In an ideal world they tell us, all parents would be teetotal, non-smoking, fit and healthy – and plan their pregnancies.

In reality this rarely happens;

You may not realise that you’re pregnant for some weeks.

You might be having problems conceiving.

You might be pregnant `by accident’.

Maybe you just want to know more about how babies are made.

This section deals with conception – how it happens and why it doesn’t – and some of the things you can do to give yourself a head start.