NaProTechnology for Infertility and Recurrent Miscarriage: A Review of Research

By: Jacob Steins, MD

Director’s Note: At FACTS, our focus is to share the science supporting the vital role of fertility awareness-based methods (FABMs) and restorative reproductive medicine (RRM) to equip our colleagues to help patients achieve their reproductive health goals. Former FACTS elective student, Dr. Jacob Steins, summarized research [1] assessing outcomes at a Canadian family practice treating patients with recurrent miscarriage and infertility using an RRM approach. The study by Tham et al was published in 2012 and is titled, “Natural Procreative Technology for Infertility and Recurrent Miscarriage: Outcomes in a Canadian Family Practice.” Dr. Steins compared these findings with a similar study from 2008 co-authored by one of the 2012 study authors, Dr. Joseph Stanford, who serves as a FACTS case study leader. Dr. Stanford will present about Transgenerational Reproductive Healthcare on Saturday, November 11 at our virtual conference, The Continuum of Women’s Healthcare. Register today!

Introduction

The Creighton Model of natural family planning (NFP) uses a standardized approach to tracking the biomarkers of the female cycle to empower women and couples with knowledge of their fertility. Natural Procreative Technology (NaPro technology) is a cooperative approach to women’s health concerns that enables Creighton-trained medical consultants to use information gathered through Creighton Model charts to identify and treat underlying causes of infertility. The research by Tham et al [1] summarized below assessed the outcomes (live birth and conception rates) of NaProTechnology in couples with infertility or recurrent miscarriage at a Canadian family practice to compare them to an earlier 2008 study by Stanford et al [2] which evaluated similar outcomes in an Irish general practice.

“Natural Procreative Technology (NaProTechnology) is a cooperative approach to women’s health concerns that enables Creighton-trained medical consultants to use information gathered through Creighton Model charts to identify and treat underlying causes of infertility.”

Methodology

The study [1] took place at a family medicine office in Canada from 2000 to 2006. It was a retrospective cohort study and involved 108 couples. Important demographic information for the test group included an average maternal age of 35.4, attempts to achieve pregnancy for an average of 3.2 years, and 18% of couples reporting ≥ 2 unexplained miscarriages. Regarding the test group, 80% was nulliparous, 22% had tried intrauterine insemination (IUI), and 8% had used some other form of assisted reproductive technology (ART), including in vitro fertilization (IVF).

Compared to the 2008 study in Ireland, [2] this population is similar in maternal age and percentage of nulliparous women. However, the Canadian group had a shorter duration of attempting pregnancy (3.2 years vs. 5.6 years) and a smaller percentage who had attempted to conceive using ART (8% vs. 33%). Also, the couples in the Canadian study had been trying to conceive for 6-12 months using a fertility awareness-based method (FABM) to correctly time intercourse. In the Irish study, all couples that had been attempting to conceive for less than a year were excluded. Therefore, it is reasonable to consider the Canadian cohort as a “more fertile” group than the test group in the Irish study.

Interventions in both studies were similar as they both employed NaProTechnology. Medical interventions included medications to improve cervical mucus, such as vitamin B6, guaifenesin or antibiotics, and medications to increase hormones in the luteal phase. In the Canadian study, 12% of patients were treated with a surgical option, and 8% of the couples that conceived had undergone surgery.

“Medical interventions included medications to improve cervical mucus, such as vitamin B6, guaifenesin or antibiotics, and medications to increase hormones in the luteal phase.”

Results

In the Canadian study, 38% of couples that started the study conceived and had a live birth within the test period of 2 years. With > 50% of couples dropping out of the study by the 2-year mark, life table analysis showed 66% of the couples that completed the study had a live birth.

Compared to the Irish study, this study revealed a higher crude birth rate (38% vs. 25.5%), higher life table analysis (66% vs. 52.8%), and a lower dropout rate (54% vs. 62.7%). Tham et al [1] compared their live birth rate result (66%) to another Canadian study published in 1995 [3] with a population of younger women (average 29.5 years) with similar duration of infertility (3.2 years). In the 1995 study, no intervention resulted in a 20% live birth rate, much lower than the 66% live birth rate achieved with NaProTechnology. This comparison of two Canadian studies with similar demographics shows the high effectiveness of NaProTechnology compared to no treatment. Compared to the Irish study, the authors agree their population was likely “more fertile” than the population in Stanford et al 2008, which likely contributed to their higher birth rate.

The authors noted IVF is approximately 50% successful in achieving live birth after 1 year of treatment, whereas this study showed a 1-year live birth rate between 32% (crude) and 45% (life table analysis). The authors cautioned against comparing IVF to NaPro, however, citing differences in demographics between studies.

Discussion

This study by Tham et al shows the potential for even a small Canadian family practice to improve live birth rates in couples that struggle with infertility. The live birth rate of 66% achieved through NaProTechnology offers hope for both couples and medical professionals.

“The live birth rate of 66% achieved through NaProTechnology offers hope for both couples and medical professionals.”

The authors cite a Cochrane review of IVF stating there is not enough conclusive evidence to consider IVF an effective option; there is no existing Cochrane review of NaPro. As compared to Stanford et al’s 2008 Irish study, it would be ideal to sort the results by demographic information such as maternal age, previous miscarriage, and previous ART to ascertain which patients experiencing infertility are most likely to benefit from NaPro.

Overall, this was an excellent study that showed the effectiveness of NaProTechnology in a general practice model, and which calls for more studies of NaPro in general practice as a cost-effective, low-risk option for couples experiencing infertility.

[1] Tham E, Schliep K, Stanford J. Natural procreative technology for infertility and recurrent miscarriage: outcomes in a Canadian family practice. Can Fam Physician. 2012;58(5):e267-e274.
[2] Stanford JB, Parnell TA, Boyle PC. Outcomes from treatment of infertility with natural procreative technology in an Irish general practice [published correction appears in J Am Board Fam Med. 2008 Nov-Dec;21(6):583]. J Am Board Fam Med. 2008;21(5):375-384. doi:10.3122/jabfm.2008.05.070239.
[3] Collins JA, Burrows EA, Wilan AR. The prognosis for live birth among untreated infertile couples. Fertil Steril. 1995;64(1):22-28.

ABOUT THE AUTHOR

Jacob Steins, MD

Jacob Steins, MD is a family medicine intern at David Grant Medical Center at Travis AFB, CA. He completed his medical training at the University of Colorado School of Medicine, and his undergraduate education at Vanderbilt University in Nashville, TN. He enrolled in the FACTS elective to gain a better understanding of natural family planning methods and manners in which to share these methods with patients so they feel more empowered over their health and reproductive decisions.