Natural family planning indicators of ovulation
Gross, B.A.
Clinical Reproduction and Fertility 5(3): 91-117
1987
ISSN/ISBN: 0725-556X PMID: 3322540 Document Number: 367515
Natural family planning (NFP) methods are based on the observation over the course of the menstrual cycle of specific signs and symptoms that result from changes in circulating blood levels of ovarian steroids, estrogen, and progesterone. There is a close association between the rise in progesterone, luteinizing hormone (LH), and estrogen peaks and ovulation. The basal body temperature (BBT) method is often incorporated in NFP methods that use 2 or more signs and symptoms of ovulation and is a simple, inexpensive way to determine the premenstrual infertile period. However, this method is not accurate in estimation of the day of ovulation, the postmenstrual infertile period, or the prediction of ovulation during postpartum lactational amenorrhea. The observation of changes in cervical mucus patterns can be used to define the probable fertile period of the menstrual cycle, but produces a wide range of days. The peak mucus symptom further can be used as a guide for the timing of blood or urine samples for the estimation of LH, estrogen, or progesterone. Changes in the morphology of the cervix, intermenstrual pain, vaginal bleeding, breast tenderness, vulval swelling, and backache have been incorporated into symptothermal NFP methods as secondary indicators of ovulation and can be used in conjunction with BBT and mucus observation. Under development are a number of electronic devices that will increase the ability to accurately determine the fertile and infertile phases of the menstrual cycle. A critical future need is more research on the reliability of NFP methods in breastfeeding women and the possibility that an increase in the volume of mucus may be a marker of the return of ovulation in lactating women.