Last week I began a discussion about an article in the January edition of Obstetrics & Gynecology entitled, “Relationship Between Ultrasound Viewing and Proceeding to Abortion.” The authors found that in Planned Parenthood clinics in LA, the voluntary viewing of ultrasounds by patients seeking abortions appeared to dissuade a very small percentage from continuing on to abortion. Overall there appeared to be 0.6% absolute risk reduction (99.0% of those who did not view the ultrasound, and 98.4% of those who did, proceeded to abortion).
This is a small reduction indeed. If we calculate the “number needed to treat,” or NNT (we might use the term “number needed to scan” in this setting), we find that it took 151 ultrasounds to cause one woman to change her mind. But how should we interpret these results? That is, how should we assign a value to raw numbers?
If one considers that an ultrasound could be a “screening” test to find that cohort of patients who would change their minds about abortion, and that the outcome is a saved human life, then the numbers become quite appealing. In other words, if the number needed to treat (or scan) to save one life is 151, then scanning is an outstanding intervention. In contrast, nine times as many women aged 50 to 59 years must be screened for breast cancer with mammograms to achieve the same number of lives saved. One could try to calculate in the relative risks to women’s lives from abortion vs. term pregnancy, but these numbers are quite small compared to the relative risk to the fetus’s life from abortion vs. term pregnancy.
Is not one human life gained worth the time, effort, and cost of 151 ultrasounds? As a physician I perform or order countless tests, including many as part of standard prenatal screening, with much slimmer hopes of benefit. And, with succeeding generations of lives produced from each fetus saved, the NNT drops dramatically. For those opposed to abortion, the statistics seem to provide little hope for a significant change of minds that they would hope for. But whenever I observe the dramatic miracle of a single birth I see an outcome grand enough to justify the effort.
It is a fundamental flaw of the research to impose a moral equivalency on all outcomes. It is not simply a matter of weighing 150 choices in one direction for every one choice in another—it is the weighing one human life gained vs. all other outcomes. Isn’t the saving of lives what we’re here for? Or do physicians direct their lives’ work toward simply accumulating “choices” satisfied?
Next post will discuss the ethical conclusions made by the authors, who raised concerns about risks of viewing the ultrasound itself.