Professor Allan Pacey


Department of Oncology and Metabolism

Professor of Andrology - Head of Departments of Oncology and Metabolism and Infection, Immunity and Cardiovascular Disease
+44 114 215 9665
+44 114 215 9004 (For admin assistance please contact Lindsey Crowson)

Full contact details

Professor Allan Pacey
Department of Oncology and Metabolism
FU19, F Floor
The Medical School
Beech Hill Road
S10 2RX

I was awarded my PhD in 1991 from the University of St. Andrews after which I undertook a one-year Research Fellowship funded by the Royal Society at the Station Zoologique, Villefrance-sur-Mer, France.

I joined the University of Sheffield in 1992, first as a Postdoctoral Research Assistant and then was appointed as lecturer in 1997. In 2001 was appointed as Senior Lecturer in Andrology and in 2015 Professor of Andrology.

I became Head of Department of Oncology and Metabolism in October 2017 and then Head of the Department of Infection, Immunity & Cardiovascular Disease in January 2022.

Research interests

I am interested in the biology of human spermatozoa and aspects of semen quality and fertility in males. It is estimated that 1 in 6 couples have a problem in conceiving a child and in about half of these cases, a problem is identified with the male partner. This may be a result of too few sperm being produced, or the fact that sperm have poor motility (swimming ability) or morphology (size and shape).

In recent years, my research has focussed on how micro-organisms such as Chlamydia trachomatis interact with sperm and affect sperm function.

This is in collaboration with Adrian Eley and has shown that the bacteria can trigger signalling pathways in sperm that lead to premature sperm death. We have investigated the molecular nature of this process and have recently shown that sperm washing methods currently in use in clinics are not effective in removing C. trachomatis from sperm.

In the search for better diagnostic methods in the clinic, I have recently collaborated with engineers from the University of Glasgow (Green/Gilles) and applied modelling techniques used in fluid mechanics to better understand how sperm swim.

This paper was published in the Journal of Fluid Mechanics in 2008 and shows that swimming speed is closely related to the side and shape of the sperm head.

Work with Urologists in Sheffield has developed a new diagnostic test for men who have small numbers of non-motile sperm in their ejaculates following vasectomy.

In some men, these sperm are present for many months or years meaning the men cannot be discharged from care or cease using contraception because it is not be certain if the surgery has been successful.

We have employed a fluorescent test that allows us to determine if these sperm are dead or alive in order to discriminate between failed vasectomy and inadequate clearance of dead sperm.

Finally, I am interested in occupational and environmental influences on semen quality. In collaboration with colleagues from the University of Manchester, I conducted a large multi-centre study of semen quality at 14 clinics within the UK, relating measures of semen quality to.

In 2008 we published the first paper describing how occupational exposure to glycol ethers (found in paints) was associated with a low motile sperm count. Further papers from this data are being prepared and will be published shortly.

Current Projects

  • Immediate and longer-term consequences for men who bank sperm prior to cancer treatment.
  • Trans-national reproduction: an exploratory study of UK residents who travel abroad for fertility treatment.
  • A pilot study to investigate the interaction between cytomegalovirus (CMV) infection and human spermatozoa.

Show: Featured publications All publications

Journal articles


Conference proceedings papers

  • Pacey AA (2016) Human reproduction keynote lecture - Modifiable and non-modifiable risk factors for poor sperm morphology. HUMAN REPRODUCTION, Vol. 31 (pp 1-1) RIS download Bibtex download

All publications


  • Pacey AA & Tomlinson MJ (2009) Sperm Banking: Theory and Practice. Cambridge University Press. RIS download Bibtex download

Journal articles


Conference proceedings papers

  • Idrees S, Fenwick M & Pacey A (2019) Examining the effect of nicotine on a mouse model of the ovarian reserve. HUMAN REPRODUCTION, Vol. 34 (pp 457-457) RIS download Bibtex download
  • Armstrong S, Bhide P, Arroll N, Cree L, Jordan V, Pacey A & Farquhar C (2017) Time-lapse Systems for ART - a systematic review. HUMAN REPRODUCTION, Vol. 32 (pp 225-226) RIS download Bibtex download
  • Pacey AA (2016) Human reproduction keynote lecture - Modifiable and non-modifiable risk factors for poor sperm morphology. HUMAN REPRODUCTION, Vol. 31 (pp 1-1) RIS download Bibtex download
  • Van Raemdonck LEM, Ata-ur-rehman , Davila-garcia ML, Mihaylova L, Harrison RF & Pacey A (2015) An algorithm for Morphological classification of motile human sperm. 2015 Sensor Data Fusion: Trends, Solutions, Applications (SDF), 6 October 2015 - 8 October 2015. View this article in WRRO RIS download Bibtex download
  • Zandieh Z, Ashrafi M, Mosaffa N, Sabbaghian M, Gilani MAS, Pacey A & Aflatoonian R (2015) Sperm DNA damage should be considered in infertile couples due to production of high inflammatory cytokines via toll-like receptors. HUMAN REPRODUCTION, Vol. 30 (pp 149-149) RIS download Bibtex download
  • Saeidi S, Shapouri F, Hoseinifar H, Sabbaghian M, Pacey A & Aflatoonian R (2012) Sperm protection by TLRs in the male reproductive tract. HUMAN REPRODUCTION, Vol. 27 RIS download Bibtex download
  • Pacey AA (2011) Male Infertility and Cancer. EUROPEAN JOURNAL OF CANCER, Vol. 47 (pp S37-S37) RIS download Bibtex download
  • Clarke HS, Callow A, Saxton D & Pacey AA (2011) Changes in sperm donor demographics in response to regulatory change. HUMAN REPRODUCTION, Vol. 26 (pp I145-I145) RIS download Bibtex download
  • Culley L, Hudson N, Blyth E, Norton W, Pacey A & Rapport F (2010) Travelling abroad for fertility treatment: an exploratory study of UK residents seeking cross-border care. HUMAN REPRODUCTION, Vol. 25 (pp I78-I78) RIS download Bibtex download
  • Iszatt N, Nieuwenhuijsen MJ, Bennett J, Povey A, Pacey A, Moore H, Cherry N & Toledano MB (2009) Trihalomethanes and Semen Quality in England and Wales. EPIDEMIOLOGY, Vol. 20(6) (pp S196-S196) RIS download Bibtex download
  • Pacey A (2009) Advances in male fertility preservation. EJC SUPPLEMENTS, Vol. 7(2) (pp 15-15) RIS download Bibtex download
  • Maddireddy V, Shariff U, Grady S, Gray L, Pacey AA & Rosario DJ (2007) Audit of an approach to post-vasectomy semen analysis (PVSA) - reliability, cost-effectiveness and feasibility of application to a nurse-led service.. BJU INTERNATIONAL, Vol. 99 (pp 38-38) RIS download Bibtex download
  • Shariff U, Maddireddy V, Grady S, Fletcher M, Pacey AA & Rosario DJ (2007) Fluorescent viability testing of human sperm - a novel technique to establish vasectomy success in early postvasectomy recanalisation. BJU INTERNATIONAL, Vol. 99 (pp 38-38) RIS download Bibtex download
  • Pacey A (2005) Sex drugs and y-front - Modern threats to male reproductive health?. CLINICA CHIMICA ACTA, Vol. 355 (pp S455-S455) RIS download Bibtex download
  • Tomsu M, Pacey AA, Li TC & Ledger WL (2002) Increased sperm DNA damage in partners of women with unexplained recurrent miscarriages: preliminary report.. FERTILITY AND STERILITY, Vol. 78(3) (pp S166-S166) RIS download Bibtex download


  • Pacey AA, Green RB, Gillies EA & Cannon RM (2005) Analysis Of Cell Morphology And Motility. Appl. 01 Sep 2005. RIS download Bibtex download
Research group

Current Collaborators

  • Lorraine Culley
  • Christine Eiser
  • Gary England
  • Adrian Eley
  • Eric Gillies
  • Richard Green
Teaching interests

I lecture in Phase 1b (GU and Endocrine) and Phase 3 (Women´s Health) of the Bachelor of Medicine and Bachelor of Surgery (MBChB) course. I also contribute to the Student Selected Components of Phase 1a (Critical Analysis) and Phase 1b (Research Methods) and offer B. Med. Sci., projects.

Outside the Medical School, I lecture on Module MBB 331 (Gametes and Embryos) in the Department of Molecular Biology and Biotechnology and also the APS 120 (Reproduction and Development) module in the Department of Animal and Plant Sciences.

I am also the Course Director and Admissions Tutor for the MSc in Science Communication which is starting in the Autumn of 2011.

Teaching activities
Media involvement

TV Programmes

Selected Radio Interviews

Recent Press Comments