Natural family planning (NFP)
Part 2- Summary of NFP methods and effectiveness
1. Calendar Rhythm
Based on a woman’s previous menstrual cycles, the fertile days begin at shortest previous cycle minus 19 days and end at longest previous cycle minus 11 days.
Strength: ease of use, low cost
Weakness: only works for women with regular cycles
Perfect use pregnancy rate: 5%
Typical use pregnancy rate: 9-47%
2. Standard Days Method
Women who typically have 26-32 days consider themselves fertile during days 8-19 of the cycle.
Strength: ease of use, consistent month to month
Weakness: only for women with cycles 26-32 days
Perfect use pregnancy rate: 5%
Typical use pregnancy rate: 12%
3. Two-Day Method
If a woman has noticed any vaginal discharge today or yesterday, she considers herself fertile today.
Strength: ease of use, can be used by women with irregular cycles or no menstrual bleeding.
Weakness: cannot be used if a woman has a continuous vaginal discharge
Perfect use pregnancy rate: 4%
Typical use pregnancy rate: 14%
4. Basal Body Temperature Method
When a woman’s basal (first morning) temperature rises at least 0.5 degrees Fahrenheit (0.2 degrees Celsius) for 3 days compared to the previous 6 days, the fertile days are over.
Strength: Highly effective.
Weakness: Applies only to women who are ovulating consistently. Most restrictive method, because it defines only about 10 days of infertility in each cycle.
Perfect use pregnancy rate: <1%
Typical use pregnancy rate: 2-20%
5. Sympto-Thermal Method
The beginning of the fertile days according to onset of mucus discharge, calendar calculation, or cervix palpation; end of fertile days according to temperature rise cross-checked by end of mucus discharge.
Strength: Multiple symptoms to cross check.
Weakness: Most complex of NFP methods. Need for personal instruction.
Perfect use pregnancy rate: <1%
Typical use pregnancy rate: 3-20%
http://www.ccli.org/
http://www.nwfs.org/
http://www.ovusoft.com
6. Billings Ovulation Method
Days with vaginal discharge and three days after the mucus Peak Day are considered fertile. (For continuous vaginal discharge, a base infertile pattern is defined that is treated similarly to days without vaginal discharge.)
Strength: Extensive international organization for teaching; has been successfully applied and demonstrated in many different cultural and socioeconomic settings.
Weakness: Need for personal instruction.
Perfect use pregnancy rate: 1%
Typical use pregnancy rate: 8-22%
http://www.woomb.org/
7. Creighton Model FertilityCare System
Days with vaginal discharge and three days after the mucus Peak Day are considered fertile. (For continuous vaginal discharge, a base infertile pattern is defined that is treated similarly to days without vaginal discharge.)
Strength: Highly standardized observation and teaching system. The basis for medical applications for infertility and gynecologic problems (natural procreative technology, or NaPro Technology).
Weakness: Requires most intense instruction schedule of any NFP method (5 or more visits in the first year of use).
Perfect use pregnancy rate: <1%
Typical use pregnancy rate: 14-30% (Unlike other NFP studies, “typical use� pregnancy rates in Creighton Model System studies include planned pregnancies.)
http://naprotechnology.org/
8. Lactational Amenorrhea
Women who are exclusively breastfeeding and within 6 months after birth consider themselves infertile. This means no bottle supplements at all. Also, if a woman’s period returns, this method no longer applies.
Strength: Ease of use (if totally breastfeeding)
Weakness: Applies only to a narrow time frame
Perfect use pregnancy rate: 1-2%
Typical use pregnancy rate: Unknown
http://www.lalecheleague.org/ba/Aug93.html
http://www.fhi.org/en/RH/Pubs/booksReports/LAMconsensus.htm
9. Persona®
Based on urinary estrogen and LH measurement via electronic device that is available in Europe, but not in USA.
Perfect use pregnancy rate 6-12%
Typical use pregnancy rate 29%
http://www.g-h-o.co.uk/persona.htm
10. Marquette Method
Based on urinary estrogen and LH measurements (based on a device that is available in the USA), with addition of mucus observation or basal body temperature.
Effectiveness is unknown, there are studies in progress
http://www.marquette.edu/nursing/nfp/
Comparisons to other reversible family planning methods:
Comparisons are made with caveat that there are no randomized trials and groups of users differ. As noted, difference in groups of users will affect typical use pregnancy rates for any reversible method.
A. Condoms
Perfect use pregnancy rate: 2%
Typical use pregnancy rate: 15%
B. Spermicides
Perfect use pregnancy rate: 18%
Typical use pregnancy rate: 29%
C. Oral contraceptives
Perfect use pregnancy rate: <1%
Typical use pregnancy rate: 8%
I found this interesting.
Seems to me that if you have sex there is a chance that you will get pregnant even if you use one of the methods of BC above. Reconfirms the churchs teachings on pre-marital sex…..