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Parathyroid Hormone in Pregnancy: Vitamin D and Other Determinants.

ABSTRACT: We aimed to assess the parathyroid hormone (PTH) concentration in pregnant women at the beginning of pregnancy (1st trimester) and within days before delivery (3rd trimester) and evaluate its determinants. From September 2014 through December 2015 in a cross-sectional study, 204 women in the 1st trimester of pregnancy and 203 women in the 3rd trimester of pregnancy were recruited. Blood samples were collected to measure PTH and circulating 25-hydroxy-vitamin D (25(OH)D) concentrations. Lifestyle and demographic data were collected using a questionnaire. Serum 25(OH)D and PTH were inversely correlated in both early and late pregnancy. Our analyses suggest that in the 3rd trimester of pregnancy, a 25(OH)D level of 18.9 ng/mL (47.3 nmol/L) could serve as an inflection point for the maximal suppression of PTH. Statistically significant determinants of PTH concentrations in multiple regression were 25(OH)D concentrations, season, multiparity and education of the partner (all p < 0.05) in early pregnancy. In late pregnancy, 25(OH)D concentrations and country of origin were statistically significant determinants of PTH concentrations (all p < 0.05). These factors and their effect on PTH appear to be vastly determined by 25(OH)D; however, they might also affect PTH through other mechanisms besides 25(OH)D.

SUBMITTER: Hysaj O

PROVIDER: S-EPMC7911996 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Parathyroid hormone in Sri Lankan pregnant women: Vitamin D and other determinants.

Project description:IntroductionDeterminants of parathyroid hormone level during pregnancy have been less frequently studied. We aimed to describe the serum parathyroid hormone (PTH) and its determinants in Sri Lankan pregnant women in a community setting.Materials and methodsIn this cross-sectional analysis, 390 pregnant mothers in their third trimester were enrolled from primary care centers of 15 health divisions in the Colombo District in Sri Lanka. Venous blood was analyzed for a total 25-hydroxyvitamin-D [25(OH)D], serum parathyroid hormone (PTH), serum calcium, and alkaline phosphatase. The bone quality was assessed in terms of speed of sound (SOS) using the quantitative ultrasound scan (QUS). Univariate and multivariate regression analysis was used to examine the determinants of PTH concentration in blood.ResultsMedian serum 25(OH)D was 17.5ng/mL. Most (61.6%) were vitamin D deficient (<20ng/mL). Median PTH was 23.7pg/mL. Only 0.8% had hyperparathyroidism (PTH >65pg/mL). The correlation between 25(OH)D and PTH was weak but significant (r = -0.197; p<0.001). SOS Z-score was below the cut-off (≤-2) in fifty-six women (14.7%), and SOS did not relate significantly to PTH. In regression analysis, serum 25(OH)D, serum calcium, body mass index, educational level, and weeks of pregnancy were significant independent variables when adjusted. The model explained 16% of the variation in the PTH level.ConclusionsA high prevalence of vitamin D deficiency was observed among Sri Lankan pregnant women in the present study. Serum 25(OH)D, calcium, weeks of pregnancy, and educational level were determinants of serum PTH.

| S-EPMC8500411 | biostudies-literature

Association of Vitamin D and Parathyroid Hormone With Barrett's Esophagus.

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Project description: Not available

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Parathyroid hormone reference ranges in healthy individuals classified by vitamin D status.

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Parathyroid hormone decreases renal vitamin D receptor expression in vivo.

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Reduction of Parathyroid Hormone with Vitamin D Supplementation in Blacks: A Randomized Controlled Trial.

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| S-EPMC4743037 | biostudies-literature