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Prof John Guillebaud
Prof John Guillebaud profile picture
  • Emeritus Professor of Family Planning and Reproductive Health
  • Maternal & Fetal Medicine
  • UCL EGA Institute for Womens Health
  • Faculty of Pop Health Sciences

John Guillebaud  – pronounced

in 2 syllables “Gil-boe”[a Huguenot name]

Emeritus Professor of Family Planning and Reproductive Health, University

College London (he was the first clinical professor in the world with this

John Guillebaud was born at Buye, Burundi, brought up in Rwanda, Uganda and
Kenya, and continues to make regular training and support visits for

healthcare professions in Africa (Central and South).

Ex-Medical Director, Margaret Pyke Centre for Study and Training in Family
Planning, he is a vasectomy surgeon and Research Director based at the Elliot-Smith
Clinic, Churchill Hospital, Oxford, where he is involved in studies of the
world’s first non-hormonal ‘dry orgasm’-inducing male pill.  

He is author/co-author of c 300 publications on environmental sustainability,
birth control for women and for men, reproductive health and population and of
seven books, which are available in 10 languages including Chinese and
Japanese. Updated editions (2008 or 2009) are available of “Contraception:
Your Questions Answered”, “Contraception Today”, the “Oxford Handbook of
Reproductive Medicine and Family Planning” and “The Pill – the Facts”. He
also consults as requested on an ad hoc basis both internationally (eg
WHO) and nationally (eg Department for International Development).  

While still a 2nd year med student he attended a
lecture on human population and the future, given by the
Biologist Colin Bertram. This talk launched his concern for global environment
issues and established the direction of his career, recognizing that
contraceptives are just as much icons for the environment as was/is his
Brompton cycle. 

This choice of contraception for both genders as his specialty and
life’s work, necessitating higher degrees in both
surgery and gynaecology, was ultimately driven by fear
that humankind, through ever increasing consumption and pollution per
person multiplied by the increasing number of persons, would put this
uniquely life-sustaining but finite planet in jeopardy.   He

the originator of the Environment Time Capsule Project (1994-2044) as
described atwww.ecotimecapsule.com,

Chair of www.peopleandplanet.net,  

Vice-Chair of www.Populationandsustainability.org

and a Patron of www.populationmatters.org 


Research Themes
Research Summary

Interest in research re all forms of contraception, population and environment

Research ongoing with Dr Nnaemeka Amobi into a novel male systemic method of contraception.

 The "dry orgasm" pill.

This is a novel non-hormonal approach

based on the same highly unusual side effect of two drugs with quite different

main actions – and first reported many decades ago. As far back as 1961, American

psychiatrists were reporting the side effect, succinctly put in the title of a

1968 case report about this particular phenothiazine:  "Thioridazine-induced inhibition of

masturbatory ejaculation in an adolescent". The inhibition was of the semen being delivered, NOT of the rhythmic contractions and sensations of normal male orgasm.

Later– acting on reports going back even further to the mid 1950s – workers in Israel

published [Homonnai et al Contraception 1984;29:479-91] a pilot study in 13 men

of the identical strange effect of an alpha-adrenergic blocker, under the title

"Phenoxybenzamine – an effective male contraceptive pill". This title

was not perhaps an overstatement, since at no time did any of the volunteers

produce any semen at all at ejaculation, while on treatment with 10-30 mg of

the drug, yet with apparently complete restoration of semen volume and quality

on discontinuation. There was no evidence of retrograde ejaculation nor of

effects on testosterone, FSH, LH or prolactin. Of greatest interest is that the men remained very happy with their sex lives:  none of the men reported any adverse effects on libido, erection, sexual

performance or on their sensations of orgasm and ejaculation - despite no fluid


Where has this interesting possibility got to, in the 24 years since that pilot

study? The original drugs had too many reported side effects, indeed

thioridazine is no longer in the British National Formulary and

phenoxybenzamine has a very restricted use as a hypotensive in the treatment

phaeochromocytoma. But the pharmacologists Amobi and Smith at King's College

Hospital have continued working systematically on our excised vasectomy specimens from  the Margaret Pyke (University College London) and Elliot-Smith (Oxford)

clinics, and have identified the mechanism of action (on the vas and also,

necessarily to result in dry ejaculations', downstream' from the

prostate).  The original drugs, some new

ones they have identified and also tailored ones that have been synthesised

with the same 'chemical signature', all if given at the right (low) dosage

contrive to paralyse the longitudinal muscles of the Wolffian duct system while

still permitting the circular muscles to contract. This leads to loss of the

usual co-ordinated ejaculatory "Mexican wave", instead there is a

sphincter action, reversibly preventing emission of both sperm and seminal


At the time of writing we are seeking funding to take the most promising candidate

drugs forward through all the required preliminary Phases of clinical testing

for efficacy and safety. This will certainly cost millions of dollars and take

at least 10 more years – 60 years since those first reports. 

Teaching Summary
Presentations by invitation for 1 to3 1/2  hours on Contraception anywhere in UK, sometimes abroad. Audiences mainly general practitioners and Practice Nurses.

Details from: 
palmtraining.org.uk OR
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