The first vaccine to prevent cervical cancer was recently approved for use in the European Union (Gardasil^®, Merck &Co, Inc.)[1]. This brings closer the possibility of routine vaccination against human papillomavirus (HPV) to prevent pre-cancerous cervical lesions and invasive disease [2]. This quadrivalent vaccine, which is highly effective against HPV types 6/11 (low risk) and HPV types 16/18 (high risk), could have a significant public health impact in reducing HPV prevalence, persistent HPV infection, cervical neoplasia and genital warts [3]. A bivalent vaccine (Cervarix^® GlaxoSmithKline) with similar levels of protective efficacy against HPV types 16/18 is expected to be licensed in 2007 [4]. The United States Centers for Diseases Control has already recommended routine vaccination of Gardasil^® for 11 and 12 year old girls, and 9–10 year olds at the discretion of their physician [5]. (Pre)-adolescents are the main target group as the vaccine is prophylactic and will be most effective if administered prior to sexual initiation [6]. The public health impact will be greatest if a high coverage of the target population is achieved [7]. School vaccination programmes would be feasible in the UK but acceptability by the public of routine vaccination against a sexually transmitted infection (STI) is still uncertain and parental consent for vaccination would be necessary.

A number of studies of parental attitudes – mostly conducted in the US – suggest a considerable interest in adolescent HPV vaccination, with most parents in favour of protecting their children [8]. We previously reported a population-based survey in Manchester, UK, that assessed the acceptability of HPV vaccines to parents of 11–12 year old school children [9]. The study included parents from a wide range of backgrounds, and 81% replied that they would consent to HPV vaccination for their child, although only 38% were definite in this view. Long-term safety of the vaccine was an important issue, and a minority of parents would refuse on grounds that vaccination could encourage early sexual debut or riskier sexual behaviour. In view of the fact that, in the UK, at least 25% of adolescents will have their first experience of sexual intercourse before the age of 16 [10], and to ensure a high population coverage, it may be necessary for HPV vaccines to be available for under-16s without parental consent [11]. In the UK, vaccines could be given in general practice, at sexual health clinics, or within targeted "catch-up" programmes for women up to 26 years.

Consent for treatment is based on the ethical principle of patient autonomy, a concept that has many definitions [11, 12] but is associated with the right to privacy and confidentiality, acting according to one's own volition, self-mastery, choosing one's own moral responsibility and accepting responsibilities for one's choice. Consent is valid if it is voluntary and the individual is both informed and competent [13]. In the face of increased sexual and reproductive health care needs of adolescents, many countries have enacted "health services to minors" legal Acts, lending support to a notion of "adolescent autonomy" [14]. In England the Law Lords ruled in 1985 that a girl under 16 could consent for contraception if able to understand the proposed treatment and it implications [15]. Subsequently, the Fraser ruling provided guidance for health workers on assessing the maturity and competency of a minor to comprehend the information given [16]. As HPV is sexually transmitted, it would be logical to make HPV vaccination routinely available to sexually active minors whose parents had refused consent. This could, however, stigmatise HPV vaccination and make it more contentious, as some parents are opposed to confidential sexual health services for minors [17]. To explore this issue our survey included two items, the first asking if parents would approve a well-informed child being allowed to access the vaccine at a sexual health clinic without parental consent, and the second to explain in their own words the reason for their answer. In this paper we report a semi-qualitative analysis of their responses, using an ethical framework to explore parents' views on HPV vaccination in the context of adolescent autonomy.

In the UK there is a high teenage pregnancy rate and an epidemic of STIs [19]. The high and increasing prevalence of HPV [20] among young women is probably due to high-risk behaviour and biological immaturity of young adolescents exposed to infection [21]. The government's sexual health strategy promotes expansion of sexual health services and a determined effort to make these accessible to under-16s [22], often through avenues outside the clinical setting [23]. If projections about parental acceptability of vaccination are correct, it can be anticipated that, if parental consent is mandatory, at least 20% of under-16s will not be vaccinated against HPV. Strategic decisions will be needed on whether to try and optimise coverage by making the vaccine available without parental consent, and whether this would provoke negative reactions from parents.

In trying to answer these questions, it becomes obvious how little research (as opposed to media coverage) has been conducted, either in UK or elsewhere, on the acceptability to adults of policies allowing under-16s to be treated without parental consent [24–26]. Our research indicates strong, but divided, views on medical intervention without parental consent as well as confusion about the legal framework governing parental responsibility. Parents with favourable views referred spontaneously to children's ability to understand and process information, although it remains unclear precisely how they interpreted "well-informed". They argued from an ethical perspective in support of adolescent autonomy as a developmental, age-independent process of separation and detachment from the family [12] and this is consistent with allowing a competent adolescent to access confidential sexual health care. In reality, the right to treatment is still mediated by an adult, but it is a health professional instead of the parent. This role is approved by parents who argue that this protects vulnerable adolescents, but is challenged by other parents who question whether health professionals can judge what is in a child's best interests. Their views corresponded to a more recent definition of autonomy that emphasises maintaining "family connectedness" [12]. Largely based on US studies, family support is considered to encourage healthy development and to result in fewer risky behaviours [27–29] but is inconsistent with the principles of confidential adolescent sexual health provision. This is not to say that parents who want to be involved in health decisions would stand in the way of appropriate preventive or treatment strategies such as HPV vaccination, but that they want to be involved in the decision. We previously reported that 74% of parents intended to make a joint decision about HPV vaccination with their child and this was associated with support for the vaccine [9]. In the current analysis, we further demonstrate that some parents saw no need for the vaccine to be available at sexual health clinics if it could be provided in schools. For this reason, in the UK, a high HPV vaccine coverage may be achievable through a school-based strategy, as it was for adolescent hepatitis B vaccination [30], because parental consent will be sought.

The ethical question remains, however, of the right of adolescents to request the vaccine if, as minors, they subsequently become sexually active without their parent's knowledge and their parents earlier had declined consent. As the principle of adolescent autonomy is legally recognised in the UK, logically it should include the right to HPV vaccination [31]. In the Gillick case, the Law Lords focused on the issue of consent rather than a notion of parental rights or powers. In fact the courts held the view that parental rights did not exist, other than to safeguard the best interests of the minor [32]. One scenario would be to argue that HPV vaccination is different from other sexual health interventions because effective cervical screening programmes provide a safety net for adolescents who subsequently develop cervical intraepithelial lesions. This argument could not be applied with respect to genital warts if a quadrivalent vaccine was in use. This is an important consideration because in 2001 there were 32,185 diagnoses of genital warts in females, 29% of which were in those under 20 years of age [33]. Another approach would be to vaccinate under-16s without parental consent within a catch-up programme that was accessible to this age group. Catch-up programmes are expensive and it is not clear whether vaccination will benefit women already exposed to HPV [3] but they are quite likely to be adopted as an interim measure. It would be important to ensure that adolescents were aware of catch-up programmes as those who have not been vaccinated may feel anxious if most of their peers received the vaccine.

There are a number of limitations to this study, notably with the use of semi-qualitative data taken from surveys [18], which is intended to provide insights not conveyed by the quantitative data. Being partly quantitative, biases in the survey could be reflected in the analysis, and with a relatively low response rate, the results cannot be assumed to represent all parents' views. A greater limitation is that semi-qualitative data are not detailed and do not provide the more informative type of data that can be gained from in-depth qualitative approaches. Nevertheless, our study provides some insights into the need for policy makers to engage more effectively with parents on sexual health matters. Parents rejecting the principle of adolescent autonomy were more opposed to adolescent HPV vaccination per se. For adolescents, access to health care is always mediated by gate keepers such as parents, health providers and communities and it is vital not to undermine efforts to make it easier for them to obtain the health care they require. A public debate is needed to allow all perspectives to be considered and to help parents and policy makers to understand the ethical issues that underpin adolescent autonomy, confidentiality and privacy [34], as well as the skills required to talk to children and promote adolescent self-regulation [35]. The doctor-patient relationship is the primary focus of ethics in medicine, and clinicians must be prepared to discuss these issues with adolescents and their parents [36].

Although recognising its benefits, some parents might disapprove of HPV vaccination without parental consent. This could pose a dilemma in countries where adolescent sexual autonomy is legally recognised and might contribute to the view that the vaccine encourages sexual promiscuity. Such concerns would need to be openly addressed to avoid misunderstanding that the purpose of vaccination is prevention of cervical cancer.