Qualitative Study Finds Supervised Prolonged Fasting Acceptable for Infertility Patients

In an exploratory qualitative investigation nested within a randomized controlled trial, researchers evaluated how women navigating infertility experienced a medically supervised, prolonged fluid-only fasting intervention. Infertility impacts roughly 17.5 percent of couples worldwide, defined formally as the inability to conceive after twelve months of unprotected intercourse. While conventional assisted reproductive technologies such as in vitro fertilization provide clinical pathways toward pregnancy, their overall delivery is constrained by limited success rates—in Germany, for example, only 15 to 22 percent of treatment cycles culminate in a live birth. Moreover, assisted reproductive technologies place a disproportionate physical and emotional demand on female partners, who frequently encounter complications including ovarian hyperstimulation syndrome, heightened anxiety, depressive symptoms, and significant economic costs. Discontinuation rates compound across successive cycles, climbing from 26.5 percent after the initial round to 47.9 percent after five rounds, with psychological distress commonly cited as a primary driver. Against this backdrop of medical strain and social normativity surrounding family formation, many individuals actively explore complementary lifestyle strategies. The present qualitative study examined the feasibility, subjective acceptability, and perceived psychosocial impacts of seven-to-ten-day medically supervised fasting among women seeking reproductive care.

The biological rationale for investigating dietary restriction in reproductive medicine centers on the intricate connections between systemic metabolism, endocrine signaling, and chronic immune activation. Aside from clear anatomical impediments, difficulties in conceiving often involve disruptions in metabolic, inflammatory, and hormonal pathways. In particular, chronic low-grade systemic inflammation has been identified as a contributing factor in compromised ovarian performance and related fertility processes. Prolonged and intermittent fasting regimens have previously shown anti-inflammatory properties across clinical and laboratory settings, exerting measurable influences on oxidative stress markers and insulin sensitivity. Emerging investigations, especially those involving cohorts diagnosed with polycystic ovary syndrome, have observed that intermittent fasting protocols can contribute to improved hormonal balance and metabolic profiles. Furthermore, clinical fasting literature has recorded subsequent improvements in general mood and subjective quality of life among diverse patient populations, suggesting that an outpatient fasting program might alleviate some of the profound psychological and physical strains frequently experienced during prolonged fertility struggles.

To investigate these dynamics directly, the research team embedded an interview-based study within an outpatient randomized controlled trial registered under ClinicalTrials.gov identifier NCT04942457, which had obtained formal ethical approval from the ethics committee of Charité-Universitätsmedizin Berlin in January 2018 under protocol ID EA4/216/17. The clinical intervention required participants to follow a prolonged fluid-only fasting protocol lasting an initial minimum duration of seven days, with the personal option to extend the fast up to ten days based on mutual agreement between the participant, study physician, and research dietitians. During this intensive fasting interval, daily caloric intake was constrained to a maximum of 300 kilocalories, consumed exclusively as strained vegetable broths and diluted juices. Participants were instructed to maintain an overall daily fluid consumption of two to three liters using plain water and unsweetened herbal teas. Professional clinical oversight was systematically integrated into the intervention design, featuring pre-fasting consultation and at least two structured telephone contacts with a certified dietitian during the fasting period to monitor protocol compliance, address acute discomforts, and tailor behavioral guidance.

Recruitment for the parent clinical trial was conducted between December 2021 and December 2022 across three specialized fertility centers located in Berlin, Germany, with supplemental outreach extended to social media platforms such as Instagram and reproductive health portals following initial enrollment bottlenecks. The study criteria specified women aged 25 to 45 years with a body mass index between 20 and 40 kilograms per square meter who were experiencing infertility. In total, 18 women were randomized to the fasting arm of the trial, 13 of whom formally initiated the caloric restriction protocol. While the qualitative research protocol originally aimed for maximum variation sampling and theoretical saturation, recruitment constraints and the early termination of the parent trial necessitated a pragmatic sampling approach. Ultimately, eight women consented to and completed in-depth, semi-structured qualitative interviews. These interviews were conducted in German via the secure Samedi teleconsultation platform between February 2022 and January 2023, scheduled within five weeks of completing the fasting regimen to preserve clear experiential recall.

The resulting qualitative sample comprised eight women aged 30 to 44 years who possessed a generally high level of formal education, with seven holding university degrees and one having completed formal vocational training. Most were employed either full-time or part-time, while two participants already had children. Their prior engagements with assisted reproductive technologies were varied: several had previously undergone multiple unsuccessful treatment cycles and decided to forgo further medical interventions, others had actively chosen against assisted reproduction from the outset, and another subset remained uncertain about pursuing future cycles. For six of the eight women, the intervention represented their very first experience with prolonged fasting. Demonstrating substantial adherence to the intensive clinical regimen, seven of the eight participants successfully completed the mandatory seven-day protocol. Only one participant elected to terminate the fast prematurely after six days, citing the necessity of participating in an important business meeting where she felt reduced cognitive focus might impair her professional performance.

Audio recordings of the interviews, which averaged 53 minutes in duration and ranged from 37 to 68 minutes, were transcribed verbatim and analyzed using inductive thematic analysis facilitated by MAXQDA 2022 software following established qualitative methodologies. Transcripts were subjected to systematic open coding, category synthesis, and iterative peer review within an interdisciplinary research colloquium to support interpretive rigor. The primary analytical finding was that medically supervised prolonged fluid-only fasting proved acceptable to the interviewed cohort. Participants universally reported experiencing notable positive mental and somatic shifts during the caloric restriction period. These included enhanced mental alertness, feelings of somatic lightness, increased calmness, emotional grounding, and a mindful appreciation of basic nutritional intake. Multiple participants described an intentional deceleration of daily routines, which allowed them to incorporate restorative moments of physical activity, self-care, and quiet reflection that had previously been sidelined by busy work schedules and conventional meal preparation.

Nevertheless, adherence to the fasting protocol did not imply an absence of physical and emotional hurdles. All eight participants documented encountering distinct difficulties that varied in intensity throughout the intervention. Universal among the reported complaints was physical fatigue, particularly during the initial transitional days. Participants also noted consistent dissatisfaction with the sensory properties of the fasting meals, describing the permitted broths and juices as monotonous, unpalatable, or bland. Beyond these predictable physical discomforts, participants identified emotional fluctuations, transient depressive feelings, and sharp food cravings as more challenging to navigate. Cravings occurred far more frequently than biological hunger and proved particularly acute in communal spaces where other individuals were consuming solid food. In response, some participants deliberately engaged in social withdrawal to avoid food-centered gatherings, which occasionally introduced an acute sense of isolation and temporary reduction in interpersonal wellbeing.

To navigate these compounding strains, participants relied heavily on a combination of internal motivation, personal coping adaptations, and formal clinical support structures. The primary driver sustaining initial enrollment and persistence was a deeply held desire to improve personal reproductive prospects, optimize general metabolic health, or achieve weight reduction. As the intervention progressed, participants increasingly described an externalized sense of accountability toward the scientific study itself, noting that knowing investigators relied on their data provided a powerful barrier against premature dropout. Structured telephone interactions with the study dietitian served a crucial sustaining function, offering tailored reassurance, troubleshooting physical complaints such as dizziness, and providing an objective mechanism of accountability. On an individual level, participants altered their daily workflows, integrated calming activities such as walking in nature or extra sleep, and modified allowed broths to make the sensory experience more tolerable.

A critical qualitative observation was the transformative influence that fasting exerted over participants’ attitudes toward their reproductive journeys. Infertility frequently induces feelings of profound disempowerment, bodily failure, and psychological helplessness due to the passive reliance on invasive clinical treatments. Engaging in prolonged fasting offered many participants a tangible opportunity to reclaim personal agency, transforming their stance from passive medical recipients into active agents in their own health care. Interestingly, the psychological outcomes diverged: while some women concluded the fast with renewed hope and enthusiasm for future assisted reproduction, others arrived at an enhanced state of emotional acceptance regarding the possibility of remaining childless. Successfully enduring a demanding seven-day fast strengthened participants’ perceived self-efficacy, allowing them to reconsider rigid biographical expectations surrounding compulsory motherhood and fostering a more forgiving, caring relationship with their physical bodies.

The authors acknowledged several key methodological limitations that contextualize these findings. Because recruitment was constrained by the early closure of the larger randomized trial, the small cohort of eight predominantly middle-class, highly educated German women prevents assumptions of theoretical saturation, limiting the transferability of the conclusions to broader socioeconomic, cultural, or occupational groups. Individuals engaged in strenuous manual labor, for instance, might encounter distinct somatic barriers that did not emerge in this largely sedentary professional cohort. Additionally, only one participant in the interviewed group had discontinued the protocol early, meaning that the perspectives of individuals who find prolonged fasting intolerable remain underrepresented. The investigators also highlighted that the clinical background of senior researchers in integrative and fasting medicine represented both an asset for contextual interpretation and a potential source of confirmation bias, although investigator triangulation and reflexive discussions were employed to balance analysis. Quantitative analyses will ultimately be required to verify whether these subjective perceptions of renewed health translate into verifiable clinical improvements in fertility outcomes.

Subject of Research: Qualitative evaluation of patient experiences during a medically supervised prolonged fasting intervention for infertility

Article Title: Women’s experiences of a medically supervised fasting intervention for infertility: a qualitative study

Article References: Behling, J. N., May, K. T., Batschari, K., Sochiera-Plegniere, K., Blakeslee, S. B., Stritter, W., Jeitler, M., Kandil, F. I., Kunz, B., Prüß, A., Michalsen, A., & Koppold, D. A. (2026). Women’s experiences of a medically supervised fasting intervention for infertility: a qualitative study. BMC Women's Health, 26(1), Article 511. https://doi.org/10.1186/s12905-026-04978-y

Image Credits: AI Generated

DOI: 10.1186/s12905-026-04978-y

Keywords: infertility, prolonged fasting, qualitative research, reproductive health, assisted reproductive technology, thematic analysis, dietary intervention, patient experience, clinical trial, psychological wellbeing, fasting protocol, integrative medicine, maternal health, coping strategies, dietitian support, lifestyle intervention