DrDavid Crosby

In my current role as Head of Department of Reproductive Medicine at the National Maternity Hospital and Clinical Director at Merrion Fertility Clinic, I co-supervise four MD clinical research fellows and one Aspire Clinical Fellow in Reproductive Medicine.

National Collaborations: Research Projects and Ongoing Clinical Trials

My clinical research group maintains an active and productive research portfolio, collaborating with research groups in UCD School of Medicine, School of Public Health, Physiotherapy and Sports Science and the TCD School of Immunology and Biochemistry.

Research Projects

1) Characterising the endometrial innate immune and microbial landscape in infertility

Maternal uterine immune pathways are necessary for embryo implantation and decidualization and to protect both mother and developing fetus from invasive pathogens. Our research has focused on phenotypic and functional characterisation of uterine natural killer (NK) cells, molecular analysis of endometrial immune signatures around the window of implantation and their overall dysregulation in female infertility and associated inflammatory pathologies. We have extended this work to investigate how uterine innate immune responses are regulated by endometrial commensal bacteria, and how this affects reproductive success.

2) Defining ovarian follicular metabolic mechanisms underlying premature ovarian insufficiency

Diminished ovarian reserve (DOR) poses a particular challenge to fertility specialists, as it correlates with poor response to ovarian gonadotropin stimulation and poor rates of pregnancy and live birth. Dysregulated inflammation has been described in several subfertility aetiologies and may contribute to early decline in ovarian reserve. Mitochondrial depletion and malfunction have also been linked to natural ovarian ageing, but there is little known about how mitochondrial dysfunction may contribute to unexplained premature diminished ovarian reserve. Ongoing transcriptomic (scRNAseq) and proteomic (multiplex) studies of the DOR ovarian follicular microenvironment aim to elucidate immune and metabolic signatures of unexplained premature DOR, to help identify those at risk and facilitate individualized patient counselling and treatment. 

3) Fertility assessment and fertility preservation in adolescents and young adults (AYA)

Survival rates for childhood cancer are now greater than 80%, making efforts to improve quality of life and reduce the long-term sequelae of oncology treatments an increasing priority. Loss of future fertility is an important survivorship issue for young patients. Research by our group aims to develop a national program for AYA fertility preservation in cancer and expand the national standard of care for AYA cancer patients in Ireland. This includes fertility needs assessments for AYA patients and survivors of childhood cancer to identify those who would most benefit from fertility preservation, data collection on cohort ovarian reserve, incidence of premature ovarian insufficiency and testicular failure post cancer treatment, and oocyte and sperm cryopreservation in survivors of childhood cancer.