Breaking Barriers: New Research Shows Higher BMI Patients Can Safely Access IVF

A larger-bodied person with dark brown eyes adn long, wavy, dark hair, wears brick red lipstick and a beige tank. She flexes her arm, and looks to the side.

When Sarah* walked into her fertility clinic, she carried more than hope for a family. She also carried the weight of years spent navigating a healthcare system that seemed to close doors based on numbers on a scale. Like many people seeking fertility treatment, Sarah faced Body Mass Index (BMI) restrictions that effectively barred her from accessing in vitro fertilization (IVF), despite having no other medical contraindications.

(*Sarah represents a composite of experiences shared by many patients, not a specific individual from the study.)

This scenario plays out daily across fertility clinics nationwide, where BMI cutoffs create barriers to reproductive care for larger-bodied individuals. However, groundbreaking new research published in Fertility and Sterility is challenging these restrictive practices and offering hope for thousands of people who have been denied treatment based solely on their body size.

The Research That's Inviting a Change In the Conversation

A comprehensive study led by Dr. Marissa Luck and colleagues at Oregon Health & Science University examined 98 patients with BMIs of 40 kg/m² and above who underwent egg retrieval between 2018 and 2023. The research directly compared outcomes between those with BMIs of 40-44.9 kg/m² and those with BMIs of 45 kg/m² and higher—a group often excluded entirely from fertility care.

The results were striking: patients with BMIs of 45 kg/m² and above experienced virtually identical safety profiles and treatment outcomes compared to those in the lower BMI category. Most significantly, 93% of all participants experienced no anesthesia complications whatsoever. The only adverse event reported was temporary oxygen desaturation below 90% in just 7% of cases—a manageable situation that required no advanced interventions.

"When using intravenous sedation, patients with a BMI of ≥45 kg/m² have similar ART outcomes with few anesthesia or ART complications compared with those with a BMI of 40–44.9 kg/m²," the researchers concluded. This finding directly contradicts the assumption that higher BMI automatically equals higher risk.

The Hidden Cost of BMI Discrimination

The implications of this research extend far beyond the realm of medical statistics. Currently, 62% of fertility clinics report using BMI thresholds to exclude patients from treatment, with many setting arbitrary cutoffs that lack scientific justification. This practice disproportionately affects people who may already face multiple barriers to building families.

For people assigned female at birth, time is often a critical factor in fertility success. Age-related fertility decline means that delays caused by weight-loss requirements can significantly impact treatment outcomes. When clinics mandate weight loss before treatment, they're essentially asking people to gamble with their reproductive timeline, often for requirements that this new research suggests may not be medically necessary.

The psychological toll is equally concerning. The Association for Size Diversity and Health (ASDAH) has long advocated for healthcare approaches that prioritize health-promoting behaviors over weight loss, recognizing that weight stigma itself can harm both physical and mental health. When fertility clinics require weight loss, they risk triggering disordered eating behaviors, extreme dieting practices, and psychological distress that can actually worsen health outcomes.

Additionally, BMI as a measure for body mass is inherently flawed despite its widespread adoption as a metric for health status. Its calculation was based on 17th-century white males and doesn’t accurately assess overall body composition. It also doesn’t account for sex, age, or ethnicity. Clearly, a better, affordable body mass measurement is needed, but that is for another post.

A More Nuanced Approach to Risk Assessment

The study's authors emphasize that their findings don't suggest abandoning medical evaluation entirely. Instead, they advocate for individualized risk assessment rather than blanket BMI restrictions. Their protocol included comprehensive pre-treatment evaluation by reproductive endocrinologists, anesthesia providers, and other specialists to ensure each patient was optimally prepared for treatment.

"Rigorous prescreening and counseling for all patients with a BMI of ≥40 kg/m² are essential for patient safety and success," the researchers noted. This approach focuses on addressing specific medical conditions and optimizing overall health rather than fixating solely on weight reduction.

The study also revealed practical considerations that clinics can easily accommodate. While patients with higher BMIs required slightly longer procedure times (an average of 4.3 additional minutes) and higher medication doses, these differences posed no safety concerns and required no specialized equipment or training.

Study Limitations and Future Directions

It's important to acknowledge this research's limitations. The study included a relatively small sample size over five years, and some patients with BMIs over 50 kg/m² were still excluded due to institutional policies. Additionally, the research focused specifically on egg retrieval procedures using conscious sedation rather than general anesthesia, and pregnancy outcomes, while encouraging, showed trends toward higher miscarriage rates in the higher BMI group that warrant further investigation.

The researchers also noted that their findings apply specifically to carefully screened patients who underwent thorough pre-treatment evaluation. This doesn't eliminate the need for appropriate medical assessment; rather, it suggests that assessment should focus on individual health factors rather than BMI alone.

Moving Toward Inclusive Fertility Care

This research adds to a growing body of evidence suggesting that many BMI-based restrictions in healthcare lack scientific justification and may cause more harm than benefit. For fertility care specifically, where timing can be crucial and where people are already navigating significant emotional and financial stress, these barriers can be particularly devastating.

The path forward requires healthcare providers to reconsider policies that may inadvertently discriminate against individuals who are larger-bodied. Rather than blanket BMI restrictions, clinics can adopt comprehensive health assessments that evaluate each person's individual circumstances, medical history, and risk factors.

For people currently facing BMI-based treatment denials, this research provides valuable ammunition for advocating with healthcare providers. It also highlights the importance of seeking care from providers who prioritize evidence-based, individualized treatment approaches over arbitrary restrictions.

The Bigger Picture

The conversation about BMI restrictions in fertility care reflects broader issues of weight bias in healthcare.When medical decisions are based on body size rather than individual health status, we risk perpetuating discrimination that can delay or deny essential care to those who need it most.

As this research demonstrates, with appropriate screening and preparation, people across a wide range of BMIs can safely access fertility treatment with excellent outcomes. The question isn't whether larger-bodied people should receive fertility care—it's how healthcare systems can best support all individuals in their journey toward building families.

Moving forward, the fertility field has an opportunity to lead by example, showing how evidence-based medicine can replace outdated assumptions and create more inclusive, effective care for all patients seeking to grow their families.

Unbiased support of people of all sizes trying to conceive is a core mission at Rosefinch Health. Dr. Lee Hullender Rubin, DAoM, MS, LAc, FABORM, moves through the world in a fat body and centers size diversity in her Portland, Oregon, clinical practice. Whether you are smaller bodied, small fat or infini-fat or somewhere in between, we welcome you. Have questions about accessibility? Email us to learn more.

Photo by Alyssa Baches on Unsplash