The science of fertility

New spouses exchange rings as Pope Francis, celebrates the marriage rite for 20 couples during a Mass in St. Peter’s Basilica at the Vatican in 2014. (CNS photo/Paul Haring)
 
February 8, 2018
Dr. Mary Davenport
 
NFP (natural family planning) relies on a woman’s own observations of her signs of fertility. By learning her unique biological markers, she can be empowered to both achieve and avoid pregnancy, as well as attaining a higher level of health throughout her entire reproductive life.
 
Modern NFP has come a long way from the old rhythm method of the 1930s. The calendar rhythm method calculated a woman’s fertile and infertile periods according to cycle length. However, the rhythm method has failure rates of 20 percent per year in preventing pregnancy because of variations in a woman’s cycle. In contrast, modern NFP relies on a woman’s own observation of her biomarkers such as cervical mucus and temperature. In 1968 Pope Paul VI in “Humanae Vitae” called upon “men of science” to develop a “secure regulation of births founded on the observance of natural rhythms.” In recent decades there has been a flourishing of the science of natural fertility by scientific organizations. Sometimes the names FAM or FABM (Fertility Awareness Methods or Fertility Awareness Based Methods) are used more or less interchangeably with NFP; NFP usually implies abstinence at the fertile time to prevent pregnancy.
 
For NFP/FAM to be effective, it is important to identify the fertile and infertile times in the cycle. The time of fertility begins with the rise in estrogen production from the ovary that occurs after the end of the menses. The cervix (mouth of the womb) opens somewhat, and cervical mucus become identifiable, more copious and eventually stretchy. The pituitary hormone LH rises and triggers the release of the egg from the ovary. Most NFP methods use a variation of these criteria to determine a “peak” day of the highest fertility. Following release of the egg, the ovary starts to secrete progesterone, which thickens the cervical mucus and raises the body temperature. If pregnancy does not occur, the hormones decline, temperature falls, and menses follow with the start of a new cycle.
 
The different methods vary by the signs that are followed and charted to determine the beginning and end of the fertile phase. Methods typically take into account the one-day survival of the egg after it is released, and sperm survival of up to five days in ideal conditions. The Billings, FertilityCare (Creighton) and Family of the Americas methods rely on observations of cervical mucus to determine the onset of fertility, and determination of the “peak” day to determine ovulation. The symptothermal method taught by Couple to Couple League can include several signs, but relies heavily on temperature rise. The Marquette Method relies on direct measurement of urinary hormones by dipsticks placed in a hand held computer (ClearBlue Fertility Monitor). The FEMM method is mainly a mucus method but users can incorporate other cycle characteristics.
 
Of equal importance to avoiding pregnancy is the value of NFP to facilitate achieving pregnancy. Up to 20 percent of couples have problems with infertility, so the cycle observations in NFP can be very helpful. Research has shown that cervical mucus and urinary measurement of the LH hormone are the most useful signs for detecting the timing of ovulation. NFP can be used in conjunction with medical and surgical therapies to heal disorders causing infertility. The most research on NFP and infertility has been done at the Pope Paul VI Institute in Omaha by Dr. Thomas Hilgers, correlating the FertilityCare NFP system with diagnosis and treatment of these disorders. Training programs in both hormonal and surgical therapies in NaProTechnology (Natural Procreative Technology) have educated hundreds of health care providers in effective therapies.
 
Mention must also be made of the many smartphone apps developed to prevent pregnancy and enhance fertility. They vary widely in quality, and some are inaccurate and misleading. The best apps are connected to well established NFP and FAM organizations. FACTS, an organization promoting all NFP methods and NFP education, recently did an excellent review of current apps (see below). Also, although apps can be useful for charting, no app or web site can replace an experienced NFP teacher in helping a couple navigate an NFP method.
 
All methods of NFP have the virtue of avoiding major and minor risks associated with artificial contraception. To name a few, NFP users avoid increased risk of serious cardiovascular complications such as stroke, pulmonary embolus and thrombophlebitis attributable to the pill and other hormonal contraception, as well has higher rates of breast cancer. Because they reject aggressive promotion of the IUD (intrauterine device), NFP users avoid uterine perforation, elevated rates of pelvic infections, and painful, heavy menses. Women who undergo surgical sterilization can experience heavy or irregular periods from hormonal abnormalities from the interruption of the blood supply to the ovaries, and undergo more hysterectomies. So in addition to avoiding problems associated with contraception and sterilization, NFP users are potentially graced with better physical health in addition to experiencing the spiritual, ethical and relational benefits of NFP with their spouse.
 
Dr. Mary Davenport is a physician in El Sobrante with more than 20 years of experience, a fellow of the American College of Obstetrics and Gynecology, medical director of the Magnificat Maternal Health and has specialties in holistic and integrative medicine and NaProTECHNOLOGY (Natural Procreative Technology). Mary L. Davenport, MD, MS, FACOG, CFCMC. https://drmaryldavenport.com.

 
Resources to consult with teachers and physicians for help with NFP
Billings: www.boma-usa.org
Couple to Couple League: www.ccli.org
Family of the Americas: www.familyplanning.net
FEMM: https://femmhealth.org/
 FertilityCare (Creighton): www.fertilitycare.org
 Marquette: https://nfp.marquette.edu/
 
Additional resources:
Naprotechnology: www.naprotechnology.com/
NFP Research: http://restorative-reproductive-medicine.com/
FACTS Review of Apps: www.factsaboutfertility.org/rating-of-fertility-apps-avoiding/
User’s experience: https://verilymag.com/2015/08/menstruation-charting-cycles-ovulation-fertility-awareness-creighton-model-reproductive-health-infertility-hormones