Like most people, I find myself fascinated by the Liz Hurley pregnancy. She lived with Hugh Grant for more than a decade, then broke it off after he was arrested while in the company of a prostitute. She started up with film producer Stephen Bing and now claims to be carrying his child.

Bing denies responsibility and a paternity suit is underway in California, according to the tabloids. So the pregnancy proceeds with a tiny foetus having no idea what awaits it. Hurley and Grant are "close" once more and visiting the obstetrician, swooning over scans together.

Why the reunion? Hurley says the reason she and Grant broke up was that they never wanted a child together. In normal relationships, Hurley thinks, the desire for a child is a sign of commitment. (The prostitution incident seems to have been forgotten in the fog of revised memory syndrome, something celebrities seem to suffer even more than the rest of us.)

Now that Hurley is pregnant by some man or other - let the court-ordered DNA tests decide - Hurley and Grant can play happy families, repairing their relationship in time-honoured tradition by having a baby.

Who cares who the biological father is as long as the happy "parents" are together? Excuse me if I sound judgmental, but is this messed up, or what?

Then I read that Melissa Etheridge, a lesbian who had two children with her lover - fathered by sperm donation with the happy co-operation of his wife - has broken up with the other mother of her children. Those custody arrangements sound even messier than the conception.

It's as if all these people got their parenting values from repeated screenings of Three Men and a Baby - or Three Mothers and a Baby, whatever.

It makes me want to shake them and scream: "Babies don't solve anything!"

Yes, babies are cuddly and gratifying because they are so full of what feels like unconditional love, especially if you're a needy adult. They bond generously with whichever adults happen to be around. It makes the adults feel good.

A new baby in a house is a joy - but it's not an excuse for a love-in because, after the initial romance of new parenthood, babies are hard work.

Babies are challenging, demanding and time-intensive. They demand sacrifices of their parents.

The stress of parenthood is as likely to destroy a relationship as it is to strengthen it. Only strong, communicative relationships survive.

And - forgive me again for being a prude - but I don't think anyone should have a baby without being absolutely determined to keep the parenting relationship alive and secure throughout the child's developmental years. Too often, we favour parents' rights to have children, not children's rights to have secure bonds with responsible adults.

The come-what-may attitude to having children isn't exclusive to celebrities. There are areas of this country where you'll see more grandmothers than mothers pushing prams.

Grandmothers who'd been stuck rearing their irresponsible children's children phoned in to Joe Duffy recently: one of them had to break into her drug-addicted daughter's flat to find two children, aged one and two, hungry, cold and covered in their own excrement.

Such a fate is unlikely to befall the Hurley baby. After all, Hurley will be able to hire nannies to raise the child if she and Grant find the 24-hour-a-day responsibility too much. But that, too, can become another kind of neglect. Ask any psychiatrist.

As one friend - a successful journalist and a committed parent - said to me recently: "It's not working mothers who are selfish. The only way we manage is by giving up all time for ourselves. We work outside the home, then we come home to mind children. I haven't had a day off in years. I've never had a facial. I've never gone to the gym. I don't even have time to watch TV."

That's the reality. Babies aren't glamorous - even when they get you into Hello magazine and the tabloids. Babies don't boost a flagging career: if Hurley's having trouble getting roles now, just wait until she's a mother.

Most people who have babies, in my experience, are responsible and caring. They give up a lot but get a lot in return.

The more you put in, the greater the chance that you'll rear teenagers and young adults who want to spend time with you. That companionship, parents of young adults tell me, is one of the greatest rewards.

It's not possible when parents are narcissistic and put their own needs first. And if narcissism starts with conception - when a mother doesn't regard her child's need for a commitment from its biological father as important - what chance has the baby got?