PIP: Liberalization of abortion laws in several US states (e.g., New York and California) coincided with the development of prenatal techniques, which diagnose chromosomal abnormalities and biochemical disorders. Increased use of prenatal diagnostic services has not been accompanied by adequate examination of the decision making process women undergo when contemplating prenatal diagnosis, pregnancy termination, or experimental fetal therapy. The limited literature exploring these issues indicates that many women do not know as much as possible about the health of their fetus. Women who are at risk of abnormal pregnancy tend to become distressed and willing to accept invasive testing, even when they know the significant, albeit low, risks of such testing. Women's perceptions of risk, which stem from complex psychologic-phenomena, are likely to be very inconsistent with objective reality. Neither counseling nor education can easily change these misperceptions. Nevertheless, counseling can at least alter misperceptions enough so they move closer to objective reality. On the other hand, counseling can sway perceptions and choices made based on these perceptions. Decision making is even more complex and emotional when women encounter abnormalities. Considerable social, moral, and psychologic factors influence this process, making this a very problematic area to study. Almost all women who carry an abnormal fetus with a very serious prognosis and a high degree of diagnostic certainty chose to terminate the pregnancy. The decision is much more difficult for women carrying a fetus with less diagnostic or prognostic certainty. Insufficient data exists to determine how they handle these management decisions. Women tend to opt for abortion in cases of chromosomal abnormalities, regardless of the severity or certainty of the outcome. Women carrying a fetus with anatomic disorders with prognostic uncertainty or less severity choose to abort at lower rates. More research is needed to understand decision making processes.