PubMed1984
All natural family planning (NFP) methods are based on the determitnation of a woman's fertile period so that a couple may abstain from sexual relations or use a mechanical means of birth control during that time. Researchers are seeking more accurate methods of predicting the onset of ovulation in order to increase the effectiveness of NFP. A new device developed by Dr. Gebhard F.B. Schumacher, a fertility specialist at the University of Chicago who serves on FHI's Technical Advisory Committee, and Dr. Stepen J. Usala, a former medical student at the University's Pritzker School of Medicine, holds the promise of providing a new, cheap, and relatively simple way of predicting ovulation. Called a volumetric vaginal aspirator, the instrument allows women to measure their own vaginal fluid on a daily basis. In early studies of 7 women carefully studied over 18 menstrual cycles, a striking 3 fold to 30-fold increase in the volume of vaginal fluid occurred a few days before ovulation. Results from 12 more women for a total of 26 cycles confirmed the earlier studies. Blood samples were taken in order to measure the levels of estrogen, known to increase prior to ovulation, and luteinizing hormone, which peaks sharply on the day of ovulation, in the women studied. These confirmed that ovulation typically had occurred after the fluid volume increase. In addition, participants recorded their basal body temperature (BBT) upon awakening. Although the BBT does not predict ovulation, it frequently increases by 1/2-1 degree Fahrenheit after ovulation thus serving as an indicator of the end of the fertile period. The prototype of the vaginal aspirator is a disposable plastic syring marked at .05 milliliter intervals so that fluid levels can be easily measured. After the manufacturing process for the aspirator is perfected so that the instrument can be mass produced, Dr. Schumacher hopes that largescale clinical trials will be initiated in the US and abroad. The larger studies and an endocrine study are needed in order for effective rules to be developed for applying the method in either birth control or fertility enhancement. The vaginal aspirator could be useful not only for preventing unplanned pregnancy but also for aiding couples experiencing infertility to pinpoint the time that conception is most likely to occur. As an aid in birth control, the aspirator should have a success rate similar to or better than that of a diaphragm, Dr. Schumacher believes. Although the women testing the vaginal aspirator were ablet to use it without assistance, Dr. Schumacer emphasizes that some patient education will be necessary if it becomes commercially available. Fertility awareness teachers could incorporate it into their courses. Research on the volumetric vaginal aspirator has been supported by FHI and by Mothers' Aid Research Fund of Chicago Lying-In Hospital.
Clinical Laboratory Techniques↗