The role of physician preferences in the choice of amniocentesis or chorionic villus sampling for prenatal genetic testing.

Our objective was to determine the effect of physician preferences, as well as physician demographic, obstetric, and practice-related factors, on the choice of prenatal test made by their patients. We studied preferences for prenatal outcomes for 372 pregnant women who either chose amniocentesis (AMN) (n = 288) or chorionic villus sampling (CVS) (n = 84) for the indication of maternal age. We also studied preferences for these outcomes for the 92 physicians that referred them for testing. Preferences were assessed using written scenarios and were measured on linear rating scales. According to patients, the choice of prenatal test was made entirely or mostly by the physician in 14% of cases and was shared equally between patient and physician in 37% of cases. After adjustment for patient preferences, physician concern about spontaneous abortion of a normal fetus after CVS (odds ratio 0.71; CI, 0.48-1.05; p = 0.08), and a limb reduction (LRD) birth after CVS (odds ratio 0.85; CI, 0.68-1.05; p = 0.12), tended to decrease their patients' odds of choosing CVS, but the results were not statistically significant. No other physician preference, and no physician demographic, obstetric, or practice-related factor, influenced patient test choice. We conclude that after taking patient preferences into account, physician preferences and practice-related factors did not emerge as significant determinants of the choice of prenatal test made by their patients. It remains possible, however, that physician concern about spontaneous abortion and about LRD increase the likelihood of their patients choosing AMN over CVS.