Natural family planning: suitability of the CUE method for defining the time of ovulation.

ABSTRACT

PIP: To evaluate the potential utility of the CUE method in natural family planning (NFP), this method was compared with a standard NFP technique, the Ovulation Method, in 39 cycles of 10 women from Monterrey, Mexico. All women had more than 2 years' experience with the Ovulation Method. In the CUE method, ovulation prediction is based on a peak in salivary electrical resistance and its confirmation by a rise in vaginal resistance as monitored by a hand-held electronic instrument attached to a specially designed sensor. The CUE method defined the fertile period of all 39 cycles adequately, while the Ovulation Method resulted in incorrect definition of the fertile phase in 4 (10%) of 39 cycles. The salivary peak predicted ovulation an average of 8 days in advance of its occurrence and the increase in vaginal readings in the periovulatory period was seen within 1 day of follicle collapse in all subjects. The duration of abstinence required by the CUE method would have averaged 9.0 +or- 1.5 days (range, 6-13 days). In contrast, the average duration of abstinence associated with the Ovulation Method was 11.0 +or- 2.9 days (range, 6-16 days). 82% of cycles monitored by the CUE method compared with only 53% of those monitored by the Ovulation Method would have required a period of abstinence of 10 days or less. The simplicity and objectivity of the CUE method, combined with its requirement for fewer days of abstinence, offer the potential for improving NFP compliance and continuation.