Such a trial should not limit the choices of women who already have a preference

The crucial question is: What would be the purpose of a randomised controlled study of home versus hospital birth? It could be argued that more information about the outcomes associated with home birth would increase the opportunity for women to make informed choices about their care. However, the questions that women and their partners have about home birth centre on issues of safety and how to arrange a home birth in the face of opposition. While they would be interested to hear about breast feeding and psychological outcomes, those who are doubtful are concerned about the risks and those who are keen to have a home birth tend to believe already that it would be a positive experience for themselves and their family.

A trial could be designing the study in such a way as to minimise the effect of intervening variables or compare home versus hospital births as currently experienced. Factors such as continuity of carer, women's control, privacy, hours of (supportive) contact with a midwife, and midwives' experience and attitudes are probably not the same at home and in hospital, and these variables are likely to have an independent effect on women's experiences and the incidence of breast feeding.

If a trial is to be carried out we believe it would be important to undertake a preference trial, given that consideration of the putative benefits and side effects of home versus hospital birth point towards effective rather than absolute equipoise,1 and some women have a clear preference for one or other treatment. Thus, potential recruits would be invited to choose treatment A (home) or B (hospital) or agree to be randomly allocated a treatment.1 We note that all four women who were allocated home birth in the pilot study of Dowswell and colleagues were pleased, whereas four of the six allocated delivery in hospital were disappointed. It is not clear when they said this, and we wonder whether they thought it was a true option during pregnancy to ask for a home birth. As they were all multiparous women of low obstetric risk, they should all have been offered this choice.

Prejudice against home birth or lack of confidence among midwives and doctors could seriously jeopardise successful recruitment and treatment as intended, even in a preference trial. For this reason, we suggest any trial should be conducted in an area that already has a higher than average rate of home births. However, our main concern is ensuring access to home birth for all women who want it. No trial should be conducted at the expense of limiting choice among women who have a preference, given that there is no evidence to suggest that all births should take place in hospital.2

We think that resources would be better spent evaluating patterns of midwifery care specifically aimed at providing continuity of carer, choice of place of birth, and empowerment in hospital and at home.3 There is currently a gap between what is known to be effective and what is provided. For example, there are well documented ways of supporting women who wish to breast feed,4 5 but in the United Kingdom only two maternity units fully meet Unicef's baby friendly criteria.6