The Urgent Need to Include Pregnant and Breastfeeding Women in Medical Research
For decades, pregnant and breastfeeding women have been largely excluded from clinical trials, creating a significant gap in medical knowledge. This exclusion, historically rooted in ethical concerns, is now recognized as a barrier to providing optimal healthcare for both mothers and their children. A recent position statement from the British Pharmacological Society (BPS) is intensifying calls for change, highlighting the urgent need for greater inclusion in research.
A History of Exclusion and its Consequences
The reluctance to include pregnant and breastfeeding women in trials stems from understandable anxieties about potential harm to the fetus or infant. The thalidomide tragedy of the late 1950s, where a drug caused severe birth defects, deeply impacted the medical community and fostered a culture of caution. However, this protective approach has inadvertently led to a lack of data on the safety and efficacy of many medications used during pregnancy and lactation.
Dr. Christopher Rentsch, Associate Professor of Pharmacoepidemiology at LSHTM, notes that as many as 90% of pregnant women with a chronic condition take at least one medication, and half of breastfeeding women do too. Yet, between 2019 and 2023, pregnant women were represented in only 1.1% of clinical trials submitted to the MHRA, and breastfeeding women in just 0.6%.
The Risks of an Evidence Vacuum
This lack of evidence forces clinicians to develop decisions with incomplete information, potentially leading to undertreatment of maternal conditions or unnecessary discontinuation of vital medications. Prof. Asma Khalil, Professor of Obstetrics and Maternal Medicine at City St George’s, University of London, emphasizes that this isn’t a neutral position; it can cause anxiety for women and inconsistent advice. Poorly controlled maternal disease itself poses substantial risks to both mother and baby.
Overcoming Barriers to Inclusion
Several obstacles hinder the inclusion of pregnant and breastfeeding women in research. Trial sponsors and insurers often face high costs due to the potential for long-term harm to the baby if a safety issue arises. Dr. Victoria Male, Associate Professor in Reproductive Immunology at Imperial College London, believes a strong recommendation for inclusion, coupled with clear guidance on risk management from medicines regulators like the MHRA, is crucial. The MHRA recently consulted on this very issue, with conclusions pending.
Practical challenges also exist, including difficulties in recruiting and retaining participants due to time constraints and logistical hurdles related to breastfeeding. However, successful models demonstrate that inclusion is possible. The RECOVERY trial, a national COVID-19 treatment trial, notably included 110 pregnant women by providing explicit risk-benefit assessments to ethical and regulatory bodies and working closely with insurers.
Advances in Research Methodology
Significant advances in pre-clinical testing, modelling, and real-world evidence now offer opportunities to support the safer inclusion of these populations in drug development. The International Council for Harmonisation (ICH) has recently released guidelines to support the inclusion of pregnant and breastfeeding participants in clinical trials, requiring consideration of potential risks and benefits.
Beyond Inclusion: A Broader Focus on Women’s Health
Prof. Louise Kenny, Pro-Vice-Chancellor at the University of Liverpool, argues that the issue extends beyond pregnancy and breastfeeding. She highlights a historic underinvestment in women’s health research, leading to an incomplete understanding of how biological sex influences disease pathways and treatment responses. This disparity contributes to worse outcomes for women in many conditions.
The Role of Regulatory Bodies and Pharmaceutical Companies
Regulatory bodies should consider inclusion in principle for all relevant medicinal products. Pharmaceutical sponsors may require incentives or mandates to ensure inclusion where appropriate. Early pre-clinical testing and pharmacokinetic modelling should be mandated to support safe inclusion. The Health Research Authority is currently developing guidance on creating Inclusion and Diversity Plans to support researchers in this effort.
Frequently Asked Questions
- Why were pregnant women excluded from clinical trials in the past? Historically, concerns about potential harm to the fetus led to their exclusion, particularly after the thalidomide tragedy.
- Is it safe to take medication during pregnancy? Many medications have strong safety records, but evidence is lacking for some. Improved research will help clinicians and patients make more informed decisions.
- What is the MHRA doing to address this issue? The MHRA recently consulted on recommendations to encourage the inclusion of pregnant and breastfeeding women in clinical trials.
- What can be done to make it easier for pregnant women to participate in research? Clear guidance on risk management, strong recommendations for inclusion, and addressing financial concerns for insurers are key steps.
Pro Tip: If you are pregnant or breastfeeding and have questions about medication, always consult with your healthcare provider. Don’t rely on internet searches for medical advice.
This growing recognition of the need for inclusive research represents a pivotal shift in medical practice. By prioritizing the health and well-being of mothers and their children, we can build a more equitable and evidence-based healthcare system for all.
Did you realize? The exclusion of pregnant women from COVID-19 vaccine trials contributed to maternal mortality during the pandemic, underscoring the critical need for their inclusion in research.
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