Giving contraceptive implants to underage girls in school clinics could encourage them to have unprotected sex, an MP claims.

Veteran Tory Sir Roger Gale says he was “astonished” to learn the device is being inserted into the arms of 15-year-olds across the Canterbury district, without their parents’ consent.

He claims that because the implant is 99% effective against pregnancy, girls fitted with one are more likely to have sex without a condom, exposing them to a higher risk of contracting sexually transmitted infections (STIs).

The implant – comprising a small plastic rod placed under the skin – is being inserted by nurses and doctors from the Kent Community Health Trust.

It releases progestogen into the bloodstream to prevent pregnancy and is effective for three years, but offers no protection against STIs.

School clinics are run at Canterbury High, Spires Academy, Community College Whitstable, Herne Bay High School and The Abbey School in Faversham.

Sir Roger, 74, said: “I find it quite astonishing, because aside from everything else, the implant doesn’t offer any protection against diseases.

“If you give a child a condom, they are afforded a degree of protection.

“If you’re going to offer anything at all, surely you should offer something that offers effective protection, rather than something that encourages people to engage in unprotected sex?

“You’re placing young women at risk of chlamydia, and all sorts.

“I have never personally been in favour of providing contraception to children, and particularly underage children without parental consent.

“I understand that young people engage in activities that may place them at risk, but there is a level of parental respect that should be exercised.”

But Dr Mark Lawton, chairman of the British Association for Sexual Health and HIV Media Group, has highlighted the benefits of implants.

“We wholeheartedly support the provision of contraception in schools, the availability of which has played a significant part in the record fall in under-18 pregnancies in Kent in recent years,” he said.

“The implant represents arguably the most effective form of long-acting reversible contraception available.

“In the vast majority of cases it is simple to fit and remove and it also does not stop ovulation, meaning an individual’s physiology is less disrupted compared to injection or pill-based contraceptive methods, while having the added benefit of being less prone to failure as you don’t have to remember to take it, unlike the pill for instance.

“Sexual health staff are highly trained and a risk assessment would always be carried out by staff when discussing contraception needs with young people, to help identify anyone at risk of abuse, and to fully explain the law in respect of underage sex.

“We would urge anyone who is sexually active to use a condom and to visit their local sexual health service for regular and confidential check-ups and testing.”

Hilary Pannack, chief executive of teen parenthood charity Straight Talking, also supports the use of implants.

“Teenagers will have sex whether we encourage them not to or otherwise,” she said.

“We need to make sure that if they’re going to do that, they’re going to be safe, because teenage pregnancy is a long-term issue that’s going to impact on their life and a child’s life significantly.

“We need to give women and girls choice in the types of contraception, as it’s going to affect their bodies.”