Micronutrient homeostasis disturbances in women with gestational diabetes mellitus and subclinical hypothyroidism: effects on pregnancy and outcomes

Abstract

Aim. To characterize micronutrient homeostasis in women with a combination of gestational diabetes mellitus (GDM) and subclinical hypothyroidism (SCH), and to determine the significance of micronutrient imbalance in complicated pregnancies.Material and Methods. The study analyzed 439 birth histories of patients with GDM and SCH, who underwent plasma micronutrient analysis at 12−13 weeks of gestation. The study examined the patients' anthropometric and medical history data, complications during the current pregnancy, the timing and method of delivery, and newborn conditions. Some of these indicators were compared with previously obtained plasma micronutrient levels (Al, Co, Cu, Fe and others) measured at 12−13 weeks of gestation.Results. The analysis of micronutrient concentrations in plasma at 12−13 weeks of gestation revealed iron deficiency in 250 patients (57%), iodine deficiency in 231 patients (52.6%), cobalt deficiency in 229 patients (52.2%), vitamin B12 deficiency in 285 patients (64.9%), and vitamin D deficiency in 280 patients (63.6%). Iron deficiency was significantly more common in pregnant women with overweight and obesity than in those with normal body weight (χ2 =.14 and 5.32, respectively). The risk of developing iron deficiency also increased with higher body weight (1.81-fold for overweight (95% CI 1.2–2.73) and 2.07-fold for obesity (95% CI 1.11–3.86). Around 50% of patients with threatened preterm birth had cobalt deficiency and 59% of patients with anemia had iron deficiency. Selenium, calcium, and vitamin B12 deficiencies were observed in 55%, 70%, and 73% of patients with preeclampsia (PE), respectively.Conclusion. The observed deficiency of certain micronutrients in specific pregnancy complications suggests that correcting micronutrient levels during pre-conception or early gestation may improve pregnancy outcomes.