Low birth weight can be used as a surrogate marker for adverse fetal growth in adults born at term. Those born smaller than average at term exhibited steeper corneal curvature and shorter axial length. Photo: Max Mbakop/Wikimedia Commons.

Birth weight is commonly used to predict a newborn’s likelihood of having an increased risk of postnatal complications, as it’s a reflection of the intrauterine nutrition a fetus receives during gestation. Restricted growth due to insufficient nutrition during this period has been linked to cardiovascular diseases later in life and other long-term complications arising from altered organ formation and dysfunction. A recent paper published in Acta Ophthalmologica confirmed that ocular geometry is also altered in adults born at term who were small (SGA) or large (LGA) for gestational age.

A total of 296 study participants (589 eyes; mean age 30) were examined using optical biometry. The study population included 40 severe SGA, 38 moderate SGA, 140 normal birth weight, 38 moderate LGA and 40 severe LGA individuals. Data was collected on corneal curvature, white-to-white distance, anterior chamber depth, lens thickness and axial length.

The researchers compared measurements among former moderate and severe SGA subjects with controls and former moderate and severe LGA individuals as defined in Table 1 below:

Table 1. Birth Weight Percentiles of Subjects Studied

Controls

10th to 90th

Moderate SGA

3rd to 10th

Severe SGA

1st or 2nd

Moderate LGA

90th

Severe LGA

97th

 

The researchers reported a significant association between steeper corneal curvature and moderate and severe SGA. Extreme SGA was significantly associated with smaller white-to-white distance and shorter axial length.

“Severe and moderately small for gestational age is associated with a steeper corneal curvature in subjects born at term, indicating that corneal development is also influenced by fetal malnutrition irrespective of prematurity leading to lifelong alterations in ocular geometry,” the researchers concluded in their paper. They added that their study “provides new data about the effects of restricted and excessive growth on ocular geometric long-term outcomes in adults [now aged 18 to 52] born at term.”

Fieß A, Schultheis A, Mildenberger E, et al. Ocular geometry in adults born small, appropriate or large for gestational age at term. Acta Ophthalmol. April 18, 2023. [Epub ahead of print].