Teaching unions have criticised a “politically motivated” review of the way sex education is taught in schools, after Conservative MPs voiced concern that children were being exposed to “graphic” material including “lessons on oral sex”. Rishi Sunak has asked the Department for Education to “ensure schools are not teaching inappropriate or contested content” in the subject of relationships, sex and health education (RSHE), and will bring forward the review that was already “on the cards for some time”. Sunak confirmed the review, which will apply only to state schools in England, after a Tory MP, Miriam Cates, said children were being exposed to sex education classes that were “age-inappropriate, extreme, sexualising and inaccurate”. The prime minister and the education secretary, Gillian Keegan, are understood to be concerned about the issues raised and will consider whether schools should place clearer limits on the content taught to children, depending on their age. Posing a question to Sunak during prime minister’s questions, Cates said: “Graphic lessons on oral sex, how to choke your partner safely, and 72 genders. This is what passes for relationships and sex education in British schools. “Across the country, children are being subjected to lessons that are age-inappropriate, extreme, sexualising and inaccurate, often using resources from unregulated organisations that are actively campaigning to undermine parents. “This is not a victory for equality – it is a catastrophe for childhood.” Sunak responded: “Our priority should always be the safety and wellbeing of children, and schools should also make curriculum content and materials available to parents. “As a result of all of this, we are bringing forward a review of RSHE statutory guidance and we will start our consultation as soon as possible.” Before PMQs, Cates coordinated a letter to the prime minister that was signed by MPs including Priti Patel, former levelling up secretary Simon Clarke, Jonathan Gullis and Andrea Jenkyns, urging Sunak to launch an independent inquiry into what young children have been asked in lessons concerning how they “feel” about oral and anal sex. The joint letter warned that “even primary schoolchildren are being indoctrinated with radial and unevidenced ideologies about sex and gender”. Geoff Barton, the general secretary of the Association of School and College Leaders and a former headteacher, said: “The vast majority of schools are incredibly cautious and sensible about the teaching of RSE and we disagree with the sweeping generalisation and inflammatory rhetoric from Miriam Cates in the Commons. “Schools are doing their best to teach children and young people about things like being safe and respectful relationships in a sensitive and age-appropriate manner, but they are constantly subjected to unhelpful potshots from various individuals and groups. “We welcome the review of relationships and sex education as part of an ongoing process of ensuring that schools and teachers are well supported in delivering this topic, but our understanding is that this review has been on the cards for some time, as one would expect, given that this is a relatively new and very important part of the curriculum.” James Bowen, director of policy for the National Association of Head Teachers, said: “It is hard to be anything other than deeply concerned by this announcement. “The overwhelming majority of schools are doing nothing more than following the government’s own statutory guidance when it comes to relationships and sex education. It is worth remembering that the current curriculum was subject to extensive consultation before it was introduced. “We have seen no evidence to suggest there is a widespread problem with pupils being presented with age-inappropriate materials, and if this were the situation, we would expect it to have been picked up on a case-by-case basis. “There is a real concern that this is a politically motivated review, rather than one based on the reality of what is happening in the vast majority of schools up and down the country.”