Efficiency of afamin and fibroblast growth factor 21 for early prediction of gestational diabetes mellitus

Why early clues in pregnancy matter

Many women develop high blood sugar for the first time while pregnant, a condition called gestational diabetes. It can raise the chances of early delivery, heavier babies, and birth by cesarean section. Today, doctors usually find it only halfway through pregnancy, when some of the damage may already be done. This study asked whether simple blood tests in the first trimester could flag women at risk much earlier, using two lesser known proteins in the blood.

Looking for warning signs in the blood

The researchers followed 43 pregnant women in Egypt. Seventeen had no known problems, while 26 had at least one risk factor for gestational diabetes, such as obesity, older age, or a history of the condition. All women gave fasting blood samples twice, once in early pregnancy between 8 and 12 weeks and again between 22 and 28 weeks. The team measured usual diabetes markers like fasting glucose, insulin, and long term blood sugar, along with liver and kidney function. They also measured two proteins called afamin and fibroblast growth factor 21, which are involved in how the body handles fats, sugars, and oxidative stress.

How the two markers behaved during pregnancy

Women who later developed gestational diabetes already looked different in the first trimester. They were older, had higher body mass index, and higher blood pressure. Their standard diabetes measures were also raised, showing early insulin resistance. At this same early time point, levels of afamin in their blood were much higher than in women with normal pregnancies. By the second trimester, afamin levels in the two groups looked similar, and in the diabetes group afamin had actually fallen compared with their own earlier levels. In contrast, the second marker, fibroblast growth factor 21, was higher in the diabetes group at both time points and did not change much over time.

Links to baby outcomes and organ health

The study also explored how these markers related to the health of the mothers and their babies. In women who developed gestational diabetes, higher afamin in early pregnancy went hand in hand with higher body mass index, higher blood sugar, higher insulin, and heavier newborns. This pattern did not appear in women with normal pregnancies. Standard tests showed that women with gestational diabetes had slightly higher signs of liver strain and reduced kidney function even early on, although most values stayed within usual medical limits. Fibroblast growth factor 21, despite being consistently higher in the diabetes group, did not show clear links with these other measurements or with birth weight.

How well the markers predicted later diabetes

To judge how useful these proteins might be in real world screening, the researchers used statistical tools that compare how well a test separates people who will get a condition from those who will not. In the first trimester, afamin alone correctly distinguished future gestational diabetes cases most of the time. Fibroblast growth factor 21 did slightly better. When the two markers were combined in one calculation, their performance improved further, with high sensitivity and reasonable specificity for identifying women who would later develop gestational diabetes. By the second trimester, when standard sugar tests are usually done, afamin by itself no longer added much information, while fibroblast growth factor 21 and the combined measure still showed some predictive value but not as strong as early in pregnancy.

What this could mean for pregnant women

The authors conclude that measuring afamin and fibroblast growth factor 21 in the first trimester may help identify women at higher risk for gestational diabetes before blood sugar levels clearly cross the diagnostic line. The work involved a relatively small number of women at a single hospital, so the findings need to be checked in larger and more diverse groups. Still, the results suggest that a simple early pregnancy blood test, added to routine care, might one day support closer follow up and earlier lifestyle or medical steps for women who need them most, helping to protect both mother and baby.

Citation: Sabri, A.O., Elhady, M.M., Hemida, E.H. et al. Efficiency of afamin and fibroblast growth factor 21 for early prediction of gestational diabetes mellitus. Sci Rep 16, 14716 (2026). https://doi.org/10.1038/s41598-026-51453-7

Keywords: gestational diabetes, pregnancy, biomarkers, afamin, FGF21