ONE LAW FOR CONCEPTUS, ONE FOR ABORTUS

231 MALE INFERTILITY AND IN-VITRO FERTILISATION

ETHICAL VIEWS ON RESEARCH ON HUMAN EMBRYOS HELD BY FIRST YEAR MEDICAL STUDENTS WHO FOUND IVF ITSELF ETHICAL

SIR,-The report by Dr Cohen and colleagues (June 2, p 1239) on the successful treatment of male infertility by in-vitro fertilisation (IVF) in 34% of cases, the rate per cycle being 23%, is encouraging but leaves important questions to answer. Cohen et al indicate that the success of treatment depends on the method of semen collection and purification, but do not describe what they did. Nor do they say whether any cases was excluded in which preliminary investigations on semen

purification suggested unsuitability. Perhaps

none was

excluded as some successes were described despite only a few weakly motile spermatozoa being obtained. On the other hand, the outcome in those cases is not described although inherent sperm defects may result in early embryonic loss rather than failure of fertilisation. A fundamental question concerns the diagnosis of male infertility (or fertility) from standard seminal analysis. Cohen and colleagues use counts of sperm density, motility, and morphology well below the usual norms as criteria for abnormality. However, there remains great uncertainty about the interpretation of seminal analysis. Low counts do not preclude a good chance of natural conception, and semen with high counts may be ineffective. Sperm transport and fertilising ability are separate but usually related key factors. Heterologous studies using hamster eggs indicate defective fertilising ability in one-third of couples with unexplained infertility including those with normal findings on standard seminal analysis. This has now been associated with failure to penetrate the partner’s cervical mucus in vitro,2 and our

study on human IVF and in-vivo mucus penetration (by the postcoital test, PCT) has confirmed the association.3Thus sperm motility to achieve both transport and egg penetration is linked, and failure of sperm/mucus penetration is mostly due to a defect residing own

in the sperm, not in the mucus or eggs. In routine clinical practice we have shown that the PCT provides the best indication of prognosis for natural conception, both when seminal analysis is normal4 and abnormal (unpublished). The chance of conception with a positive PCT (indicated by adequate forward-progressing spermatozoa about 12 h after intercourse) is

findings of seminal analysis. Without testing sperm/mucus penetration male infertility cannot be properly assessed, nor can the benefit of IVF be properly evaluated. If severe oligoastheno-teratospermia can really be overcome reliably by IVF, even when associated with failure of sperm/mucus penetration, it would represent a major, and indeed the only, advance in treatment for what seems at present the worst problem in infertility practice. We look forward to the full details of Cohen and colleagues’ study in due course.

equally good,

whatever the

University Department of Obstetrics and Gynaecology, Bristol Maternity Hospital, Bristol BS28SG

M. G. R. HULL CATHRYN M. A. GLAZENER

1 Aitken RJ, Best FSM, Richardson DW, et al. An analysis of sperm function in cases of unexplained infertility: Conventional criteria, movement characteristics, and fertilizing capacity. Fertil Steril 1982; 38: 212-21. 2 Schats R, Aitken RJ, Templeton AA, Djahanbakhch O. The role of mucus-semen interaction in infertility of unknown aetiology. Br J Obstet Gynaecol 1984; 91: 371-76. 3 Hull MGR,

Joyce DN, McLeod FN, Ray BD, McDermott A. Human in-vitro fertilisation, in-vivo sperm penetration of cervical mucus (the postcoital test), and unexplained infertility Lancet (in press) MGR, Savage PE, Bromham DR. Prognostic value of the postcoital test: Prospective study based on time-specific conception rates. Br J Obstet Gynaecol

4 Hull

1982; 89: 299-3O

ETHICS OF RESEARCH ON EMBRYOS

SIR,-We found Dr Templeton and colleagues’ letter (May 12, p 1081) interesting in that it supports the general scientific view that research on in vitro fertilisation (IVF) is justified. 1-5 It is heartening to know that 65% of women undergoing sterilisation support such research. In 1981 we were considering setting up an IVF and embryo transfer programme and did a questionnaire survey of 113 patients attending our subfertility clinic and 168 first-year medical students.

Most respondents considered IVF to be ethical (73 - 5% of the subfertile patients and 78 - 8% of the students). The students who

thought IVF ethical were asked whether it was ethical to extend the procedure to research on human embryos. They were equally divided on this point (see table). In such a heterogeneous Asian society as Singapore, such results are interesting. However, medical representative group.

Department of Obstetrics and Gynecology, National University of Singapore, Kadang Kerbau Hospital, Singapore 0821

students may

not

be

a

NG SOON CHYE S. S. RATNAM

3.

Report from Council for Science and Society. Lancet 1984, i: 1290. embryo transfer. Recommendations to European Medical Research Councils. Lancet 1983; ii: 1187. American Fertility Society. Ethical statement on in vitro fertilisation Fertil Steril 1984;

4.

Royal College

1.

2 Human in-vitro fertilisation and

41: 12.

Committee 5.

Royal Society.

of Obstetricians and Gynaecologists. Report of the RCOG Ethics fertilisation and embryo transfer. London: RCOG, 1983. Human fertilisation and embryology. London: Royal Society, 1983

on in vitro

ONE LAW FOR

CONCEPTUS, ONE FOR ABORTUS

SIR,-With the publication of the Warnock report has come the recommendation that experimentation on the human conceptus should be limited by statute to the first 14 days of life. This time has been chosen, because earlier the rudimentary neural tissue of the primitive streak will not have developed. A minority report suggests that up to 40 days of experimentation could be accepted since, until then, the sensory apparatus to allow the possible appreciation of pain has not developed. The BBC 2 television programme Brass Tacks debated the Warnock report under the title Tomorrow’s Child. Doctors, scientists, and philosophers discussed, very seriously, the arguments for and against the limitation of research on embryos to 14 days. No-one suggested that experiments should continue beyond 40 days, when the conceptus might be able to perceive pain, as this was considered generally unacceptable. The Abortion Act currently allows a pregnancy to be legally terminated up to the 28th week, although improved neonatal intensive care techniques have made most doctors slow to induce abortion after 24 weeks’ gestation. Although I accept neither abortion nor experimentation on "spare embryos" as ethically tolerable, I find arguments against early experimentation on the human conceptus, by people who would accept abortion of the same conceptus at a much later gestation, highly disturbing. The value of an embryo and the consequent assignment of its rights seems to depend on whether its parents have abortion or fertility in view. Clarendon Wing, General Infirmary at Leeds, Leeds LS29NS

BRIAN S. MOLLOY

EPIDURAL CLONIDINE PRODUCES ANALGESIA

SiR,—In animals, a-adrenergic agents can exert an antinociceptive effect not only through actions on noradrenaline sensitive supraspinal sites 1,2 but also through a direct action on the spinal cord.3 The spinal cord effect can be reversed by a-adrenergic blocking agents, but not by naloxone, thus suggesting that a specific a-adrenergic receptor is responsible. Yaksh et al have shown that