PharmSci student’s research advances medication safety during pregnancy

As an undergraduate student at the University of Toronto, Diana Nelles learned about Frances Kelsey, a Canadian woman who worked for the United States Food and Drug Administration (FDA) in the 1960s as a pharmacologist. Kelsey was responsible for the FDA’s refusal to approve thalidomide for the treatment of nausea in pregnancy – a decision that prevented many babies from being born with birth defects caused by the drug.

Kelsey’s story inspired Nelles to pursue a career in pharmacology and to conduct research that informs better decision-making about medication usage in pregnancy.

“I was really inspired by this woman who followed the evidence and listened to her intuition, knowing that her decisions carried significant implications for many people. She was kind of a role model for entering this field, and her story had a big impact on me,” says Nelles. “Her story shows that research into drug safety in pregnancy makes such a difference in people’s lives.”

Nelles completed her Bachelor of Science with specialties in pharmacology and toxicology and then completed a master’s degree in neuroscience at McGill University. In 2024, she returned to Toronto to start a PhD in pharmaceutical sciences with Professor Micheline Piquette-Miller focusing on drug safety in pregnancy.

“Drug safety is always important, especially in special patient populations like pregnant people, where research is limited. I wanted to study in a lab that focused on bridging these existing gaps,” says Nelles. “One of the things that drew me to Dr. Piquette-Miller’s lab was the emphasis on translational research and the collaborations with local hospitals, and I thought that was really exciting.”

Piquette-Miller’s research focuses on drug transporter proteins in the placenta that regulate the movement of drugs, nutrients, and other molecules between the mother and fetus.

For Nelles’ PhD project, she is studying drug transporter proteins in the placenta of pregnant people with the autoimmune disease lupus. She is examining whether inflammation experienced by people with lupus alters the amount or activity of drug transporters in the placenta. Her findings will help to assess the impact of drug exposure to the fetus, which may have implications for medication use during pregnancy.

People with lupus need to continue taking their medication throughout pregnancy, but there is very little information about how these medications can affect the fetus. Nelles’ research aims to address this knowledge gap and ultimately help with guiding the prescribing of medication for lupus during pregnancy.

“The risk of fetal drug exposure is a significant point of concern, as these drug transporters protect the fetus by preventing drugs from crossing the placenta. If their numbers or activity change because of lupus-mediated inflammation, that could impact the exposure to some of the common medications that are taken,” says Nelles.

“Down the road, I hope that this research helps to improve prescribing guidelines for women with lupus and contributes to the ongoing research worldwide that aims to optimize therapies during pregnancy. Prioritizing the mother’s health and minimizing any risks to the fetus is absolutely critical in these patients.”

Women and girls remain underrepresented in science education and careers

Complementing her research in the Piquette-Miller lab, in 2024–2025 Nelles participated in the Canadian Mother-Child Collaborative Training Platform, a one-year certificate program that provides interdisciplinary training in perinatal research. She was able to participate in seminars, workshops and conferences to learn from a broad range of perinatal researchers, including leaders in toxicology, pharmacogenomics and machine learning, which she says was a valuable learning and networking opportunity.

“Pregnancy research is a niche topic, and this program brings together specialists from across Canada whose insights provide diverse perspectives in such a specialized field,” says Nelles. “Even though the specific discipline of each student within each cohort may be different, it's nice to learn alongside each other and have support in a field that isn’t as prominent as other fields of research.”

“Encouraging girls and women to pursue scientific careers will strengthen and advance science, as they bring their own perspectives shaped by own experiences, especially in the field of maternal fetal health.”

Women, especially pregnant women, are underrepresented in health research and clinical trials. And, according to the United Nations, women make up only 35 per cent of science graduates and 31 per cent of scientific researchers globally.

As a woman working in science and studying pregnancy, Nelles is contributing valuable perspectives to an understudied scientific field.

“Encouraging girls and women to pursue scientific careers will strengthen and advance science, as they bring their own perspectives shaped by own experiences, especially in the field of maternal fetal health,” says Nelles. “Our insights will contribute to a more complete understanding of many scientific topics.”