CONTEXT: Gestational diabetes mellitus (GDM) is a common pregnancy complication, particularly in women undergoing assisted reproductive technology (ART). An association of GDM with vitamin D in women conceiving naturally has been described; however, studies have yielded heterogeneous results. OBJECTIVE: To analyze the association between prepregnancy total and free vitamin D and GDM incidence in women undergoing ART. METHODS: Post hoc analysis of a prospective study at the Reproductive and Genetic Hospital of CITIC-Xiangya in Changsha, China. Total and free vitamin D were measured 1 day before embryo transfer. The patients were screened for GDM using the oral glucose tolerance test. RESULTS: A total of 1593 women were included in the study, among whom 256 (16.1%) developed GDM. According to international guidelines for total 25-hydroxyvitamin D [25(OH)D], 47 (2.9%) patients had sufficient (≥30 ng/mL) levels, while 696 (43.7%) were insufficient (20 to <30 ng/mL) and 850 (54.4%) were deficient (<20 ng/mL). Comparing GDM and non-GDM patients, there was no significant difference in total nor free vitamin D levels (P = .340 and .849). Similarly, analysis of GDM rates by quintiles of total and free 25(OH)D showed no significant association in one-way ANOVA (P = .831 and .799). Multivariate logistic regression, considering age, BMI, and fasting glucose, also did not show a significant influence of the 2 vitamin D forms on GDM incidence (P = .266 and .123 respectively). CONCLUSION: In this relatively vitamin D deficient/insufficient ART cohort, the degree of neither total nor free vitamin D deficiency before pregnancy was associated with the occurrence of GDM.

• Klíčová slova
• free vitamin D, gestational diabetes, in vitro fertilization, vitamin D,
• Publikační typ
• časopisecké články MeSH

Vitamin D is a micronutrient with pleiotropic effects in humans. Due to sedentary lifestyles and increasing time spent indoors, a growing body of research is revealing that vitamin D deficiency is a global problem. Despite the routine measurement of vitamin D in clinical laboratories and many years of efforts, methods of vitamin D analysis have yet to be standardized and are burdened with significant difficulties. This review summarizes several key analytical and clinical challenges that accompany the current methods for measuring vitamin D. According to an external quality assessment, methods and laboratories still produce a high degree of variability. Structurally similar metabolites are a source of significant interference. Furthermore, there is still no consensus on the normal values of vitamin D in a healthy population. These and other problems discussed herein can be a source of inconsistency in the results of research studies.

• Klíčová slova
• LC–MS/MS, VDR, determination, genomic effects, metabolites, non-genomic effects, vitamin D,
• MeSH
• hodnocení stavu výživy * MeSH
• klinické laboratorní techniky metody   normy   MeSH
• laboratoře normy   MeSH
• lidé MeSH
• nedostatek vitaminu D diagnóza   MeSH
• referenční hodnoty MeSH
• referenční standardy MeSH
• reprodukovatelnost výsledků MeSH
• vitamin D analýza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• vitamin D MeSH