Endocrine Abstracts

About 7% of pregnancies are complicated by diabetes, out of which 97.5% gestational diabetes (GMD), 2.5% pre-gestational diabetes. We investigated 29 women at their first pregnancy who had GMD medium risk factor in the absence of pre-existing thyroid pathologies. We divided them in two groups: the first 19 women (age 33.9 years) resulted affected by GMD (OGTT effected, according to Carpenter and C criteria), between pregnancy weeks 24–28; the second ten women (age 34.3 years) showed a normal OGTT (control group). In all the patients the thyroid hormones were investigated. Normal mean values of FT₃ and TSH, negative TPO and low mean values of FT₄ 0.8 (0.71–1.85 ng/dl) have been evidenced in the first group. In the control group the mean value of FT₄ was 1.04. During the pregnancy the low values of FT₄ are normally due to a reduced iodine intake (mild thyroid failure) which may have possible effects on the fetal neurological system. In the first group, 11 patients, had been using iodized salt for more than 2 years (mean FT₄ 0.80 ng/dl), in the second group, eight patients, had never been using it (mean FT₄ 0.78 ng/dl); in the control group, five patients had been using iodized salt (mean FT₄ 1.1), and five had not (mean FT₄ 0.9). In the GMD the sole use of the iodized salt is not sufficient to keep the FT₄ levels in the normal range and it is furthermore assumable that the insulin resistance may stimulate the inhibitor of the serum binding of thyroid hormones like the free fatty acids.