Plain English Summary
Background and study aims
Infertility is when a couple cannot get pregnant (conceive), despite having regular unprotected sex. The underlying cause of infertility is unclear in most men who suffer from the condition. The aim of this study is to find out whether male infertility can be caused by particular changes in DNA (the genetic material) and by unusual levels of reproductive hormones.
Who can participate?
Infertile men aged 18-65.
What does the study involve?
Participants are asked to complete a questionnaire and undergo blood sampling and clinical examination. A semen sample is also tested. Some participants have testicular biopsies (tissue samples from the testicles) as part of their treatment for infertility and a small amount of testicular tissue is stored. Participants are followed up over the telephone by a study investigator (clinician or nurse) on up to two occasions during the 3 years after the study.
What are the possible benefits and risks of participating?
The results of this study will advance the understanding of infertility in men, and may improve diagnostic methods and treatments for couples affected by infertility in the future. The results of the tests performed during this study could lead to incidental findings which are likely to require further medical assessment. In this case, participants are referred for the appropriate medical care that would be offered to an NHS patient. Some participants may experience pain or mild discomfort from giving a blood sample which involves inserting a needle into their arm to take blood. However, blood samples are collected by a trained member of the research team who is experienced in taking blood. All information and results from the study are kept strictly confidential and only used by researchers involved in the study.
Where is the study run from?
Imperial College Healthcare NHS Trust (UK)
When is the study starting and how long is it expected to run for?
July 2014 to July 2019
Who is funding the study?
Imperial College Trust (UK)
Who is the main contact?
Dr Channa N. Jayasena
Investigating the regulation of male fertility: an observational cohort study
The study aims to identify factors that may be causing male infertility. These factors will provide better understanding of male infertility and its underlying pathophysiology.
West London Research & Gene Therapy Advisory Committee, 15/07/2014, ref: 14/LO/1038
Observational cohort study.
Primary study design
Secondary study design
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
Patients will be recruited via the Andrology department at Hammersmith Hospital, London. The aim is to recruit approximately 2000 men. Participants will be asked to complete a questionnaire, undergo blood sampling and clinical examination. A semen sample will also be analysed. Some participants have testicular biopsies as part of their treatment for infertility and a small amount of testicular tissue will be stored. Data will be processed statistically and used to highlight the key mechanisms underlying male infertility. Participants will be followed up over the telephone by a study investigator (clinician or nurse), on up to two occasions during the 3 years following study recruitment.
Primary outcome measure
Genetic/molecular abnormalities, assessed using state-of-the-art techniques at the time including Sanger sequencing, next generation sequencing, array comparative genomic hybridisation (CGH), polymerase chain reaction (PCR) and enzyme assays and/or immunoassays, at baseline
Secondary outcome measures
1. Sperm parameters, measured using routine semen analysis at baseline
2. Smoking status, measured using a questionnaire at baseline
3. Weight, measured using scales at baseline
4. Sperm count abnormalities, measured using routine semen analysis at baseline
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Infertile men
2. 18-65 years of age
Target number of participants
Participant exclusion criteria
1. History of anaemia
2. Needle phobia
3. Impaired ability to provide full consent to take part in the study
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Imperial College Healthcare NHS Trust
Imperial College Trust (ref: P52570)
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
The planned publication date is approximately one year after the trial end date (2020) in a high-impact peer reviewed journal.
IPD sharing plans
The current data sharing plans for the current study are unknown and will be made available at a later date.
Intention to publish date
Participant level data
To be made available at a later date
Basic results (scientific)