Photo: Amina Filkins


A recent doctoral thesis by Noora Houttu from the University of Turku reveals that overweight and, specifically, obesity during pregnancy cause changes in the mother's physiology and increase the risk of pregnancy complications such as gestational diabetes.

During a normal pregnancy, there are changes in the mother's immune response and metabolism that support fetal growth and development.

The findings of Noora Houttu's dissertation research indicate that obesity during pregnancy amplifies these changes, which can have detrimental effects on the mother's health. In the early stages of pregnancy, obese mothers had elevated levels of low-grade inflammation and markers of lipid metabolism compared to overweight mothers. The gut microbiota was also altered in obese individuals compared to those who were overweight.

The study involved measuring highly sensitive C-reactive protein (CRP) and a newer marker of low-grade inflammation, glycoprotein acetylation. Additionally, the researchers determined the metabolic profile from blood samples and analyzed the gut microbiota from fecal samples in early pregnancy.

"By identifying risk markers for health problems in early stages, we can potentially target interventions to those individuals who are at higher risk of developing complications," Houttu suggests.

Changes in Blood Biomarkers in Early Pregnancy Associated with the Onset of Gestational Diabetes in Late Pregnancy

The research also examined markers of low-grade inflammation, metabolism, and vaginal microbiota in healthy mothers who developed gestational diabetes in late pregnancy. The study revealed that the marker of low-grade inflammation in early pregnancy was not associated with the onset of gestational diabetes, but low concentrations of phIGFBP-1 and IGFBP-1 marker proteins were. This is intriguing from the perspective of gestational diabetes, as these markers are associated with insulin metabolism. Furthermore, specific types of bacteria were found in the vagina of women who developed gestational diabetes.

"The study demonstrates that a series of changes in metabolism and microbiota precede the onset of gestational diabetes, providing potential new targets for developing risk indicators," Houttu reflects.

Additionally, the study found that n-3 polyunsaturated fatty acids, commonly known as omega-3 fatty acids, were associated with an increased risk of developing gestational diabetes. Omega-3 fatty acids are generally considered beneficial for health. The unexpected result calls for further investigation.

Houttu also examined the relationships between low-grade inflammation, metabolism, and vaginal microbiota in early pregnancy. The study showed that markers of low-grade inflammation were associated with markers of fatty acid and amino acid metabolism. Low-grade inflammation may potentially cause changes in metabolism, which can be detrimental to health.

Furthermore, the study determined markers related to metabolism and inflammation in vaginal samples. Interestingly, the marker of low-grade inflammation in blood was not associated with the composition of vaginal microbiota, but the enzyme MMP-8 was linked to a lower abundance of two beneficial bacteria in the vaginal microbiota.

"Previous studies have shown that a reduction in these bacteria and an imbalance in microbiota can increase the risk of pregnancy complications. MMP-8 could potentially serve as an indicator of balance in the vaginal microbiota," Houttu speculates.

Fish Oil and/or Probiotics as a Possible Solution for Restoring Imbalanced Vaginal Microbiota

Houttu's doctoral research is part of a larger mother-child study aiming to investigate the effects of fish oil and probiotics on maternal and child health.

The results indicate that fish oil and/or probiotics may reduce potentially harmful bacteria in the vagina. This finding is unique as the interaction of fish oil, and the combination of fish oil and probiotics, with the vaginal microbiota has not been previously studied in pregnant women. Some preliminary research exists on the effects of probiotics.

"N-3 polyunsaturated fatty acids are essential for the development of the fetal central nervous system. If maternal fish intake is not in line with recommendations, fish oil supplementation could be a means to increase blood concentrations and ensure sufficient supply to the fetus," Houttu contemplates.

In conclusion, Noora Houttu's research sheds light on the impact of obesity during pregnancy on various aspects of maternal health, including low-grade inflammation, metabolism, and gut and vaginal microbiota. The findings highlight the importance of early detection and intervention to mitigate the risks associated with maternal obesity and improve outcomes for both mothers and their babies. Further studies are needed to explore potential strategies, such as fish oil and probiotics, for restoring balance in the vaginal microbiota and promoting overall maternal well-being.