Dr Laurence Shaw, deputy medical director of the Bridge Centre fertility clinic in London, sparked controversy last night following his claim that teenage girls who get pregnant are only obeying nature's law.
Speaking at the annual meeting of the European Society of Human Reproduction and Embryology (Eshre) in Prague, the leading doctor said females had been programmed by two million years of evolution to have babies in their late teens and early twenties, when fertility is at its peak.
Dr Shaw said: "Before we condemn our teenagers for having sex behind the bike sheds and becoming pregnant, we should remember that this is a natural response by these girls to their rising fertility levels.
"Society may 'tut tut' about them, but their actions are part of an evolutionary process that goes back nearly two million years; while their behaviour may not fit with western society's expectations, it is perhaps useful to consider it in a wider context."
However, religious and family groups in Scotland, which has western Europe's highest rate of teenage pregnancy, condemned his view.Teresa Smith, chair of the Scottish Christian People's Alliance, said the comments were "completely outrageous".
"Many things are an occurrence within nature but it does not mean they are the right thing to do," she said. "Girls of that age are not mature enough to bring up a baby. If they choose to have an abortion, there are long-term effects.
"Teenagers having sexual activity risk catching chlamydia and causing fertility problems. We should be promoting abstinence, not telling young people this is natural."
Tim Street, the chief executive, of the Family Planning Association Scotland, said the comments highlighted the need to educate teenagers about the dangers of sex.
"We have to actually explain to young people that we want them to wait until they are older before they start having sex and eventually kids.
"If, as he says, this is a natural, biological reaction to being who you are, we also have to explain that good policies on this are about delaying sexual intercourse until later on."
