Influence of pregnancy and lactation on vitamin D serum levels and antioxidant status in randomized women in Zaria

Pregnancy and lactation are normal physiological conditions that tend to influence numerous biological processes. The aim of this study was to identify the impact of pregnancy and lactation on serum vitamin D level and antioxidant status in some women in Zaria, Nigeria. A cross‑sectional descriptive study conducted at Ahmadu Bello University Teaching Hospital, Zaria for a period of three (3) months. Blood samples were collected, serum catalase, superoxide dismutase, lipid peroxidation and vitamin D, were determined using standard methods. Data were presented as mean ± SD, analysis was performed using one-way ANOVA and Pearson's correlation analysis. Values were considered significant at p ≤ 0.05. There was a significant difference (p < 0.01) serum malondialdehyde level, superoxide dismutase activity and glutathione peroxidase activity during the various trimesters of pregnancy and lactating group. However, the levels of these markers were highest in the lactating group. Furthermore, serum level of vitamin D and catalase activity was highest in the 2nd trimester and lowest in the control and lactating group respectively.  Pregnancy and lactation altered serum level of Vitamin D, CAT, SOD, MDA and GPx suggesting a variation in oxidative stress at different trimester of pregnancy and lactation. Key words: Pregnancy, lactation, oxidative stress, vitamin D.

Physiological Changes in Serum Calcium, Phosphate, Vitamin D, Parathyroid Hormone and Calcitonin During Pregnancy and Lactation in Randomised Population of Zaria Women

Pregnancy and lactation are usual but stressful physiological conditions accompanied by changes in calcium and phosphate metabolism and their regulatory hormones which may lead to calcium-related disorders in pregnant women. This study aimed to evaluate the changes in serum levels of calcium, phosphate, vitamin D and their regulatory hormones in pregnant and lactating women in Zaria, Nigeria. A cross‑sectional descriptive study was conducted at Ahmadu Bello University Teaching Hospital, Zaria for three (3) months. Blood samples were collected, anthropometric measurements (weight, height and body mass index) of 179 women were taken. Serum calcium, phosphate, vitamin D, parathyroid hormone and calcitonin were determined using standard methods. Data were presented as mean ± SD, analysis was performed using one-way ANOVA and Pearson's correlation analysis. Values were considered significant at p ≤ 0.05. There was a significant decrease in serum calcium concentration (p < 0.01) during the third trimester of pregnancy and lactation. An increase in serum concentration of vitamin D, parathyroid hormone, and calcitonin in the 2nd trimester and a decrease during the third trimester and lactation although not statistically significant when compared with the control. There was a negative correlation between serum calcium concentration and gestational age (r = 0.255) while no correlation between gestational age and serum phosphate concentration. Changes in serum calcium, vitamin D, parathyroid hormone and calcitonin during pregnancy and lactation has been demonstrated suggesting a relationship between calcium metabolism and these hormones at some stages of pregnancy.