CORD SERUM THYROID STIMULATING HORMONE (TSH) AND THYROGLOBULIN (Tg) LEVELS DECLINE WITH INCREASING BIRTH WEIGHT IN NORMAL FEMALE NEWBORNS

SUMMARY The NADP-dependent microsomal kidney enzymes, 3α- and 20β-hydroxysteroid dehydrogenase (HSDH), which exhibit considerable sex differences in their activities (male: female activity ratios, 16:1 and 30:1 respectively), were investigated after interference with the pituitary–gonad and pituitary–adrenal systems. Prepubertal gonadectomy as well as hypophysectomy of mature male rats led to a decline in HSDH activity to almost that found in the normal female rat, whereas activities in female rats were unaffected. Testosterone induced typical male 3α-HSDH activity in both gonadectomized and hypophysectomized rats of either sex. Administration of 5α-dihydrotestosterone (5α-DHT) or 5α-androstane-3α, 17β-diol to hypophysectomized male rats was equally effective in restoring full 3α- and 20β-HSDH activities whereas 5α-androstane-3β, 17β-diol was less effective and dehydroepiandrosterone was ineffective. Simultaneous administration of cyproterone acetate did not block the inductive action of 5α-DHT. Administration of chorionic gonadotrophin, pregnant mare serum gonadotrophin or a combination of luteinizing hormone and follicle-stimulating hormone to hypophysectomized male rats all led to parallel increases in the weight of the seminal vesicles and in both renal enzyme activities; administration of growth hormone, prolactin or thyroid-stimulating hormone was ineffective. Adrenalectomy of gonadectomized, but not of hypophysectomized male rats, caused a further drop in activity to the normal female level. Adrenalectomy of otherwise intact rats did not affect either enzyme activity. The hypophysis was involved in the regulation of the two NADP-dependent renal HSDH activities through its gonadotrophic function in male rats; adrenal secretions were of little physiological significance.

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Free thyroxine and thyroid-stimulating hormone reference intervals in very low birth weight infants at 3–6weeks of life with the Beckman Coulter Unicel DxI 800

Clinical Biochemistry ◽

10.1016/j.clinbiochem.2013.10.005 ◽

2014 ◽

Vol 47 (1-2) ◽

pp. 16-18 ◽

Cited By ~ 6

Author(s):

Xiaoli Sun ◽

Brigitte Lemyre ◽

Xiaoqin Nan ◽

JoAnn Harrold ◽

Sherry L. Perkins ◽

...

Keyword(s):

Birth Weight ◽

Low Birth Weight ◽

Very Low Birth Weight ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Low Birth Weight Infants ◽

Stimulating Hormone

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Maternal Low Levels Of Thyroid Stimulating Hormone (TSH) With Low Birth Weight In Magelang District

International Journal of Scientific and Research Publications (IJSRP) ◽

10.29322/ijsrp.11.05.2021.p11331 ◽

2021 ◽

Vol 11 (5) ◽

pp. 269-272

Author(s):

Riska Epina Hayu

Keyword(s):

Birth Weight ◽

Low Birth Weight ◽

Thyroid Stimulating Hormone ◽

Low Levels ◽

Stimulating Hormone

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Prediction of later development of thyrotoxicosis or central hypothyroidism from the cord serum thyroid-stimulating hormone level in neonates born to mothers with Graves disease

The Journal of Pediatrics ◽

10.1016/s0022-3476(89)80093-9 ◽

1989 ◽

Vol 115 (2) ◽

pp. 318-321 ◽

Cited By ~ 31

Author(s):

Haruo Tamaki ◽

Nobuyuki Amino ◽

Keiko Takeoka ◽

Yoshinori Iwatani ◽

Junko Tachi ◽

...

Keyword(s):

Hormone Level ◽

Thyroid Stimulating Hormone ◽

Graves Disease ◽

Central Hypothyroidism ◽

Cord Serum ◽

Stimulating Hormone

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Associations of Exposure to Perfluoroalkyl Substances With Thyroid Hormone Concentrations and Birth Size

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgz147 ◽

2019 ◽

Vol 105 (3) ◽

pp. 735-745 ◽

Cited By ~ 3

Author(s):

Christina Xiao ◽

Philippe Grandjean ◽

Damaskini Valvi ◽

Flemming Nielsen ◽

Tina Kold Jensen ◽

...

Keyword(s):

Birth Weight ◽

Thyroid Hormone ◽

Thyroid Function ◽

Positive Association ◽

Thyroid Stimulating Hormone ◽

Maternal Serum ◽

Perfluoroalkyl Substances ◽

Birth Size ◽

Negatively Associated ◽

Cord Serum

Abstract Background Adequate thyroid function during pregnancy is essential for optimal fetal growth. Gestational exposure to perfluoroalkyl substances (PFAS) can negatively affect birth size and disrupt maternal and neonatal thyroid function, although the interrelationship is unclear. Objective We aimed to quantify the associations between maternal serum–PFAS concentrations and birth weight, birth length, and cranial circumference. We also aimed to estimate associations between PFAS and thyroid hormone (TH) concentrations, thereby elucidating whether THs potentially mediate the associations between PFAS concentrations and birth size. Methods We studied a population-based prospective cohort of 172 mother-singleton pairs from the Faroe Islands. Twelve PFAS were measured in maternal serum obtained at 34 weeks of gestation. THs were measured in maternal and cord serum. Associations between PFAS concentrations and birth size and TH concentrations were estimated using multivariable linear regressions. Sex-stratified analyses along with a mediation analysis were performed to estimate potential mediating effects of THs in the association between PFAS and birth outcomes. Results Several PFASs were negatively associated with birth weight, length, and head circumference, and a general positive association between maternal serum–PFASs and cord serum–thyroid-stimulating hormone (TSH; also known as thyrotropin) was found. For instance, a doubling in perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) was associated with a 53% (95% CI, 18%-99%) and 40% (95% CI, 8%-81%) increases in TSH concentrations, respectively. There was little evidence of sexually dimorphic associations. Overall, THs were not found to mediate associations between PFASs and birth size. Conclusion In this study, several PFASs were negatively associated with birth size and increased THs; however, this did not explain lower birth weight among children exposed to PFAS.

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