Many modern women it seems, are too fulfilled, educationally, professionally and financially to give it all up for a baby early on. Another way of looking at it is that they feel insecure at the thought of getting back on the career ladder after time out on maternity leave.
There are also a growing number of middle aged divorcees stepping back in the ring for 'pregnancy round two' with a new partner.
That said, 25-29 is the most common 'birthing' age. And while teenage pregnancies have dipped overall, the kids are still doing their bit for national birth statistics by popping them out young and unplanned like rounds from a faulty machine gun.