Laura Hernandez awarded NIH grant to study impacts of antidepressants and breastfeeding on bone health

Laura Hernandez, associate professor of dairy science, is part of a team recently awarded an R01 grant from the National Institutes of Health. Also on the grant are UW–Madison School of Veterinary Medicine’s Chad Vezina and Rob Lipinski, and Harvard University’s Julia Charles. The five-year grant will provide the researchers with over $1.5 million to study how a type of antidepressants may affect bone health in breastfeeding mothers.

Interest in the impact of selective serotonin reuptake inhibitors (SSRIs) on bone density grew out of Hernandez’s work looking at milk fever, a disease caused by low levels of circulating calcium in cows. She found that higher levels of circulating serotonin led to higher levels of calcium in the blood for some breeds. That was a good thing for cows with milk fever but raised concerns about women taking SSRIs to treat depression.

SSRIs are known to increase serotonin activity in the blood, which, if Hernandez’s findings apply to people, means that taking SSRIs could lead to an increase in calcium levels in the blood. More calcium in the blood means less in the bones. In fact, people who take SSRIs show signs of increased fracture risks and osteoporosis. Breastfeeding can exacerbate the issue since women who exclusively breastfeed for six months can lose up to 10 percent of their bone mass. A new mother taking SSRIs could be particularly vulnerable to bone loss.

“We are trying understand the physiology by which using SSRIs during pregnancy and lactation decreases maternal bone health later in life,” says Hernandez. “We’re hoping to fully understand how taking a medication like an SSRI can have long-term impacts on mom.”

Hernandez and her team will use mice to figure out how breast and bone tissue are communicating, how that communication is affected by serotonin signaling and SSRIs during lactation, and how bone mass could be conserved. Preliminary data suggests that folic acid may be a way to provide protection.

“We need to focus on helping new moms,” says Hernandez. “We want to determine if we can offer a preventative measure during pregnancy and lactation that allows mothers to stay on their medication and breastfeed – a way to protect their bone health and mental health simultaneously.”