Chorionic villus sampling utilization following reports of a possible association with fetal limb defects.

Prenatal diagnosis choices were reviewed in 473 women who presented for genetic counselling prior to 11 weeks' gestation for the indication of advanced maternal age. Group A consisted of 336 patients who were unaware of a possible association between chorionic villus sampling (CVS) and limb defects. Group B consisted of 137 patients who were provided this information. Fifty-one per cent of patients in group A and 45 per cent of patients in group B chose CVS. This difference was not significant by chi 2 analysis (P = 0.7). Patterns of prenatal diagnosis procedure utilization from 1987 to 1992 revealed a significant reduction in CVS utilization accompanied by a corresponding increase in amniocentesis after the association between CVS and limb defects was publicized. Referrals for CVS counselling also significantly declined. However, acceptance rates did not change for those patients who received genetic counselling. First-trimester genetic counselling, including a discussion regarding a possible association between CVS and limb defects, helps patients make informed decisions concerning prenatal diagnosis options, and, in our population, resulted in no change in CVS acceptance rates.

Significance of mosaic isochromosome 20q on amniocentesis.

We report on 2 fetuses with prenatally diagnosed mosaic isochromosome 20q in amniotic fluid. Neither had an identifiable cytogenetic abnormality after birth. One infant developed a benign intracranial dermoid cyst at age 8 months. The other was completely normal in all respects. We are aware of 13 fetuses with this prenatally diagnosed chromosome finding; all fetuses tested have had normal chromosomes on subsequent cytogenetic studies and all, except one, have been morphologically normal. Fetuses with mosaic isochromosome 20q identified on amniocentesis are most likely to be phenotypically and cytogenetically normal after birth.

Knowledge of genetics among residents in obstetrics and gynecology.

A supervised genetics examination was administered to 76 obstetrics and gynecology (ob/gyn) residents from 15 different institutions in the Philadelphia area. The questions were specifically designed to be applicable to obstetrical practice. Overall, the mean score was 69% (range 32%-88%). Using the nonparametric Mann-Whitney rank sum test, we found that the 25 residents from institutions with an obstetrics-gynecology-genetics (OGG) program, coordinated by an obstetrician/gynecologist board certified in clinical genetics, had statistically significant higher scores than the remaining 51 residents from institutions without an OGG program (77% vs. 65%, respectively; P < .001). This study demonstrates that knowledge of genetics among residents in ob/gyn is deficient, especially among residents at institutions without OGG programs. Special efforts should be made to provide genetics education to these individuals. We propose that more obstetricians be encouraged to pursue postgraduate training in genetics in light of the rapid development of medical genetics; its application to prenatal screening, diagnosis, and counseling; the anticipated utilization of genetics services; and the need for educational initiatives geared toward ob/gyn patients.