When a real-time recording technology is introduced into a situation that previously depended on manual records, the amount of data recorded increases dramatically. A record that displayed fetal heart rates taken at 15- to 30- minute intervals and recorded at some later time by a nurse is suddenly displaced with a fetal heart monitor that generates a paper tape with a continuously recorded fetal rate. Previously unnoted short-term irregularities are now carefully preserved. Whenever an injured child is born, the fetal heart rate record will be scanned by plaintiff’s counsel in the hopes of finding some deviation from normal that can be used to build a case against the delivering physician. This search is seldom in vain because of the second problem that leads to secondary liability: data with ambiguous interpretations.

Fetal heart rate is monitored in women in labor to determine if the fetus’s well- being is compromised. If the fetus is in trouble, the usual response is an emergency Cesarean section. Fetal heart monitors provide a reasonably accurate record of fetal heart rate. The problem is in interpreting these records. Dramatic, prolonged slowing of the fetal heart rate clearly means trouble. But many other patterns of fetal heart rate irregularities do not so clearly point to trouble that they unambiguously call for an emergency Cesarean section with its attendant risks and costs. On the other hand, if the infant is born damaged, such irregularities will seem very important in hindsight. In a strict sense, much of what a fetal heart monitor records is not information: it does not reduce the physician’s uncertainty over the selection and timing of Cesarean sections.

In retrospect, the major factor in secondary litigation from fetal heart monitors may be the third factor: the shift in patient care patterns that accompanied the routine use of the devices. The traditional method of determining fetal fitness was to auscultate the fetal heart with a stethoscope. This requires that someone closely observe the laboring woman at frequent intervals. The premise of electronic fetal monitoring was that the heart rate itself was the critical parameter in this evaluation. It may be that other observations that accompanied this direct and intimate contact with the patient provided a necessary context for interpreting the significance of changes in the heart rate. As physicians and nurses came to rely on fetal heart monitors, they could evaluate the fetus by looking at the monitor strip and ignore the patient entirely. It is also likely that these cursory evaluations decreased in frequency because the monitor allowed the retrospective review of the heart rate. While it is difficult to sort out the causal factors, the most recent research indicates that the use of fetal monitors increases the probability of adverse fetal outcomes.