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Charlotte Lozier Institute

Phone: 202-223-8073
Fax: 571-312-0544

2776 S. Arlington Mill Dr.
Arlington, VA 22206

Maternal & Public Health

Planned Parenthood: Denying the Medical Science of Fertility Awareness

This is Issue 22 of the On Point Series.


Planned Parenthood data analyzed by the Charlotte Lozier Institute reveal that, over its past five years of annual reports, Planned Parenthood’s client numbers have declined by 20 percent  – from 3 million to 2.4 million.[i] This decline stands in stark contrast to Planned Parenthood’s success as a colossal moneymaker: indeed, while enjoying the protective tax status of a non-profit organization, Planned Parenthood has collected annual excess revenues of between $50 and $100 million over the past seven years.[ii] The decline in unique patients is mirrored in its smaller service counts across the board, with one notable exception – induced abortion holding steady at a third or more of the U.S. total.[iii]


Mega-donors such as foundations funded by Bill and Melinda Gates, George Soros, and Warren Buffett apparently have failed to keep up with the organization’s dwindling return on investment. Or they simply do not expect to see certain results from their contributions. In any event, several factors might account for Planned Parenthood’s shrinking roster of both clients and overall services despite hefty support from wealthy private donors. Planned Parenthood’s paltry return on a half-billion dollars[iv] in monetary support from both federal taxpayers and private funders may reflect – at least in part – the organization’s failure to keep up with advances in women’s health and reproductive science.


Witness, for example, recent claims by retiring Planned Parenthood President Cecile Richards that contemporary models of Natural Family Planning (NFP), based on fertility awareness, are “bringing back” the so-called “Rhythm Method.” During an interview with Tina Brown on December 4, 2017 at the Women in the World Texas Salon, Richards exclaimed it is “crazy!” that the current White House administration would seek to “redirect” federal support away from Planned Parenthood and its artificial birth control programs. Richards argued that supporting fertility awareness models of family planning is equivalent to going “back to the Rhythm Method.”   She further opined that support or use of Natural Family Planning by anyone who might wish to eschew chemical, mechanical, and other artificial methods is “completely insane.”[v]  


Such mockery reflects a woeful ignorance of major studies in women’s health and reproductive science that have been conducted since at least 1972, when Drs. Evelyn and John Billings of the Melbourne (Australia) University Department of Obstetrics and Gynecology published in The Lancet their findings on the “Symptoms and Hormonal Changes Accompanying Ovulation.”[vi]  This first of numerous publications was soon followed by more peer-reviewed science in the British Medical Journal,[vii] the Medical Journal of Australia,[viii] the American Journal of Obstetrics and Gynecology,[ix] and Acta Eur Fertil,[x] to name but a few.  Research on the Billings Ovulation Method of natural family planning and other models quickly revealed the precision with which women, couples and clinicians can identify the fertile phase of the female ovulatory cycle.  Unlike the so-called “Rhythm” or calendar method, which used information about previous cycle lengths to predict future days of fertility, Billings and modern fertility-awareness-based methods (FABMs) employ a growing body of science that enables women to easily track the signs of the female cycle to identify the potential days of fertility in real time.


Even before 1991, when Dr. John Billings published data constituting “The validation of the Billings ovulation method by laboratory research and field trials,[xi] research on fertility-awareness-based methods of NFP had proliferated widely. By the early 1980s Dr. Thomas Hilgers and colleagues were publishing in Obstetrics and Gynecology multiple articles on what has come to be known as the Creighton Model of Natural Family Planning and NaPro Technology.[xii],[xiii],[xiv],[xv] Hilgers and colleagues would further publish in the Journal of Reproductive Medicine,[xvi] the New England Journal of Medicine,[xvii] and other major peer-reviewed journals.[xviii]


Throughout the 1980s and 1990s, studies of fertility-awareness-based methods of NFP were not limited to the United States. In India, for example, a 21-month study looked at efficacy of the Billings Ovulation Method for 32,957 woman-months of data collected. Researchers found that 21 women experienced an unintended pregnancy while following the method correctly, resulting in an unintended pregnancy rate of only 1.1 per 100 users at 12 months.  With typical use, the unintended pregnancy rate was observed to be 10.5 per 100 women users at 12 months; meaning, the Billings Ovulation method showed an effectiveness rate of almost 99 percent with correct use and 90% with typical use.[xix]  More recent studies of the Sympto-Thermal method conducted in Germany showed even higher effectiveness rates.  In this 2007 study, data from 900 women with 17,638 cycles were analyzed and the unintended pregnancy rate was 0.43 per 100 women and 13 cycles with correct use and 1.79 per 100 women after 13 months, resulting in effectiveness rates of more than 99% with perfect use and 98% with typical use.[xx]


Planned Parenthood’s Richards is not the only recognized leader in women’s health to be remarkably ill-informed regarding the efficacy and appeal of fertility-awareness-based methods of natural family planning. A 2010 survey of gynecologists and family physicians showed only 3-6% of them had correct knowledge of the effectiveness of NFP methods with correct use.[xxi] Study findings shared in 2012 by Marguerite Duane, MD, MHA, FAAFP, et al. showed that among 120 family medicine residency programs surveyed, more than one-half of women’s health faculty members were not familiar with modern methods of NFP, and 25% of these programs did not include NFP in the women’s health curriculum.[xxii]


Using the Strength of Recommendation Taxonomy to review FABM studies published in peer-reviewed journals between 1980 and 2012, Duane and colleagues found that, with typical use, the effectiveness of individual methods ranged from 85.8% to 98.4%, based on high-quality studies. The researchers noted that commonly cited figures placing NFP effectiveness at 76% or worse reflect some data analysts’ practice of “lumping together” evidence-based, fertility-awareness methods with the clearly outdated “calendar” or “Rhythm” method.[xxiii] This oft-quoted, albeit misleading statistic, which is promulgated by the CDC, is also based on retrospective surveys, rather than prospective clinical trials of individual methods.


Publishing more recently in Frontiers in Medicine (2017), Drs. Peter Danis, Sally Kurz and Laura Covert observe that “[s]tudies of modern FABMs, including the Creighton Model Fertility Care System, the Marquette Model, and a symptothermal method, show that the typical unintended pregnancy rates can be comparable to other commonly used contraceptives.”[xxiv]


Danis and colleagues, like Duane and colleagues, have found that traditional medical school curricula in the U.S. have not addressed fertility-awareness-based methods (FABMs) of family planning, despite ever-increasing evidence of their effectiveness. The curriculum gap persists despite the fact that many women and couples find the methods to be healthful and empowering, and despite the fact that physicians with knowledge of these methods can use a woman’s chart to assist in the diagnosis and treatment of gynecologic problems including PMS, abnormal bleeding, and infertility.[xxv]


Fortunately, the tide is changing, aided in large part by demands from women themselves for greater choice and control over their reproductive health.  Concomitant with the “greening” of society as a whole, and explosive interest in environmentally friendly consumer products, we have seen the growth of organizations such as “Natural Womanhood” and the rejection of artificial birth control methods, by women’s health advocates such as Holly Grigg-Spall, author of Sweeting the Pill: or How We got Hooked on Hormonal Birth Control. Research by Dr. Victoria Jennings, et al., of the Georgetown University Institute for Reproductive Health, is being conducted partly in response by demands from more than 220 million women worldwide who wish to avoid the side effects associated with chemical and mechanical methods such as hormonal contraception, intrauterine devices, etc.[xxvi] Other researchers also note the desire of many women in the United States and globally to avoid common artificial methods that are now known to be potentially abortifacient.[xxvii] Thus it is fitting that the American Academy of Family Physicians Commission on Education now recommends that FABMs counseling be included as one of the core skills in Maternity and Gynecologic Care Recommended Curriculum Guidelines,[xxviii] and the American College of Obstetricians and Gynecologists recommends that even adolescents should learn to track cycles.[xxix] 


One brief cautionary note here: A growing number of electronic “Fertility Apps” for tracking cycles are being advertised today, some more effective than others. Clinical evidence shows that some apps are very effective in combination with proper training in FABMs. However – and as always – women and couples should consult the evidence, and not rely on mere marketing or personal “impressions” (Cecile Richards, please take note).[xxx]


Opportunities abound for clinicians and the public to learn more about FABMs: for example, in February 2018, FACTS, the Fertility Appreciation Collaborative to Teach the Science offered a Symposium for Healthcare Professionals and Students on Modern Fertility Awareness.  The learning objectives for the symposium were reviewed and the live activity was acceptable for up to 5.50 prescribed credit(s) by the American Academy of Family Physicians.  In addition to CME credits, advanced practice nurses and other eligible professionals could earn CEsCEUs respectively. Furthermore, FACTS offers live webinars on a monthly basis, including continuing medical education presentations for healthcare professionals and students and an introduction to FABMs for a general audience.


Ms. Richards and Planned Parenthood staff would be well advised to join other women and professionals in learning the facts.


Teresa Donovan, MPH, is an associate scholar with the Charlotte Lozier Institute.


[i] Donovan CA, Studnicki J. Planned Parenthood: “Irreplaceable” and “Lifesaving”? Charlotte Lozier Institute. On Point, Issue 17; 2017 August. Online at [accessed 2018 Jan 23]. See also Planned Parenthood Federation of America 2011-2012 Annual Report: [accessed 2018 Jan 30].

[ii] Bowman W. Business analysis cited by Peter Jesserer Smith. Planned Parenthood Evolution Underway Thanks to Influx of Private Donors. National Catholic Register. 2018 Jan 11. Online at [accessed 2018 Jan 23]

[iii] del Guidice, “Five Key Numbers from Planned Parenthood’s New Annual Report,” The Heritage Foundation, The Daily Signal, 2018 Jan 5, Online at

[iv] Planned Parenthood Federation of America. Planned Parenthood Annual Report 2016. See The report is for the fiscal year ending June 30, 2016. The government funding figure includes both federal and state receipts. See also oq=Planned+Parenthood+Action+Fund+%2415+million+2016&gs_l=psyab.3…4571.5355.0.6251.….0…1.1.64.psyab..1.0.0.gel2B1NKFBE.

[v] Women in the World. “Cecile Richards says ‘#MeToo’ onstage at the Women in the World Dallas Salon.” [accessed 2018 Jan 22].  Richards’ assertion that support or use of Natural Family Planning is “completely insane” appears at or near video minute 3:363:38

[vi] Billings EL, Brown JB, Billings JJ, Burger HG. Symptoms and hormonal changes accompanying ovulation. Lancet. 1972 Feb 5;1(7745):282-4. PubMed PMID: 4109930.

[vii]Billings JJ, Bennett LA. Quality of cervical mucus and Huhner’s test. Br Med J. 1978 Aug 26;2(6137):640. PubMed PMID: 581269; PubMed Central PMCID: PMC1607518.

[viii] Billings JJ. Natural family planning. Med J Aust. 1978 Oct 21;2(9):436. PubMed PMID: 732740.  Also Billings JJ. Ovulation method of contraception. Med J Aust. 1981 Jan 10;1(1):45-6. PubMed PMID: 7207299.

[ix] Billings JJ. Natural family planning methods. Am J Obstet Gynecol. 1982 May 1;143(1):1145. PubMed PMID: 7081306. Also Billings JJ. Two methods of natural family planning. Am J Obstet Gynecol. 1980 Mar 1;136(5):697-8. PubMed PMID: 7355954. Also Brown JB, Blackwell LF, Billings JJ, Conway B, Cox RI, Garrett G, Holmes J, Smith MA. Natural family planning. Am J Obstet Gynecol. 1987 Oct;157(4 Pt 2):1082-9. PubMed PMID: 3314524.

[x] Billings JJ. The validation of the Billings ovulation method by laboratory research and field trials. Acta Eur Fertil. 1991 Jan-Feb;22(1):9-15. PubMed PMID: 1746210.

[xi] Ibid.

[xii] Hilgers TW, Prebil AM. The ovulation method–vulvar observations as an index of fertility/infertility. Obstet Gynecol. 1979 Jan;53(1):12-22. PubMed PMID: 760010.

[xiii] Hilgers TW, Bailey AJ. Natural family planning. II. Basal body temperature and estimated time of ovulation. Obstet Gynecol. 1980 Mar;55(3):333-9. PubMed PMID: 7360431.

[xiv] Hilgers TW, Daly KD, Prebil AM, Hilgers SK. Natural family planning III. Intermenstrual symptoms and estimated time of ovulation. Obstet Gynecol. 1981 Aug;58(2):152-5. PubMed PMID: 7254726.

[xv]  Hilgers TW, Bailey AJ, Prebil AM. Natural family planning IV. The identification of postovulatory infertility. Obstet Gynecol. 1981 Sep;58(3):345-50. PubMed PMID: 7266954.

[xvi] Hilgers TW, Daly KD, Prebil AM, Hilgers SK. Cumulative pregnancy rates in patients with apparently normal fertility and fertility-focused intercourse. J Reprod Med. 1992 Oct;37(10):864-6. PubMed PMID: 1479570. See also Hilgers TW, Stanford JB. Creighton Model NaProEducation Technology for avoiding pregnancy. Use effectiveness. J Reprod Med. 1998 Jun;43(6):495-502. PubMed PMID: 9653695.

[xvii] Hilgers TW. Pregnancy and the timing of intercourse. N Engl J Med. 1996 May 9;334(19):1267; author reply 1267-8. PubMed PMID: 8606727.

[xviii] Work by Dr. Hilgers and his colleagues has appeared in Fertility & Sterility, the Journal of Ultrasound Medicine, the Journal of Laparoendoscopic Surgery, Linacre Quarterly, as well as Issues in Law and Medicine, et al.

[xix]Bhargava H, Bhatia JC, Ramachandran L, Rohatgi P, Sinha A. Indian Council of Medical Research Task Force on Natural Family Planning: Field trial of billings ovulation method of natural family planning. Contraception 53(2): 69-74. PMID:  8838482.



[xx]Frank-Herrmann P, Heil J, Gnoth C, Toledo E, Baur S, Pyper C, Jenetzky E, Strowitzki T, Freundl G.  The effectiveness of a fertility awareness based method to avoid pregnancy in relation to a couple’s sexual behaviour during the fertile time: a prospective longitudinal study.  Hum Reprod. 2007 May;22(5):1310-9.  Epub 2007 Feb 20. PMID: 17314078.

[xxi] Choi J, Chan S, Wiebe E.  Natural Family Planning: Physicians’ Knowledge, Attitudes, and Practice J Obstet Gynaecol Can 2010;32(7):673–678. PMID: 8838482.

[xxii] Gordon L, Motley RJ, Duane M, et al. Survey of fertility awareness methods incorporated into women’s health curricula in family medicine residency programs. Oral presentation at: 2012 Family Medicine Education Consortium Northeast Region Meeting; September 27–30, 2012; Cleveland, Ohio. See article and note 6 at

[xxiii] Duane M, Motley R, Manhart M. Physicians Need More Education About Natural Family Planning. Am Fam Physician. 2013 Aug 1;88(3):158-159. PMID: 23939690. Online at [accessed 2018 Jan 28]. Cites Manhart MD, Duane M, Lind A, et al. Fertility awareness-based methods of family planning: A review of effectiveness for avoiding pregnancy using SORT. Osteopathic Fam Physician. 2013;5(1):2–8. Online at

[xxiv] Danis P, Kurz S, Covert L. Medical Students’ Knowledge of Fertility Awareness-Based Methods of Family Planning.  Front Med (Lausanne). 2017 Jun 1;4:65. doi: 10.3389/fmed. 2017.00065. PMID: 28620604. PMCID: PMC5451495.

[xxv] Danis et al. cite:

  1. Manhart MD, Duane M, Lind A, Sinai I, Golden-Tevald J. Fertility awareness-based methods of family planning: a review of effectiveness for avoiding pregnancy using SORT. Osteopath Family Physician (2013) 5(1):2–8.10.1016/j.osfp.2012.09.002 [Cross Ref]
  2. Pallone SR, Bergus GR. Fertility awareness-based methods: another option for family planning. J Am Board Fam Med (2009) 22(2):147–57.10.3122/jabfm.2009.02.080038 [PubMed] [Cross Ref]
  3. Smoley BA, Robinson CM. Natural family planning. Am Fam Physician (2012)

86(10):924–8. [PubMed]

[xxvi] Simmons RG, Shattuck DC, Jennings VH. Assessing the Efficacy of an App-Based Method of Family Planning: The Dot Study Protocol. JMIR Res Protoc. 2017 Jan 18;6(1):e5. doi: 10.2196/resprot.6886. PMID:  28100441.

Natural Womanhood is woman’s health literacy organization based in San Antonio, Texas:

In their documentary “Sweetening the Pill,” veteran filmmakers Ricki Lake and Abby Epstein investigate the underreported dangers of hormonal contraception and women’s increasing rejection of such products:  See also

[xxvii] de Irala J, Lopez del Burgo C, Lopez de Fez CM, Arredondo J, Mikolajczyk RT, Stanford JB. Women’s attitudes towards mechanisms of action of family planning methods: survey in primary health centres in Pamplona, Spain. BMC Womens Health. 2007; 7: 10. Published online 2007 Jun 27. doi: 10.1186/1472-6874-7-10. PMCID: PMC1924844.

Dye HM, Stanford JB, Alder SC, Kim HS, Murphy PA. Women and postfertilization effects of birth control: consistency of beliefs, intentions and reported use. BMC Womens Health. 2005; 5: 11. Published online 2005 Nov 28. doi: 10.1186/1472-6874-5-11. PMCID: PMC1325031.

[xxviii] American Academy of Family Physicians. Recommended Curriculum Guidelines for Family Medicine Residents: Women’s Health and Gynecologic Care. eprint282_Women.pdf   Updated August 2016. Accessed 2018 Jan 23.

[xxix] The American College of Obstetricians and Gynecologists. ACOG Committee Opinion No. 651: Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign. Obstet Gynecol. 2015;126(6):e143-6.  Accessed October 2, 2017.

[xxx] Duane M, Contreras A, Jensen ET, White A. The Performance of Fertility Awarenessbased Method Apps Marketed to Avoid Pregnancy. J Am Board Fam Med. 2016 Jul-Aug;29(4):50811. doi: 10.3122/jabfm.2016.04.160022. PMID: 27390383.


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