You can be too old to be a parent. If you won't be able to play with or care for your child and don't have a spouse or alternative child rearer who can, then for the greater good of the child you should forsake your desire. But if you can ensure that your child will be cared for, then age matters less. Yes, an old mother will probably die before her child is properly an adult. But my mother died when she was 50, I was 20 and I don't wish I hadn't been born.

· Noreena Hertz is an academic

Sarfraz Manzoor

The right time to have a baby is when it is in the best interests of parents and child. Too young and parents might feel financially and emotionally overwhelmed; too old and they may be claiming pension and child benefit at the same time. In practice, people have children for selfish reasons: to underline the depth of their relationship, to fill an emotional need, to ward off mortality. I think 63 is too old to be a mother but we have double standards. Older fathers are applauded for their virility.

· Sarfraz Manzoor is a writer and broadcaster

Karol Sikora

Biologically, women are not made to conceive after the menopause. And biology is after all common sense - it's part of our evolutionary heritage. What child wants a 70-year-old mother turning up to their primary school? Teenagers, with their own problems, will have an apparent great-grandmother to explain. And what a waste of medical resources at all stages. Having a baby is a gift - not a right that medical science can achieve at a cost. And there are enough children born in the world. For the sake of the world's children, let's stop this nonsense.

· Karol Sikora is a cancer specialist