The temporal relationship between vaginal fluid volumes obtained with the Rovumeter vaginal aspirator and the fertile phase of the cycle.

Recent trends in family planning demonstrate an increasing interest in natural methods of birth regulation. In their present form, however, these methods are highly subjective and individualistic. A further trend in fertility programmes has been a very rapid development of technological methods to detect fertility in the female cycle, some of which could possibly benefit natural family planning users. One such technique--that of changing volumes of cervico-vaginal fluid (CVF), which is a mixture of cervical mucus and vaginal transudate--has been tested in a pilot study to ascertain its reliability to demarcate the fertile phase of the cycle. Results show that in all cycles tested, it is possible using the Rovumeter aspirator to detect the beginning of the fertile phase by rapidly increasing volumes of CVF; this volume reaches a peak approximately 1 day before ovulation detected by ultrasound and demonstrates an abrupt fall after ovulation and the onset of the infertile phase. From the results of this pilot study, we believe that, by the use of suitable algorithms and larger studies, it should be possible to develop a CVF volume method which could be offered as an objective alternative method for users of natural family planning and programmes.