Related Experiment Video
Updated: Jul 25, 2026
Substernal Thyroid Biopsy Using Endobronchial Ultrasound-guided Transbronchial Needle Aspiration
Published on: November 10, 2014
Thyroid function in neonates from goitre prevalent areas in Zimbabwe
E Chinyanga1, O Chidede, W B Mujaji
1Department of Chemical Pathology, University of Zimbabwe Medical School, Harare, Zimbabwe.
Insights
Newborn thyroid function in iodine-deficient areas shows success from supplementation. Continued monitoring is vital to ensure full coverage and prevent potential hyperthyroidism risks.
Area of Science:
- Endocrinology
- Public Health
- Neonatal Medicine
Background:
- Iodine deficiency historically impacts thyroid function, particularly in pregnant women and newborns.
- Assessing newborn thyroid hormone levels is crucial for monitoring iodine status and public health interventions.
- Prior to salt iodization, regional variations in iodine deficiency posed risks to neonatal thyroid health.
Purpose of the Study:
- To measure serum thyrotropin (TSH) and free thyroxine (FT4) in newborns from areas with varying iodine deficiency.
- To evaluate the effectiveness of the salt iodization program on neonatal thyroid function.
- To establish baseline thyroid hormone status in newborns before widespread iodine supplementation.
Main Methods:
- Cross-sectional study design.
- Analysis of serum TSH and FT4 concentrations in 500 healthy newborns (2-4 days old).
- Radio-immunoassay techniques used for hormone level determination.
Main Results:
- Slight but significant differences in mean serum FT4 levels were observed between newborns from low and moderate/severe goiter prevalent areas.
- A non-significant trend towards higher TSH values was noted in areas with higher goiter prevalence (p=0.175).
- Median TSH was 4 microU/ml, with 90% of newborns having TSH <10 microU/ml; no sex-based differences in hormone levels.
Conclusions:
- The implemented iodine supplementation program appears successful in improving thyroid hormone status.
- Ongoing monitoring is essential to ensure uniform iodine supplementation nationwide.
- Vigilance is required to prevent potential risks of hyperthyroidism associated with iodine supplementation programs.
Objective:
To measure serum thyrotropin (TSH), and free thyroxine concentrations in newborns delivered in areas with differing degrees of iodine deficiency, (prior to the salt iodization programme), and to use these biochemical indices to assess the current status of thyroid function in the group.
Design:
Cross sectional.
Setting:
Chemical Pathology, University of Zimbabwe, Medical School. Radio-immunoassay laboratory, Parirenyatwa Hospital.
Subjects:
500 healthy full term newborns, aged two to four days old, weighing not less than 2.5 kg.
Main Outcome Measures:
Thyroid hormone status of newborns.
Results:
The mean serum FT4 level was found to be slightly but significantly different between the newborns from Harare region, (low goitre prevalent area), and Wedza district (moderate to severe goitre prevalent area). Although there was a trend in the distribution of TSH to higher values in the moderate to severe goitre prevalent areas, the differences were statistically non significant, p = 0.175. The median TSH value in the newborns was 4 microU/ml. TSH values were below 10 microU/ml in 90%, between 10.1 and 20 microU/ml in 9%, and between 20.1 and 32 microU/ml in 1% of the cases. No sex related differences were observed in either the TSH nor the FT4 values of the newborns.
Conclusion:
This study demonstrates that the iodine supplementation programme has been successful, but further monitoring is necessary to ensure complete supplementation throughout the country and to guard against hyperthyroidism which is known to occur during iodine supplementation programmes.
Related Concept Videos
01:23The Thyroid Gland
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
01:20Synthesis and Regulation of Thyroid Hormones
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
01:18Functions of Thyroid Hormones
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
01:25Hyperthyroidism I: Introduction
01:28Graves' Disease I: Introduction
01:27Goiter