Fats as biomarkers for
a pregnancy complication

Published November 01 2016

Chorioamnionitis, one of the most common inflammatory conditions, is associated with approximately 1 percent to 4 percent of births in the U.S. Researchers know that lipids can trigger inflammation due to injury or stress and also can help to initiate labor during pregnancy. In a recent report in the Journal of Lipid Research, researchers set out to find the composition of fats in amniotic fluid that could be linked to chorioamnionitis. Knowing the fats linked to the disease could help doctors better to diagnose and treat it.

Mothers with chorioamnionitis suffer from symptoms such as uterine tenderness, fever and rapid heart rate. Babies born prematurely to mothers with chorioamnionitis are at a higher risk for developing long-term health problems that can include cerebral palsy, growth retardation and cognitive impairment.

One complication of this condition is that 50 percent of the cases are due to microbial infection while the remaining 50 percent are not associated with infection. Unfortunately, in the cases without infection, both mother and baby are exposed unnecessarily to antibiotics, which contributes to the problem of antibiotic resistance. Krishna Rao Maddipati at Wayne State University points out that another issue, besides antibiotic resistance, is that “we don’t know what causes chorioamnionitis in the absence of infection.”

Maddipati says he and his co-workers hypothesized that “an imbalance in the composition of lipids in amniotic fluid could be a telltale sign of infection that results in chorioamnionitis.” Maddipati and co-workers also hypothesized that there could be a link between key lipid levels and chorioamnionitis in cases where there is no infection.

A paper by Maddipati and colleagues in the FASEB Journal earlier this year described how there are certain fats linked to patients with chorioamnionitis with infection. These included leukotriene B4 and 5-hydroxyicosatetraenoic acid, known as 5-HETE, which were found in higher concentrations in mothers with microbial infection. The answer to whether fat compositions are altered in cases of chorioamnionitis without infection remained elusive.

In the new JLR study, Maddipati and colleagues found a distinct profile of fats that are associated with chorioamnionitis in pregnant women without detectable microbial infection. The investigators collected samples from pregnant women without chorioamnionitis and those with chorioamnionitis both with and without microbial infection. To analyze the samples, they used mass spectrometry to determine the composition of fats within the patients’ amniotic fluid.

The researchers did not observe any significant differences in a type of lipids called prostaglandins that normally are present in amniotic fluid in mothers without chorioamnionitis compared with those with and without infection in chorioamnionitis. However, what they did discover was that epoxy fatty acids, another type of lipids found in mothers with normal pregnancies, were appreciably lower or completely absent in mothers with chorioamnionitis without infection. This is the first report to show a difference in fat profiles among patients who have chorioamnionitis without microbial infection.

This study provides insights into what causes chorioamnionitis without infection. Epoxy fatty acids play a role in reducing inflammation. The fact that they are lowered or, in some cases, absent in mothers with chorioamnionitis without infection suggests that there are insufficient fats present to keep inflammation in check. Future work to better understand what causes the reduction in these anti-inflammatory fats could help provide treatment options for patients who have chorioamnionitis without infection.

Hailey Gahlon Hailey Gahlon is a Marie Curie postdoctoral research fellow at Imperial College London. She received her master’s degree in chemistry at the University of Minnesota and her Ph.D. at ETH Zurich.