Effect of cord clamping time on neonatal vitamin B12, folate and urinary iodine concentration

Area of Science:

• Neonatal health and physiology
• Maternal-fetal medicine
• Endocrinology

Background:

• Umbilical cord clamping timing is a critical factor in neonatal adaptation.
• Early or late clamping may influence the transfer of essential nutrients and hormones to the newborn.
• Understanding these effects is crucial for optimizing infant health outcomes.

Purpose of the Study:

• To investigate the impact of early versus late umbilical cord clamping on micro-element and thyroid hormone levels in newborns.
• To compare neonatal thyroid hormone profiles (FT3, FT4, TSH) and vitamin levels (B12, folate) based on clamping time.
• To assess the correlation between maternal and neonatal nutrient levels.

Main Methods:

• A randomized study comparing two groups: early clamping (within 10 seconds) and late clamping (at 60 seconds).
• Measurement of maternal and neonatal free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulant hormone (TSH), urinary iodine concentration (UIC), folate, and vitamin B12.
• Statistical analysis to determine significant differences and correlations between groups.

Main Results:

• Late clamping showed significantly higher FT4 and FT3 levels in newborns within 24 hours compared to early clamping.
• Newborns in the early clamping group had a higher incidence of below-normal FT4 and FT3 levels.
• Vitamin B12 deficiency was significantly more prevalent in the early clamping group, with a positive correlation between maternal and neonatal B12 levels.

Conclusions:

• Late umbilical cord clamping may enhance vitamin B12 and folate transfer to the newborn, potentially supporting erythrocyte synthesis.
• Delayed clamping appears beneficial for maintaining adequate thyroid hormone levels and vitamin B12 status in neonates.
• These findings suggest that optimizing cord clamping timing can positively impact neonatal micronutrient and hormonal status.