Keep in mind that both types of CVS are relatively recent techniques, so there is still less known about their long-term safety and accuracy. Dr. Wilson suggests attending a center where each doctor has done a minimum of 50 CVS per year.

A large American study of the method showed the same rate of fetal loss as for amniocentesis but higher rates of cramping (22 percent), spotting (33 percent) and fluid leakage. However, a large Canadian study showed a higher rate of miscarriage, and possible higher rate of stillbirth following the procedure. For every 200 women having CVS there would be five more miscarriages than with amniocentesis. There is also a higher incidence of uncertain results, and ten percent of the time a woman will have to get an amniocentesis to clarify the results.

In spite of all these drawbacks, Canadian women participating in the study, felt they would opt for CVS in the future. One advantage appears to be that women can be relaxed, and become more attached to their babies six to eight weeks before women who are waiting for their amniocentesis results.

Recent research showed a possible increased risk of fetal limb abnormalities following CVS, especially if the CVS was done before ten weeks of pregnancy. The risk goes from one in 2,000 before CVS to one in a 1,000 after CVS.

An Ethical Dilemma

Many unanswered questions remain about amniocentesis and chorionic villi sampling:

• Does amniocentesis or CVS give a woman more choice than she wants?

• Does the availability of amniocentesis and CVS conflict with our desire to build a better world for the handicapped?

• What are the effects of early ultrasound on the baby?

• Does amniocentesis or CVS cause any long lasting and subtle physical or psychological damage to the fetus?

• Should only perfect fetuses be saved?

• How can we make late abortions less traumatic for women who choose them?

• How can we educate women on the social as well as the medical facts of what it means to raise a child with Down's Syndrome in this society?

Further Reading

THE TENTATIVE PREGNANCY, PRENATAL DIAGNOSIS AND THE FUTURE OF MOTHERHOOD, by Barbara Rothman (1986). This book discusses the difficult choice of amniocentesis and the meaning for mothers who choose it or who don't choose it. She also explores mother's feelings about choosing to abort the baby or making the opposite choice.

BIRTH OVER THIRTY (revised 1985), by Sheila Kitzinger. This book thoughtfully and reassuringly reviews the joys and challenges facing the older mother.

EVERY WOMAN'S GUIDE TO TESTS DURING PREGNANCY (1986), by the Coalition for Medical Rights of Women, 2845 24th St, San Francisco, CA, 94110. 415-826-4401.