Baby is a big test for Samantha Cameron

Happy news for the Camerons as Sam Cam announces that she is pregnant again. This is especially felicitous following the death of their son Ivan last year. If the Tories win the election, it will be the second Downing Street birth since Cherie Blair had Leo 10 years ago.

But is it all quite so rosy? Political cynics will claim that this is some sort of devious Conservative ploy to attract voters while tut-tutters among the medical commentators will claim that she is surely too old to be having another baby, especially given the possibility that their working lives may suddenly get very busy indeed.

These are mistaken views. Thirty-eight is not old these days, and this new pregnancy will simply place her among many other modern career women who juggle work and family. It's nothing new, and not impossible.

As for a piece of political spin I think it is highly unlikely for the following reason: to get pregnant again, having had one severely disabled child and watched it die, is a brave and difficult thing to do. It will make the already strenuous process of having a baby all the more angst-ridden, and for many women pregnancy can be a nightmare of anxious waiting, scans and worry, because, of course, assurances that the new baby will not be born disabled cannot be given. Sarah and Gordon Brown will have experienced it following the arrival of baby John, two years after they lost their daughter.

Many people would imagine that a new birth following a tragic death is the ultimate panacea, and that the death can now be forgotten. But it can make bereaved parents miss their dead child more than ever, and find it hard to bond with the new baby. Research shows women who have previously lost a baby have a much higher risk of developing post-natal illness and post-traumatic stress disorder in their next pregnancy, and up to a year after the birth of another child.

Parents say they never get over, or even come to terms with, a child's death. The Camerons will always grieve for Ivan. Cynics should be silenced by the knowledge that this may be the hardest thing the Camerons now have to embark on — more so than winning the election, perhaps.