신생아내분비학은 아직 미개척분야이나, 여기에 관한 최근의 지견을 망라하며 논술하였다.

The problems of fetal endocrinology remain to be solved. In this paper current concepts of fetal endocrinologic field were briefly reviewed as follows. 1) Fetal pituitary The release of pituitary. hormones( ACTH, MSH, GH, PRL, TSH, FSH, LH) is detected as early as 5 weeks fetal life. Fetal pituitary is a dynamic endocrine organ through out gestation and may play an active role in normal fetal development. 2) Fetal adrenal Though the fetal adrenal cortex(probably the fetal zone) is relative deficient in Δ5-3βhydroxysteroid dehydrogenase, the abundance of placental progesterone makes it unlikely that fetal cortex (after about 8 to 10 weeks` gestation) is unable to form cortisol. The 17, 21 and 11 β-hydroxylases are present and active after 10 weeks` gestation. In addition. the 16 α-hydroxylase is extremely active in the fetal adrenal cortex. The hCG produced during the first months of pregnancy stmulates adrenal growth. Maintenance of the adrenal cortex after the fourth to fifth months of gestation (when hCG production decreases) would depend on pituitary ACTH. In essence, in the first months of gestation cortisol is synthesized mostly placental progesterone, but in the second half of pregnancy cortisol in fetal adrenal cortex is synthesized from pregnenolone. Conversion of cortisol from pregnenolone is mediated by 3β-ol-dehydrogenase and hydroxylation of C11, C17 and C21. The rise of fetal cortisol in human labor is a result of the stress of labor. The chromaffin cells are recognized in adrenal glands of the 27-mm human fetus and in all subsequent stages of development. The fetal adrenal medulla is probably incapable of forming significant quantities of epinephrine. 3) Fetal gonads The active steroidogenesis in the fetal testis in contrast to the quiescent ovary provides further evidence for the essential role of the testis in male differentiation. 4) Fetal thyroid The activity of fetal thyroid begins from 10 weeks` gestation (follicle forming stage). There is suggestive evidence that fetal TSH influences the rate of thyroid maturation. The primitive thyrotrophic cell may appear at 13 weeks` gestation. This is approximately the time when the thyroid, gland begins to trap iodide. Fetal pituitary TSH is detected in 12 weeks` gestation. 5) fetal parathyroid The human fetal parathyroid gland may begin to function from 12 weeks` gestation. 6) Fetal pancreas. Insulin contents in fetal pancreas increases continuously as gestational age progresses, but its basic secretion may be suggested as fetal end life. From several days after birth, the regulatory mechanism of glucose may be accomplished.