In its first debate on abortion for 16 years, the British Medical Association voted by three to one yesterday to throw out a proposal that the legal time limit should be lowered to reflect advances in medical care.

Growing expertise in neonatal units has seen increasing survival rates for babies born at 24 weeks or less, although many have lasting disabilities.

Demands for a reduction in the legal limit have also been fuelled by 3-D pictures of foetuses in the womb, in which they appear to smile, grimace and "walk". Medical and lay opinion has since grown in favour of reducing the legal limit.

But representatives at the BMA's annual meeting in Manchester argued that although late abortions performed after 20 weeks were often distressing, they were necessary if a pregnancy was discovered late or severe abnormalities were detected in the baby.

Less than 1 per cent of the 180,000 abortions a year in England and Wales are performed at more than 22 weeks and 87 per cent are carried out before 13 weeks.

John McQueen, a consultant obstetrician from Bromley, who proposed the motion calling for a lowering of the limit, said that, in the past, babies born at 28 weeks had simply died. Now those as young as 23 weeks were surviving, though many were disabled. "Ventilation has become standard, which was the first thing to improve the care of babies. The use of steroids in premature labour has also helped enormously," he said.

Defending the 24-week limit, Jan Wise, a psychiatrist, said it would be shameful if the BMA voted to lower it. He pointed out that few abortions were carried out after 20 weeks – often because of difficulties accessing services. More than one in 10 primary care trusts had waits of five to eight weeks, he claimed.

"This isn't a cosmetic procedure you can sit around and wait for," Dr Wise said. "This [waiting time] is disgusting. There is a lot of anguish in deciding to have such a termination."