Conception and the Fertile Window: It’s All in the Timing
By: Amy Cooper, DO
Director’s Note: At FACTS, our mission is to educate current and future medical professionals about an expanded array of options for women’s healthcare, which includes the important role of fertility awareness-based methods (FABMs) for family planning. Dr. Amy Cooper, a family medicine resident and former FACTS elective participant, summarized a 2018 article highlighting the value of educating primary care physicians about the fertile window and the fertility-tracking devices utilized by various methods, such as the ClearBlue Fertility Monitor (CBFM). Published in Frontiers in Medicine, the article is titled, “Achieving Pregnancy Using Primary Care Interventions to Identify the Fertile Window.” [1] To support our efforts to educate students about FABMs, please give to FACTS today. Thank you!
Introduction
Primary care clinicians are at the frontline of the healthcare system. These medical professionals must know how and when to address a patient’s specific needs, wants, and goals. When it comes to fertility and family planning, primary care medical professionals can play a pivotal role. When a couple is attempting to achieve pregnancy, the typical response from many health professionals can be described as a “free-for-all” approach, consisting of counseling the couple on frequent intercourse with the caveat that an infertility workup would commence after 12 months of frequent intercourse without successful conception.
There are many reasons why patients do not want to wait 12 months to begin a more thorough investigation, including finances, age, and health circumstances. When a couple expresses a desire to conceive, primary care medical professionals can begin by educating them about targeting intercourse to the fertile window. The 2017 study [1] by Bouchard et al summarized below aimed to determine the effectiveness of achieving pregnancy by timing intercourse in the days of a woman’s fertile window, which can be identified by cycle tracking.
“When a couple expresses a desire to conceive, primary care medical professionals can begin by educating them about targeting intercourse to the fertile window.”
Methodology
The study by Bouchard et al was a prospective 24-cycle effectiveness study. [1] Study participants were recruited from 2008 through 2015 and consisted of North American women ages 20-43 years old. Many of them were found in a fertility forum online. Participants were required to have had at least one menstrual cycle charted using the Marquette Model. Their fertility status was not addressed in the inclusion criteria, so women who were previously pregnant as well as those who had never been pregnant were all included in the study. Overall, 256 women met the inclusion criteria and agreed to participate in the study.
Using an online fertility tracking service, women were able to chart their cycles using hormonal fertility markers with a ClearBlue Fertility Monitor, cervical mucus monitoring, or both. Users of the online tracking service were notified of the potential for pregnancy once the post-ovulatory phase, or luteal phase, was extended past 19 days. This prompted the users to complete an online self-evaluation. Nursing staff reviewed the charts to confirm whether intercourse was targeted to the fertile window.
The rate of positive pregnancies was determined by using survival analysis. Pregnancies were reviewed to identify those that resulted from “correct use” of the tracking system, which was defined as intercourse targeted to the fertile window. Chi-square analysis was used to determine differences in pregnancy rates between the varying methods used to chart (hormonal monitoring via CBFM only, mucus tracking only, or both).
Results
The CBFM-only group increased from 99 pregnancies per 100 women at 12 months to 100 pregnancies per 100 women at 24 months. The rates of pregnancy for the group that tracked both resulted in 79 pregnancies per 100 women, and the mucus-only tracking group did not have enough power for the 24-month analysis.
Of the 256 participants, the total number of pregnancies was 150, or 59% of the study population. Broken down by time in months, there were pregnancies in 50 per 100 women after 3 cycles, 73 per 100 at 6 months, 75 at 9 cycles, and 78 of 100 women at 12 months. After 24 months of tracking, there were pregnancies in 86 per 100 women.
Discussion
Bouchard et al sought to determine the effectiveness in achieving pregnancy by using methods of natural family planning, including hormonal biomarker tracking and mucus charting. [1]They compared the outcomes to the 85 per 100 pregnancies from unprotected intercourse identified by Trussell in a 2011 study, [2] and to the 92 per 100 pregnancies at 12 months achieved through timed intercourse and identified by Gnoth et al. [3] The secondary intent was to identify how primary care medical professionals can include natural family planning methodology in shared decision-making discussions as soon as patients express a desire to conceive.
This study [1] found 86 pregnancies per 100 women at 24 months of tracking, affirming the utility of cycle tracking in patients attempting to conceive. Although the pregnancy rates are lower than the previous studies, it’s possible this population had higher rates of subfertility, since they were pursuing additional information via an online fertility forum. Of note, the CBFM-only group reached 100 pregnancies per 100 women by the 24-month analysis, out-performing the other two study groups.
“This study found 86 pregnancies per 100 women at 24 months of tracking, affirming the utility of cycle tracking in patients attempting to conceive.”
The study concludes fertility monitors may be useful for couples attempting to conceive by enabling them to time intercourse to the fertile window. Nevertheless, there is still room for further research and clarification. One weakness identified by the authors is the uncertainty that remains regarding whether focused intercourse results in a shorter time to pregnancy compared to random acts of intercourse throughout the cycle. They acknowledged the need for future large randomized controlled studies to address this uncertainty. Also, the study only used the ClearBlue Fertility Monitor, leaving room for further research to compare the effectiveness of other brands and devices that monitor fertility. Although there is no identified conflict of interest, there remains the possibility of bias for the ClearBlue monitoring system, pointing to the need for comparisons.
Primary care medical professionals can easily gain competency in the use of fertility tracking devices, and the ideal time to be exposed to these tools and approach is during medical training. Rather than having to wait 12 months before meeting current definitions of infertility, patients can learn about fertility tracking methods from their primary care or Ob-Gyn physicians as soon as they express interest in pursuing pregnancy. Such a proactive approach would minimize wait times couples may have to endure before meeting criteria for an infertility evaluation and referral to discuss further options to address underlying causes of infertility.
“Primary care medical professionals can easily gain competency in the use of fertility tracking devices, and the ideal time to be exposed to these tools and approach is during medical training.”
The authors discussed key recommendations primary care professionals may provide to optimize a couple’s natural fertility. Lifestyle recommendations include the Harvard fertility diet, multivitamins, avoiding tobacco, and reducing caffeine and alcohol consumption. Beyond fertility window focused intercourse, identifying and managing a luteal phase deficiency will remove obstacles to conception. Diagnosing and treating polycystic ovary syndrome (PCOS) and thyroid disorders may not only hasten conception but also lead to healthier pregnancies.
Fertility awareness-based methods and fertility tracking devices are cost effective and offer patients a first step when it comes to attempting pregnancy. This approach may accelerate pregnancy without the question of whether the couple is in fact having intercourse on the appropriate days, and may alleviate the stress of even needing to consider Assistive Reproductive Technologies (ART). Although comparative research is needed to determine how fertility tracking devices stand up against untimed intercourse and other methods of fertility tracking, this research is a step in the right direction for patients to gain access to all their options, rather than just a few that become available only after a length of time.
References
[1] Bouchard TP, Fehring RJ, Schneider MM. Achieving Pregnancy Using Primary Care Interventions to Identify the Fertile Window. Front Med (Lausanne). 2018 Jan 9;4:250. doi: 10.3389/fmed.2017.00250. PMID: 29376054; PMCID: PMC5767237.
[2] Trussell J. Contraceptive failure in the United States. Contraception (2011) 83(5):397–404. 10.1016/j.contraception.2011.01.021
[3] Gnoth C, Godehardt D, Godehardt E, Frank-Herrmann P, Freundl G. Time to pregnancy: results of the German prospective study and impact on the management of infertility. Hum Reprod (2003) 18(9):1959–66. 10.1093/humrep/deg366
ABOUT THE AUTHOR
Amy Cooper, DO
Amy Cooper, DO is a resident at Western Reserve Hospital in Cuyahoga Falls where she is training in family medicine. She completed undergraduate training at Walsh University in North Canton, Ohio, where she earned a bachelor’s degree in biology with double minors in chemistry and sociology. She then completed her medical education at Ohio University Heritage College of Osteopathic Medicine in Cleveland, Ohio. She enrolled in the FACTS elective to gain insight on natural family planning methods in order to encourage her patients to feel empowered regarding their reproductive health and individual goals.
