A new, non-invasive test could be used in early pregnancy to predict preterm birth and poor fetal development.
Growth failure, accelerated weight gain, cardiovascular disorders and other health problems in childhood are associated with preterm birth and fetal growth restriction.
Preterm birth is defined as being when a baby is born before the 37th week of pregnancy. Fetal growth restriction is when a newborn’s birth weight falls below the 10th percentile of their predicted birth weight.
Preterm birth is becoming more common – over the past 10 years it has increased by 19.4% in developed regions, with the US accounting for 42% of all preterm births in 2010.
A recent report also found that Greece has seen a sharp increase in preterm birth over the past 20 years. The new study, therefore, examined a cohort of mothers and children from Crete in an attempt to find molecular biomarkers that may form the basis of a screening test to predict preterm birth or fetal growth restriction.
The new study builds on previous research along these lines, and is the largest study in humans so far to examine urinary metabolomics for predicting risk of preterm birth and fetal growth restriction.
The researchers wondered if abnormalities in lipid storage and some metabolic pathways in the first trimester could predict fetal growth impairment. This is because extensive changes of these factors are necessary in the first trimester to facilitate the development of the fetus.
The team analyzed the metabolites found in the urine of 438 pregnant women, and detected that elevated levels of the amino acid lysine were associated with spontaneous preterm birth. They also discovered that increased levels of an N-acetylated glycoprotein were found in women who had to be induced early.
Metabolic biomarkers were also identified for poor fetal development. Decreased levels of the molecules acetate, formate, tyrosine and trimethylamine, were associated with fetal growth restriction. What is more, women with decreased levels of these metabolites were found to be at higher risk of diabetes, as they may have higher blood insulin.
Hector Keun, lead researcher from the Department of Surgery and Cancer at Imperial College London in the UK, describes the findings:
“While we know that metabolism in the mother changes substantially during pregnancy to help supply the growing fetus with nutrients, we were surprised to see so early in pregnancy a link between metabolites that we could easily detect in a urine sample and low birthweight.
Our findings imply that it could be possible to improve the identification of women at higher risk of delivering smaller babies or premature delivery using non-invasive metabolic profiling technology early in pregnancy.”
Keun says that further investigation of the factors that produce the molecules associated with preterm birth and poor fetal development will help to reduce the likelihood of these harmful pregnancy outcomes.
“We will also go on to test if exposure to these metabolites during pregnancy has a lasting impact on child development after birth,” he adds. The team will repeat the study in several more countries to understand the causal factors behind the observations.
As for why preterm birth has become so much more common in first world countries such as Greece and the US, Keun told Medical News Today that the answer is not yet clear, “but the rate of the rise suggests an environmental and not genetic cause, and it is these environmental factors that we are actively researching.”
Recently, Medical News Today reported on a UK-based study that found preterm newborns are 30-50% more likely to survive in busy neonatal centers, compared with less busy centers.