[Evaluation of the risks of transabdominal chorionic villus sampling. 600 cases]. / Evaluation des risques de la choriocentèse par voie transabdominale. A propos de 600 cas.

The authors report their experience with fine needle chorionic villus sampling carried out transabdominally. Six hundred antenatal karyotype diagnoses were made using this method. The indications were: maternal age: 509 (85%), previous chromosomal abnormalities: 57 (9.5%), parental chromosomal abnormalities: 19 (3%), X chromosome linked diseases: 9 (1.5%), others: 6 (1%). The patients were divided into two groups according as to whether the test was carried out before or after 12 weeks of amenorrhea (Group 1 and Group 2). Each group was divided into two sub-groups according to whether the amniotic membranes were broken or not. The test was carried out using a 20 gauge needle under ultrasound control with a to-and-fro movement using continuous aspiration. The success rate was 98.4%. Minor complications were rare. Contractions 9 (1.5%), spotting 4 (0.6%), small haematomas 13 (2.1%), loss of amniotic fluid 4 (0.6%). The level of unintentional abortions depended on the duration of the pregnancy and whether the amniotic cavity or not was entered. In group 1 (before or at 12 weak amenorrhea) there were 2 abortions out of 124 cases (1.6%) and if the needle entered the amniotic cavity 10 out of 57 cases (17.5%). In group 2 (after 12 weeks of amenorrhea) there was no ill effect from going into the amniotic cavity to the rest of the pregnancy. The abortion rates was 6 out of 419 (1.43%). There were no false positive or negative results.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosomal analysis of colonic adenomatous polyps.

Chromosomal analysis of 25 colonic adenomatous polyps was performed by a direct method similar to that used in prenatal diagnosis of chromosomal aberration on chorionic villi. Fourteen lesions showed an abnormal karyotype. Two changes were recurrent: trisomy 7 (observed in eight cases) and trisomy 13 (observed in seven cases). No monosomy of the short arm of chromosome 17 was observed even at the level of two polyps with in situ carcinoma lesions.

Risks of transabdominal chorionic villus sampling before the 12th week of amenorrhea.

The authors report on a series of 210 chorion villus sampling diagnoses made with a needle by the transabdominal route. The rate of fetal loss was 4.2 per cent. Placental localization was important: fetal losses were 8 per cent when the placenta was strictly posterior (transamniotic route), whereas it was only 1.6 per cent when it was not posterior. Moreover, all fetal losses occurred (apart from one at 12.5 weeks of amenorrhea) before the 12th week of amenorrhea. The authors suggest that choriocentesis by the transabdominal route should not be performed before the 12th week of amenorrhea, and that the amniotic membrane should not be disturbed before the 13th week of amenorrhea.

Direct chromosome analysis in the second and third trimesters by placental biopsy in 30 pregnancies.

Direct chromosome analysis was performed on placental villi obtained by ultrasound-guided transabdominal needle aspiration in 30 women at between 23 and 37 weeks gestation. Placental biopsy is simple in the presence of severe oligohydramnios where fetal blood sampling is usually more difficult. Direct karyotyping of placental villi is more rapid than chromosomal analysis from fetal blood and from amniotic fluid. Two chromosomal anomalies were discovered: one trisomy 18 and one 6p+. Villus sampling failed in one woman and two samples obtained at 36 and 37 weeks gestation could not be karyotyped. The procedure did not affect the outcome of the pregnancy.