal ovarian cysts have not usually been confirmed until postnatal surgery. We describe 2 cases of hemorrhage into fetal ovarian cysts in which cyst aspiration in utero allowed both confirmation of the diagnosis prenatally and obviated the need for neonatal surgery. In both cases, cytology of the cyst aspirate demonstrated luteinized granulosa cells and biochemistry showed estradiol levels of > 10,000 pmol/l, indicating ovarian etiology. Hemorrhage, which had been suspected on ultrasound, was confirmed by cytology, showing hemosiderin-laden macrophages. There was no evidence of recurrence in either case following aspiration. The described association of fetal hypothyroidism was excluded by testing thyroid function in cord blood and/or cyst aspirate. We suggest that intrauterine aspiration contributes to the management of fetal ovarian cysts by confirming their ovarian origin, demonstrating the presence or absence of hemorrhage and facilitating preservation of ovarian function both by reducing the risk of torsion and the need for neonatal surgery.

Outcome of 1500 consecutive chorionic villus samplings.

OBJECTIVE: To evaluate the clinical complications and diagnostic problems of chorionic villus sampling. DESIGN: A pragmatic retrospective analysis. SETTING: Tertiary obstetric referrals mostly to private practice; sampling carried out at Royal Prince Alfred Hospital; diagnostic analysis usually at Oliver Latham Laboratory, or the Clinical Immunology Research Centre, Royal Prince Alfred Hospital, New South Wales. PATIENTS: 1500 women in the first trimester of pregnancy requesting prenatal diagnosis because of a risk of chromosomal or inherited genetic disorder in the fetus. INTERVENTIONS: Ultrasound-guided passage of a catheter into the chorion through the cervix. MAIN OUTCOME MEASURES: Incidence of unintended abortion, preterm births, low weight infants and discrepant karyotypes. RESULTS: There were 42 unintended abortions (3.0%), about 0.4% higher than the background abortion rate in women of similar age. Abortion did not occur more frequently in women with vaginal bleeding earlier in that pregnancy. Rates of preterm births and birth of low birthweight infants did not differ from the general population. A second diagnostic test was required in 68 women (4.5%). Mosaicism and tetraploidy were usually confined to the chorion. CONCLUSION: Chorionic villus sampling is an acceptable diagnostic test. Amniocentesis should be offered to patients who show mosaicism or tetraploidy.

DNA analysis for antenatal diagnosis of thalassaemia and haemophilia.

Two years' experience with DNA analysis for the antenatal diagnosis of thalassaemia and haemophilia is described. The advantages of DNA testing, including a first-trimester diagnosis and greater availability, must be considered in relation to the problems that are associated with this procedure. In particular, the risk of recombination in DNA polymorphism studies should be understood and explained fully to the patient.

Abnormal karyotype in the chorion, not confirmed in a subsequently aborted fetus.

An abnormal fetal karyotype, containing a del 16(q21-qter) as an extra chromosome, was diagnosed in all 14 metaphases examined in a sample of chorionic villous biopsy material. After elective abortion a mosaicism for this cell-line together with a normal one was detected in the chorionic tissue. Fibroblast cultures from several fetal skin biopsies all revealed a normal karyotype.

Clinical experience with 50 cases of first-trimester fetal diagnosis by chorionic biopsy.

Prenatal diagnosis by chorionic biopsy was undertaken between the eighth and 12th weeks of pregnancy in 50 patients at risk of chromosomal or genetic abnormalities. Samples from 45 patients were karyotyped. A DNA analysis for the detection of homozygous beta-thalassaemia was undertaken in five patients. The sample from one patient at risk of haemophilia in the fetus was subjected to DNA analysis after a male fetus was confirmed on karyotyping. Abnormal karyotypes were detected in four fetuses while three had homozygous beta-thalassaemia.

Ultrasound guided chorion biopsy in antenatal diagnosis of genetic disorders.

The technique of transcervical chorion biopsy was evaluated in women about to undergo therapeutic termination of pregnancy. The trophoblast biopsy catheter (Portex) under real-time ultrasound guidance was the most reliable in obtaining chorionic villi. The overall success rate for chorion biopsy was 73% in the first 100 patients studied.