The Role of Vitamin D in Fertility and In Vitro Fertilisation (IVF) Outcomes

The objective of this cross-sectional observational study is to examine the correlation between total Vitamin D levels in blood serum, follicular fluid and semen with various parameters of male and female fertility including oocytes generated, and rates of fertilisation, pregnancy, birth and miscarriage. In addition, in vitro/ex vivo investigations will be performed to determine the relationship between Vitamin D status, and the bioenergetic profile of sperm and granulosa cells. For females, blood samples are routinely collected before and during IVF cycles to monitor estrogen and progesterone levels as per standard fertility assessment and treatment. An aliquot of these samples from consenting patients will be used to determine Vitamin D status (25 hydroxy vitamin D). Follicular fluid and the granulosa cells within it will be collected from consenting patients as they undergo oocyte collection using transvaginal oocyte aspriation at the clinic. For consenting males, an aliquot of semen will be collected for vitamin D testing and sperm testing following assessment of diagnostic semen parameters and/or insemination of all oocytes retrieved, Therefore the sample that is tested for Vitamin D and sperm function as part of this study is not required for further patient tests or use. To assess the lengthiest outcome, live birth rate, patient data will be observed up to 12 months (1 year), so that live birth outcomes can be recorded.