Physical Activity During Fertility Treatment: Evidence, Mechanisms, and Clinical Implications

Abstract

Physical activity is increasingly recognized for its potential influence on reproductive outcomes, particularly during fertility treatments such as in vitro fertilization (IVF) and ovulation induction. Despite longstanding concerns regarding exercise-induced reproductive dysfunction, contemporary evidence suggests that moderate and individualized physical activity may offer clinical benefits without compromising treatment success. This review synthesizes current research, elucidates underlying mechanisms, and provides practical recommendations for integrating physical activity into fertility care, with an emphasis on clinical safety, patient selection, and guideline-based management.

Introduction

Infertility affects a significant proportion of reproductive-age couples globally, with assisted reproductive technologies (ART) playing a pivotal role in management. Lifestyle factors, including physical activity, are increasingly appreciated as modifiable contributors to reproductive health and treatment outcomes. The interplay between exercise, endocrine function, and fertility is complex, necessitating evidence-based guidance for clinicians managing patients undergoing fertility treatments. This article reviews the role of physical activity during fertility treatment, focusing on epidemiology, mechanisms, risks, and clinical strategies tailored to optimize reproductive success.

Epidemiology / Disease Burden

Infertility impacts approximately 10-15% of couples worldwide, with rising utilization of ART and fertility interventions. Sedentary lifestyles and obesity are prevalent among infertility patients, contributing to anovulation, polycystic ovary syndrome (PCOS), and impaired ART outcomes. Population-level studies reveal that physical inactivity is a modifiable risk factor for subfertility and adverse pregnancy outcomes. Conversely, the prevalence of excessive or inappropriate exercise, particularly among elite athletes, remains low but poses unique clinical challenges due to exercise-induced hypothalamic dysfunction.

Pathophysiology

The relationship between physical activity and reproductive function is mediated by neuroendocrine, metabolic, and inflammatory pathways. Moderate exercise enhances insulin sensitivity, modulates hypothalamic-pituitary-gonadal (HPG) axis function, and reduces systemic inflammation, all of which are beneficial for ovulatory function and endometrial receptivity. However, excessive or high-intensity exercise may disrupt gonadotropin-releasing hormone (GnRH) pulsatility, leading to menstrual disturbances, luteal phase defects, and impaired implantation. The type, intensity, and duration of activity, as well as baseline nutritional status, are critical determinants of the net reproductive effect.

Risk Factors

Risk factors for adverse reproductive effects of physical activity include high-intensity endurance training, low body mass index (BMI), negative energy balance, and underlying eating disorders. In the context of fertility treatment, patients with PCOS, obesity, or insulin resistance may particularly benefit from tailored physical activity interventions. Conversely, women with hypothalamic amenorrhea or low reserve should avoid excessive exercise. Clinical assessment of physical activity patterns, nutritional status, and psychological stress is essential in risk stratification and management planning.

Clinical Features

Clinically, excessive exercise may manifest as menstrual irregularity, amenorrhea, or luteal insufficiency, often coexisting with low BMI and reduced bone mineral density. During ART cycles, there are concerns regarding exercise-induced ovarian torsion, altered ovarian blood flow, or impaired endometrial receptivity, though such complications are rare with moderate activity. Conversely, sedentary patients may present with obesity, metabolic syndrome, and increased risk of treatment failure or pregnancy complications.

Diagnosis

Assessment of physical activity in infertility patients should include detailed history-taking regarding exercise frequency, intensity, duration, and type, as well as evaluation of dietary intake and psychosocial factors. Objective measures, such as validated physical activity questionnaires or wearable activity monitors, may supplement clinical judgment. Laboratory assessment of reproductive hormones, metabolic parameters, and bone health, as indicated, supports a comprehensive evaluation.

Treatment & Management

Management strategies should be individualized, balancing the benefits of moderate physical activity against potential risks of over-exertion. For most patients, moderate-intensity aerobic activity (e.g., brisk walking, cycling) totaling 150 minutes per week is considered safe and beneficial during fertility treatment. Resistance training may be added for metabolic health, particularly in patients with PCOS or obesity. Patients should be counseled to avoid high-impact activities or those with elevated risk of abdominal trauma during ovarian stimulation. Multidisciplinary collaboration with dietitians and psychologists is recommended for those with disordered eating or high-risk exercise behaviors.

Recent Advances / Emerging Therapies

Recent studies demonstrate that structured physical activity interventions can improve ovulation rates, ART outcomes, and live birth rates, particularly in overweight or obese women. Emerging evidence supports the use of digital health tools, such as mobile activity trackers and telehealth coaching, to enhance adherence and monitor patient safety. Research into the molecular effects of exercise on endometrial receptivity, oocyte quality, and embryo implantation is ongoing, with promising implications for precision fertility care.

Guideline Recommendations

Leading reproductive and obstetric societies, including the American Society for Reproductive Medicine (ASRM) and the European Society of Human Reproduction and Embryology (ESHRE), endorse moderate physical activity for most women undergoing fertility treatment. Guidelines recommend individualized counseling, avoidance of strenuous or high-risk activities during ovarian stimulation, and interdisciplinary management for complex cases. Patient education should emphasize safe exercise practices, nutritional adequacy, and recognition of menstrual or metabolic disturbances.

Conclusion

Physical activity during fertility treatment confers significant metabolic and reproductive benefits when tailored to individual patient profiles. While excessive exercise poses identifiable risks, moderate activity is generally safe and may improve treatment outcomes, particularly in women with metabolic dysregulation. Clinicians should incorporate evidence-based physical activity counseling and risk assessment into routine fertility care, optimizing reproductive and overall health.