Cent Eur J Public Health 2024, 32(1):31-38 | DOI: 10.21101/cejph.a7796

Are the elements zinc, copper, magnesium, and rubidium related to nutrition and iodine deficiency in pregnant Bulgarian women from iodine deficient region?

Mariana Georgieva Bacelova¹, Penka Dimitrova Gatseva², Tanya Ivanova Deneva^{3, 4}, Delyana Miteva Davcheva^{3, 4}, Anelia Veselinova Bivolarska⁵

¹ Department of Physiology, Faculty of Medicine, Medical University of Plovdiv, Plovdiv, Bulgaria

² Department of Hygiene, Faculty of Public Health, Medical University of Plovdiv, Plovdiv, Bulgaria

³ Department of Clinical Laboratory, Faculty of Pharmacy, Medical University of Plovdiv, Plovdiv, Bulgaria

⁴ Division of Pharmaceutical Innovations for Personalized Medicine, Research Institute, Medical University of Plovdiv, Plovdiv, Bulgaria

⁵ Department of Medical Biochemistry, Faculty of Pharmacy, Medical University of Plovdiv, Plovdiv, Bulgaria

Objective: Trace elements are essential for the biochemistry of the cell. Their reference values have been found to differ considerably in pregnant women stratified by age, place of residence, anthropometric status, and length of pregnancy. In optimal amounts, these elements reduce the risk of pregnancy complications. Subclinical hypothyroidism in pregnancy is associated with adverse maternal and neonatal outcomes. The aim of the study was to determine the effects of zinc (Zn), copper (Cu), magnesium (Mg), and rubidium (Rb) on pregnant women in an iodine deficiency region and find the relationship with the thyroid status and nutrition.

Methods: We evaluated the iodine status of 61 healthy pregnant women from an iodine deficient region in Bulgaria. Thyroid stimulating hormone (TSH) and thyroxin free (FT4) levels were measured using ELISA.

Results: We found elevated levels of copper that differed the most between the first and second trimesters; Cu and TSH were found to be positively correlated (р < 0.05). Lower Cu levels were found in pregnant women consuming pulses more than 2-3 times a week (р = 0.033). The women consuming fish more than 2-3 times a week had higher levels of Rb. We found a pronounced iodine deficiency in more than half of the examined women in the first to third trimesters, without any effect of pregnancy on the ioduria (р=0.834). All second and third trimester cases were associated with severe ioduria (< 150 µg/L).

Conclusion: The high Cu levels were associated with subclinical hypothyroidism (SCH) and less pulse consumption during pregnancy in an iodine deficiency endemic area. SCH was found in 24% of the pregnant women in such an area while in 13% of them SCH had progressed to overt hypothyroidism.

Keywords: trace elements, subclinical hypothyroidism, iodine-endemic area, pregnant women

Received: March 16, 2023; Revised: March 29, 2024; Accepted: March 29, 2024; Published: March 31, 2024  Show citation