The role of sleep duration and quality in vitamin D metabolism and their association with glucose homeostasis in pregnancy

Date of Award


Document Type



Edith Cowan University

Degree Name

Doctor of Philosophy


School of Nursing and Midwifery

First Supervisor

Lisa Whitehead

Second Supervisor

Diana Arabiat

Third Supervisor

Aisling Smyth


Pregnancy due to several factors may predispose women to insufficient and poor sleep quality. Sleep is an important regulator of body metabolism and energy homeostasis. Vitamin D, along with its classical action in mineral homeostasis plays an important role in metabolic regulation. Both sleep deprivation and vitamin D deficiency have been linked independently and separately to hyperglycemia and pathogenesis of type 2 diabetes. To date, the potential association between sleep, vitamin D level and glycemic level in pregnancy have received little attention. This study aimed to investigate the relationship between subjectively and objectively measured night-time sleep duration and quality, vitamin D level and glucose homeostasis in pregnancy and birth outcomes. Forty-two women were enrolled in this study. Maternal blood glucose, insulin and 25 (OH)D were measured at 24-28 weeks of pregnancy. Sleep outcomes were measured using Actigraphy, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Birth outcomes were extracted from medical records post-delivery. The results of this study showed that low serum levels of 25(OH)D levels are associated with longer sleep duration while blood glucose levels and insulin resistance and secretion are associated with poorer sleep outcomes, including daytime dysfunction, sleep efficiency and sleep disturbances. Our findings confirmed the association between vitamin D level and sleep and glucose homeostasis during pregnancy.Furthermore,we found that, sleep duration greater than 8 hours in the second trimester of pregnancy and pre-pregnancy BMI are associated with shorter gestational duration. Maternal 25(OH)D level is associated with the 5-minute APGAR score. Our findings add to the existing literature on the role of vitamin D deficiency and its association with APGAR scores, though further studies are needed to establish causation.

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