Methods · Sympto-Thermal Method
Davis MS, 1992 · NAACOGS Clin Issu Perinat Womens Health Nurs
Natural family planning includes the calendar (rhythm), basal body temperature, ovulation (mucus), and sympto-thermal methods. Reliability of such methods often is underestimated, but effectiveness of various methods has been reported. Correct understanding and use of proper techniques, primarily abstinence during fertile periods, is imperative for effectiveness. New methods being studied may heighten awareness of fertile times and shorten required periods of abstinence or use of back-up methods.
Methods · Sympto-Thermal Method
Flynn AM, 1984 · Clin Obstet Gynaecol
Reliable indicators to detect the fertile and infertile phases in the menstrual cycle are now available, largely due to the intensive scientific research into fertility over the past decade. This means that couples who follow the rules of the different NFP methodologies have a highly effective means of birth control, without the introduction of hormones, chemicals or devices into the body. New scientific techniques can be expected within the next couple of years which will simplify the detection of the fertile phase and hopefully help to elucidate the grey area of the early fertile days, where most of the unplanned pregnancies occur. Fertility awareness by both partners is an important positive contribution to the whole sexual relationship and emphasizes that NFP is an educational delivery system rather than a technological one. The modification of sexual behaviour and the motivation of both partners for the successful use of NFP may initially present a problem to some couples. On the other hand, many partners find the discipline enhances their sexual relationship and dialogue. Whatever the motivation, today more and more couples are happier to be in autonomous control of their bodies and their fertility.
Methods · Calendar and Rhythm Methods
Zufferey MM, 1986 · Ther Umsch
Risks of 5 natural family planning (NFP) methods are compared. The main risk of these methods is the risk of pregnancy stemming from method failure, errors in instruction, error in application of the method, and failure to observe abstinence during the entire fertile period. The calendar rhythm method, the oldest NFP method, is based on calculation of likely fertile days in the preceding 6-12 menstrual cycles. The method is seldom taught at present because of its high failure rate, but it continues to be used, often by individuals with an incomplete understanding of the calculations. The principle of the basal body temperature method is well known. The thermal shift affirms the beginning of the infertile period but does not allow prediction of ovulation. Instructions provided by different organizations to identify the third day of the hyperthermal plateau are not standardized; the various interpretations applied to the same cycle do not necessarily lead to identification of the same day as the start of the infertile period. Comparisons of efficacy between methods are therefore difficult. Well-conducted prospective studies have demonstrated high theoretical efficacy, but failure rates in practice appear to be higher. Women often do not know how to interpret a temperature curve correctly, and the curve may be influenced by illness, sleeping late, a change of life style or thermometer. Some authors have reported that 3-20% of ovulatory cycles have monophasic temperature curves. The temperature method requires lengthy abstinence lasting until the third day of higher temperature, which may create conflicts in some couples. To ease the difficulties of interpretation of the temperature method, a Swiss architect developed an electronic thermometer programmed according to rules of the calendar rhythm method for cycles of 19-39 days. The woman's 6 most recent cycle lengths remain in the memory to indicate probable infertile days. Although no formal evaluations have appeared in the literature on the Bioself thermometer, the method appears to entail risks including registration of incorrect temperature due to humidity or rundown batteries, and inadequate programming to identify the safe period. The Billings or cervical mucus method is based on observation by the woman of the thickness, wetness, and other characteristics of mucus secretions in the vulva to predict ovulation. Various studies have shown high theoretical efficacy but practical efficacy is lower. Vaginal infections, some ovarian pathologies, and postpartum hormonal changes are among factors that can alter mucus patterns. The method does not confirm ovulation, and false "peak days" may occur. The symptothermal method is based on all the principles of the cervical mucus and temperature methods as well as autopalpation of the cervix and any other signs of ovulation. Effectiveness rates are high. In general pregnancy risks are the same as those for the cervical mucus and temperature methods. A theoretical heightened risk of abortion or fetal malformation common to all the methods due to fertilization of aging gametes has not been definitively evaluated. Another possible risk results from timing of abstinence at the phase of the menstrual cycle when the woman's sexual desire is likely to be greatest.
Methods · Billings Ovulation Method
Jones M, 1978 · Fertil Contracept
There are currently signs that more women are considering the natural family planning methods as an alternative to medical contraception. In response to this revival of interest, the World Health Organization is now conducting field work on 'natural' family planning methods in New Zealand, the Philippines, India, California, and Columbia and is also preparing a teaching package to be pilot tested in several countries. The natural methods of family planning are all based on the woman correctly ascertaining the pattern of her natural menstrual cycle and abstaining from sexual intercourse during the fertile time. In most women this means that there are 2 "safe periods" - at the beginning of the 28-day cycle until a few days before ovulation and at the end of the cycle from 3 or 4 days after ovulation has occurred. Originally, the "safe period" was taught by the calendar method, which involved a woman carefully plotting her menstrual cycle over a period of six months to a year and making calculations as to the shortest possible and longest possible cycle length, and thus the likely time of ovulation. A more accurate measure is to actually find out the point of ovulation by measuring basal body temperature. With this method the woman must take her temperature every morning immediately upon waking, before rising, smoking, eating or drinking. The Billings' ovulation method is the method now becoming increasingly popular. The method involves noticing the natural changes in the body over the whole menstrual cycle, particularly the quantity and quality of the cervical mucous. 1 new aid for pinpointing the exact time of ovulation is the Ovutime Fertility Detection System developed at Harvard University Medical School and the Massachusetts Institute of Technology. In the long-term, the rhythm method is unlikely to prove the answer to the problem of fertility regulation for the modern woman.