Pregnant women who are overweight or obese are particularly vulnerable to vitamin D insufficiency owing to the higher physiological requirement and lower status (25-hydroxyvitamin D, 25(OH)D concentrations) associated with obesity. Vitamin D is involved in calcium and phosphate homeostasis and is essential for the maintenance of bone health. Maternal vitamin D supply is the main source of fetal vitamin D and vitamin D status of the neonate has been shown to be highly correlated with maternal vitamin D status, accounting for 60-80% of infants’ status at delivery. Vitamin D deficiency during pregnancy is associated with poor fetal and postnatal growth and it has been observed that neonates of obese mothers had significantly lower vitamin D status in cord blood compared to neonates of normal weight mothers despite no difference in maternal 25(OH)D status. During pregnancy, the maternal physiology adapts to meet the increased calcium demands of the fetus. The effect of this adaptation on maternal and fetal bone status, particularly in the context of obesity, combined with a low vitamin D status is not fully understood.
While numerous studies have examined vitamin D supplementation in pregnancy, none have examined the impact of obesity on bone turnover markers in response to vitamin D supplementation throughout pregnancy. We have recently completed a large intervention study in pregnant women to assess the effect of supplementation (10μg-vs-20μg vitamin D3/d) throughout pregnancy (from 12 weeks gestation until delivery) on vitamin D status of normal weight, overweight and obese pregnant women and on infant cord blood, using a double-blind randomised vitamin D intervention study (MO-VITD). Based on our findings of the high prevalence of vitamin D insufficiency in early pregnancy, maternal vitamin D supplementation of 20µg/d may be advisable to maintain maternal vitamin D status in pregnant women in Northern Ireland.
This PhD will be a continuation of our work and will aim to investigate the impact of obesity and vitamin D supplementation on the associated maternal and fetal bone turnover markers.
This aim will be addressed through the completion of the following analysis:
1. The association between maternal adiposity, vitamin D status and bone turnover markers: a systematic review.
2. To investigate the impact of maternal adiposity on bone turnover marker status in early pregnancy.
3. To investigate the effect of supplementation of 10μg vs 20μg vitamin D3/d on maternal and fetal bone turnover markers in normal weight, overweight and obese pregnant women.
4. To assess the impact of supplementation of 10μg vs 20μg vitamin D3/d during pregnancy on bone density in the offspring (MOVITD follow-up study).
Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.
We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.
In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.
If the University receives a large number of applicants for the project, the following desirable criteria may be applied to shortlist applicants for interview.
The University offers the following levels of support:
The following scholarship options are available to applicants worldwide:
These scholarships will cover full-time PhD tuition fees for three years (subject to satisfactory academic performance) and will provide a £900 per annum research training support grant (RTSG) to help support the PhD researcher.
Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.
Please note: you will automatically be entered into the competition for the Full Award, unless you state otherwise in your application.
The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £19,000 (tbc) per annum for three years (subject to satisfactory academic performance).
This scholarship also comes with £900 per annum for three years as a research training support grant (RTSG) allocation to help support the PhD researcher.
Due consideration should be given to financing your studies. Further information on cost of living
Submission deadline
Friday 7 February 2020
12:00AM
Interview Date
9 to 20 March 2020
Preferred student start date
Mid September 2020
Telephone
Contact by phone
Email
Contact by email