Patients have been warned against cosmetic surgery "holidays" from unethical clinics abroad, after research showed the number of people suffering complications on their return home has increased in the past 18 months.

The British Association of Aesthetic Plastic Surgeons (Baaps), which represents one in three plastic surgeons, said a quarter of its members in a poll reported a rise in patients complaining of complications after surgery abroad. One surgeon said he had seen more than 16 cases – almost one a month – from cosmetic surgery tourism.

The research, published during the association's three-day annual conference in Cardiff, also reported "appalling and unethical" marketing tactics by websites offering packages overseas. It found that:

• 90% of those surveyed did not mention the risks or possible complications from surgery.

• More than half only offered online or telephone consultations prior to surgery.

• 39% did not include details of the procedures.

The top five countries from which surgeons reported seeing patients return with problems were South Africa, Poland, Belgium, Turkey and Thailand.

Other figures presented at the conference revealed Britain's growing enthusiasm for cosmetic surgery. The number of gynecomastia operations – often referred to as "man boob" reductions – have soared by 1,000% in the past five years, fuelled by middle-aged and elderly men wanting to bare their chests on holiday. Baaps said that from a very low level of 22 such operations among its members in 2003, the total had jumped to 323 in 2008.

One of the most common procedures for UK patients to have abroad is a "tummy tuck", it said, but it is also one of the operations with a high risk – one in five patients suffer post-operative problems such as wounds not healing. Another common operation is breast augmentation, which carries a 10% risk of problems, such as scarring or loss of sensation.

Nigel Mercer, a consultant plastic surgeon and president of Baaps, said: "There's no doubt we are seeing more problems because more people are having cosmetic surgery. The number of firms set up to organise packages is also increasing." Research into websites had shown there were many unethical practitioners who did not warn would-be patients about possible complications.

He said his main concern was patients receiving poor post-operative care. One patient who had a tummy tuck operation experienced fluid dripping from his abdomen on to the floor of the plane on his way home, Mercer said.

The other professional body governing plastic surgeons, the British Association of Plastic, Reconstructive and Aesthetic Surgeons, has urged the NHS to treat patients suffering complications from surgery abroad only when they are in severe pain or have life-threatening conditions.

Douglas McGeorge, a past president of Baaps, said people had to be aware of the risks and costs of surgery abroad. He said: "There are some very good surgeons abroad. What we have in this country is a system that is much more regulated than in Europe. Patients have to be able to know what they are getting for their money, and the qualifications of their surgeon." The cost of revision surgery was often "significantly higher" than the original surgery, he said.

Mark Bury, chief executive officer of SurgiCare, one of the largest cosmetic surgery networks, said he had seen a surge in popularity for surgery abroad, but also a "huge increase in very unhappy people calling us, desperate to fix the mistakes cowboy surgeons abroad have made". He added: "You get what you pay for and although going abroad for surgery can sometimes appear cheaper, access to important after-care solutions will not be available to the patient once they are back in the UK, and if something does go wrong when they are home, the patient will have to pay again for any corrective procedures."

McGeorge said the growing trend for "man boob" reductions was mostly middle-aged and elderly men, but that teenage boys were also having the operation.

"I get people coming to me in their 50s and 60s. Men who have never taken their T-shirts off in public before," he said. ENDS