The thyroid gland in women during the reproductive age

OBJECTIVE: To find out thyroid volume and its functional status in women in reproductive age as well as possible correlation between thyroid size and functional status and age and residential location of women. DESIGN: Project can be characterized as an epidemiological study and consists of three separate observations. SETTING: 1st Internal Clinic, UPJS, Kosice, Medical Faculty, Slovakia. METHODS: 347 women from different regions of Eastern Slovakia (160 aged 20-29 and 187 aged 30-40) were measured thyroid volume via ultrasonography and thyroid functional status by RIA TSH and anti TPO examinations. Urinary iodine was examined in 70 cases. In this part of the study correlation between thyroid size and functional status and age and residential location of women were determined. Four days after delivery thyroid volume in 99 women was measured. The volume was correlated with the number of previous pregnancies. Thyroid volume was correlated with residential location and number of pregnancies of 77 women that had not delivered in the previous year. RESULTS: Women aged 20-29 years had thyroid volume smaller than women aged 30-40 (8.78 ml/10.66 ml; p < 0.01). The size of thyroid gland was not only affected by age but also by residential location. The largest thyroid glands and increased level of anti TPO antibodies in both age groups were found in women from agricultural regions and regions close to chemical factory. The women with anti TPO antibodies had increased level of TSH as well as more frequently changed echogenity of thyroid gland. Median of urinary iodine was 13.2 micrograms/dl in both age groups and indicated sufficient iodine intake in the observed area. The volume of thyroid gland four days after delivery did not exceed 22 ml in 89.9% of cases. Significant difference in size of thyroid gland depending on number of previous deliveries was not only observed in women 4 days after delivery but also in those that had not delivered during previous year. The largest volumes were measured in secundiparous mothers. CONCLUSION: Polluted environment affects the size and functional status of thyroid gland. Environment can via this negative impact on thyroid gland influence fertility, pregnancy and fetus development in women in reproductive age.