Dr Michael W. O'Reilly FRCPI PhD

Dr Michael W. O'Reilly

Institute of Metabolism and Systems Research
Honorary Senior Lecturer

Contact details

University of Birmingham
B15 2TT

Michael is a Hoffenberg Clinician Scientist in Metabolic Endocrinology in the Institute of Metabolism and Systems Research. His research focuses on the metabolic consequences of androgen excess in women. He has a clinical subspecialist interest in polycystic ovary syndrome, adrenal tumours and endocrine infertility.


  • FCRCP (Ireland) 2018
  • PhD (2015)
  • CCT in Endocrinology/Diabetes/GIM (2014)
  • Member of the Royal College of Physicians of Ireland 2007
  • Bachelor of Medicine (Honours) National University of Ireland Galway 2005


Career history:

August 2015: August 2015: Honorary Consultant Endocrinologist and Lead Clinician, Adrenal MDT, University Hospital Birmingham

2012-2015: PhD student and Wellcome Clinical Research Fellow, UOB

2011-2012: Clinical Research Fellow (UOB, RCPI research bursary)

2008-11: Specialist training Endocrinology/Diabetes/General Medicine

2005-08: Foundation and Core Medical Training, Rep. of Ireland

1999-2005: Medical degree, National University of Ireland Galway (NUIG)


  • Session Facilitator, Adrenal disorders, Society for Endocrinology Clinical Endocrine Update 2018-present
  • Adrenal lecturer to 1st year MB ChB
  • Small Group tutorials 1st and 2nd year MB ChB
  • Senior Medical Examiner Final Medical exams

Postgraduate supervision

Joint PhD supervisor, Dr. Punith Kempegowda

Membership candidate tutorials MRCP(UK)



I am particularly interested in the metabolic complications of androgen excess in women, with a focus on adipose tissue dysfunction, using in vivo and in vitro models. I also study the sexually dimorphic impact of androgens on human metabolic health, looking specifically at the overlapping adverse metabolic phenotype of women with androgen excess and men with androgen deficiency.

Major collaborators 

Dr Alex Sinclair, Professor Rick Dunne, Professor Jeremy Tomlinson, Dr Krish Nirantharakumar, Dr Mark Sherlock, Professor Chris Thompson


Other activities

  • Lead Clinician, Adrenal MDT and clinic, University Hospital Birmingham
  • Lead Consultant, Andrology clinic, University Hospital Birmingham


O’Reilly M.W*, Hornby C*, Westgate C.S.J, Botfield H, Taylor A.E, Markey K, Mitchell J, Scotton W.J, Mollan S.P, Yiangou A, Jenkinson C, Gilligan L.C, Sherlock M, Gibney J, Tomlinson J.W, Hodson D.J, Arlt W, Sinclair A.J (*joint first authors) (2019) A unique androgen excess signature in idiopathic intracranial hypertension is linked to cerebrospinal fluid dynamics  JCI Insight. Feb 12. pii: 125348. doi: 10.1172/jci.insight.125348. [Epub ahead of print]

O'Reilly M.W, Glisic M, Kumarendran B, Subramanian A, Manolopoulos K.N, Tahrani A.A, Keerthy D, Muka T, Toulis K.A, Hanif W, Thomas G.N, Franco O.H, Arlt W, Nirantharakumar K (2019) Serum testosterone, sex hormone-binding globulin and sex-specific risk of incident type 2 diabetes in a retrospective primary care cohort Clin Endocrinol (Oxf).Jan; 90(1):145-154.

Kumarendran B*, O'Reilly M.W*, Manolopoulos K.N*, Toulis KA, Gokhale K.M, Sitch A.J, Wijeyaratne C.N, Coomarasamy A, Arlt W, Nirantharakumar K (2018) (*joint first authors) Polycystic ovary syndrome, androgen excess, and the risk of nonalcoholic fatty liver disease in women: A longitudinal study based on a United Kingdom primary care database. PLoS Med. Mar 28; 15(3):e1002542.

Elhassan Y.S, Idkowiak J, Smith K, Asia M, Gleeson H, Webster R, Arlt W, O'Reilly M. W (2018) Causes, Patterns, and Severity of Androgen Excess in 1205 Consecutively Recruited Women. J Clin Endocrinol Metab.Mar 1; 103(3):1214-1223.

O'Reilly M.W, Kempegowda P, Walsh M, Taylor A.E, Manolopoulos K.N, Allwood J.W, Semple R.K, Hebenstreit D, Dunn W.B, Tomlinson J.W, Arlt W (2017) AKR1C3-Mediated Adipose Androgen Generation Drives Lipotoxicity in Women With Polycystic Ovary    Syndrome. J Clin Endocrinol Metab.Sep 1;102(9):3327-3339

O’Reilly M.W, House P.J, Tomlinson J.W (2014) Understanding androgen action in adipose tissue. J Steroid Biochem Mol Biol Sep; 143: 277-84

O’Reilly M.W, Taylor A.E, Crabtree N.J, Hughes B.A, Capper F, Crowley R.K, Stewart P.M, Tomlinson J.W, Arlt W (2014) Hyperandrogenemia predicts metabolic phenotype in PCOS: the utility of serum androstenedione. J Clin Endocrinol Metab  March; 99 (3): 1027-1036.

O’Reilly M.W, Sexton D.J, Dennedy M.C, Counihan T.J, Finucane F.M, O’Brien T.J, O’Regan A.W (2015) Radiologic remission and recovery of thirst appreciation after adipsic diabetes secondary to neurosarcoidosis. QJM Aug; 108 (8): 657-9

O’Reilly M.W, Avalos G, Dennedy M.C, O’Sullivan E.P, Dunne F (2011) Atlantic DIP  High prevalence of abnormal glucose tolerance postpartum is reduced by breast-feeding in women with prior gestational diabetes mellitus. Eur J Endocrinol Dec; 165 (6): 953-9

Oostdijk W, Idkowiak J, Mueller J.W, House P.J, Taylor A.e, O’Reilly M.W, Hughes B.A, de Vries M.C, Kant S.G, Santen G.W, Verkerk A.J, Uitterlinden A.G, Wit J.M, Losekoot M, Arlt W (2015) PAPSS2 deficiency causes androgen excess via impaired DHEA sulfation – in vitro and in vivo studies in a family harbouring novel PAPSS2 mutation. J Clin Endocrinol Metab Apr; 100 (4):277-8

For a full list of Dr M.W O'Reilly's publications

View all publications in research portal