Parturition Itself Is the Basis for Fetal Adrenal Involution

• Published in: The journal of clinical endocrinology and metabolism 2007-01, Vol.92 (1), p.93-97
• Main Authors: Ben-David, Shlomit, Zuckerman-Levin, Nehama, Epelman, Monica, Shen-Orr, Zila, Levin, Moshe, Sujov, Polo, Hochberg, Ze’ev
• Format: Article
• Language: English
• Subjects: Adrenal Glands - diagnostic imaging; Adrenal Glands - embryology; Adrenal Glands - growth & development; Androstenedione - blood; Biological and medical sciences; Dehydroepiandrosterone Sulfate - blood; Endocrinopathies; Female; Fundamental and applied biological sciences. Psychology; Gestational Age; Humans; Hydrocortisone - blood; Infant, Newborn; Male; Medical sciences; Parturition - physiology; Pregnancy; Ultrasonography; Vertebrates: endocrinology
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.2005-2720

Context: Newborn infants show a postnatal decline in androgen levels as the fetal adrenal glands involute. Hypothesis: Placental factors up-regulate dehydroepiandrosterone sulfate (DHEA-S) generation. Hence, regardless of age, parturition will result in fetal adrenal involution and decline in DHEA-S levels. Subjects and Methods: Premature neonates (n = 30) with gestational age 26–35 wk were studied. Adrenal volume by ultrasonography and serum DHEA-S, cortisol, and androstendione levels were followed weekly between d 1 and 28 of life. Results: Serum DHEA-S was high on d 1 of life, declining rapidly regardless of gestational age during the first week of life (P < 0.001), and serum androstenedione and cortisol levels followed a similar pattern. Androstenedione levels showed a rise as of d 21 of life in boys but not in girls. The adrenals decreased in ultrasonographic volume from d 1 to 14 of life (P < 0.001), regardless of gestational age. Conclusions: Involution of the adrenal is faster than previously reported and, regardless of gestational age, occurs within the first week of life in terms of hormone secretion and within 2 wk in adrenal size. Involution involves a decline in DHEA-S but also in androstenedione and cortisol secretion, with a change in enzymatic activity. Males and females differ in their androstenedione levels and enzymatic activity. Parturition itself is the basis for fetal adrenal involution, supporting a key role for placental factors in maintaining the fetal adrenal and generating adrenal androgens.