Altered umbilical sex steroids in preterm infants born small for gestational age

Area of Science:

• Endocrinology
• Neonatal studies
• Reproductive medicine

Background:

• Infants born small for gestational age (SGA) face increased risks for conditions like testicular dysgenesis syndrome in boys and polycystic ovary syndrome in girls.
• Understanding the hormonal milieu at birth for SGA infants is crucial for predicting long-term health outcomes.

Purpose of the Study:

• To investigate whether neonates born small for gestational age (SGA) present with an altered steroid hormone profile at birth.
• To identify specific hormonal differences between SGA and appropriate for gestational age (AGA) infants.

Main Methods:

• A cohort of 168 moderate-to-late preterm singletons (32.0-36.9 weeks gestational age) was studied.
• Umbilical cord serum from 31 SGA infants (17 boys, 14 girls) and appropriate for gestational age (AGA) infants was analyzed.
• Concentrations of key steroid hormones including DHEAS, androstenedione, testosterone, dihydrotestosterone, estrone, estradiol, cortisone, and cortisol were measured using mass spectrometry.

Main Results:

• Girls born SGA showed significantly higher androstenedione levels compared to AGA girls (p=.002).
• Boys born SGA exhibited significantly lower estrone levels than AGA boys (p=.038).
• All SGA infants, both boys and girls, had lower cortisone levels (p=.010 and p=.045, respectively), and SGA boys had a higher cortisol/cortisone ratio (p=.028).
• Gestational age positively correlated with DHEAS and cortisol levels in both sexes.

Conclusions:

• Moderate-to-late preterm infants born SGA display a distinct cord serum steroid hormone profile.
• Elevated androstenedione in SGA girls and reduced estrone in SGA boys may indicate potential links to placental aromatase deficiency in intrauterine growth restriction.
• These hormonal alterations at birth warrant further investigation regarding their long-term implications for reproductive health.