Lionel Shriver: Don't fool with my body clock. Just give me some back-up

We need help with the laundry, not a biological egg-timer

But then, like most halfway-educated Western women, I am not an idiot. Childless at 48, I know I am closing on menopause, whose average onset is 51. I know that my chances of conceiving have been in nosedive since 35.

Fertility is fiddly, and the introduction of a glorified egg-timer runs the risk of giving women a sense of false certainty. A partner's low potency, miscarriage (more common as we age), other reproductive health problems such as endometriosis, and plain bad luck can also imperil a pregnancy. True, for some women being able to look over at the bed stand and see the wand of their biological clock set clearly at, say, 44 may impel them to move on the baby business sooner. I know that when my alarm is set especially early, I can't sleep.

Yet the many women who put off pregnancy these days are not necessarily deluded about how much time they have left to procreate. Nor are young so-called career women (isn't it interesting, that there's no such thing as a "career man"?) necessarily determined to be egotistically "fulfilled," family be damned. Indeed, one of the ugly surprises for the post-liberation females of my own generation was that work is, well, work. Most jobs entail tiring, boring drudgery, and are anything but fun. So why do it? Why not stay home and make little Britneys and Jamies?

Get real! Have you looked at your mortgage payment lately? They need the money! Few young men these days assume that they'll carry the full weight of breadwinning, nor should they; that arrangement was never fair to men, either. And unless one partner has a heavy-hitting job, it's extremely difficult for a couple to survive financially without both of you in work.

This notion that women can quit the workforce for years to raise children and then pop back into the same employment once the kids are in school is the stuff of fantasy. Do men with gaping holes in their CVs make as attractive job applicants as go-getters with a seamless track record? If a woman does have a career that's starting to take off, the most disastrous thing she can do is get pregnant. (When my editor for a soon-to-be-published novel announced to me that she was pregnant, I nearly cried. She was on maternity leave during the vital lead-up to publication, and on release the book did nothing. A year later, she was sacked.)

Women still do more than their share of housework and childcare. Mums are still under far greater pressure than dads to put other ambitions nobly aside and dote on the kids, and for big-for-their-britches bitches like me that kind of self-effacement doesn't come easily. We pay sentimental lip-service to the glories of motherhood, but in truth accord the calling a lower status than rubbish collection. I can't count the women I've met at parties who, asked what they do, have looked at the carpet and apologised that they're "only" mothers.

We do not need an egg-timer. We need better childcare, more help with the laundry, and someone else to stir the bolognese because Jamie just threw up. We need a little respect. Then maybe we won't put off what comes more naturally in our twenties and early thirties, because you put off what you dread.

Lionel Shriver's most recent novel is 'We Need to Talk About Kevin' (Serpent's Tail, 2005)