THE VALIDITY OF "OVULATION POTENTIALS"

Abstract

By plotting isopotential contour patterns on human skin areas, it was difficult to locate properly on the surface a reference electrode which would be stable in potential. This instability, which may be in part, at least, related to emotional factors, made it impossible to obtain isopotential contours on preoperative patients near ovulation time. With the broad ligament as a reference electrode, direct measurements on ovaries in situ, during laparotomy within the estimated ovulation time, failed to show any marked potential gradients. The difficulty of maintaining the stability of a reference electrode on the skin surface offers in itself a rational explanation for the inconsistent results previously obtained in connection with the so-called "abdominovaginal sign" of ovulation. When adequate precautions were taken to rule out spurious readings, no marked changes could be demonstrated in daily finger-to-finger potentials of 2 groups of [female] subjects studied for about 9 consecutive wks. In [female][female] with normal menstrual habits, there was no evidence of cyclic potential changes between finger-tips that might be related to the occurrence of ovulation. The index fingers did not appear to possess any unique property when voltage readings obtained from them were compared with detns. made on other pairs of fingers. The observation that polarity was associated with relative activity (and possibly temp.) of 1 hand as against the other, as well as the high degree of similarity in direction of potential shifts of the 2 groups of $? studied simultaneously, pointed to a common environmental influence as a factor underlying the observed fluctuations, and suggested the investigation of temp. in relation to finger potentials. Temp. was shown to influence bioelectric potentials, the effect consisting of an increase in potential of the warmer area in a positive direction with respect to the cooler one. The relation of skin potential to the surface temp. was reasonably stable and reproducible within certain limits over the range from 12[degree]-46[degree] C. The change of potential with temp. was reversible; it was not affected by the sex, state of consciousness, or position of the subject. The results were similar whether fingers of the same or of opposite hands were tested, and, as shown by the rabbit expts., were apparently not dependent on sympathetic in-nervation of the areas studied. The evidence presented suggests that the mechanism through which temp. affects , potential may be bound up with changes in pH. If one assumes the thermal skin potentials to be due to a pH conc.-cell system and, on the basis of previous expts. relating temp. and pH, one calculates the values of E.M.F., the theoretical and observed figures agree closely. Bioelectric phenomena previously reported as related to ovulation are due primarily to cutaneous vascular conditions and possibly only remotely and to a slight degree to ovarian influence. Local changes in blood flow affect the focal temp., which in turn reacts on the focal pH, the fluctuations of which directly determine potential variations. Because the hormonal factor is only one of several affecting vascular phenomena, it is believed that potential changes recorded thus far cannot be attributed solely to ovarian activity, and that therefore the electric methods hitherto proposed are unsuitable for the detection of ovulation.