But now Cindy Crawford, apparently seven months pregnant, not that you'd have noticed, has gone and ruined it all by being photographed for the cover of American fashion industry bible W. Like Demi Moore on the legendary issue of Vanity Fair, she's posed naked but is looking exactly the same as usual, except for a gentle swelling at the front. And we thought Cindy was the one sane supermodel.
Showing off like this is just giving hope and succour to evil men (oh all right, not just men) who think you can grow another human being inside your body and not change shape. So there's no question anymore of relaxing about the way you look when ensuring the future of humanity. The fashion and lifestyle industry has appropriated pregnancy and made it another style statement. The bump? Only New York's coolest accessory! (Actually that's true, because it means you've persuaded a man to impregnate you - not all that easy over there, so it seems.)
But it's scarcely a style statement if you also get lumpy all over, or your complexion goes haywire, or you suffer from any of the other complaints of pregnancy (numerous, and mainly of an embarrassing nature). Thanks to Cindy et al, any ordinary pregnant woman will feel she has to stay (imagine Rachel-out-of-Friends voice) "In Control". Pulled together, as they say in the States.
Yet the reality is that pregnancy is one of the many things in life that you are not remotely in control of. Cindy Crawford makes a living out of looking incredible, so I should jolly well hope she does shrink to fit post-partum. But she might have had terrible morning sickness and been forced to eat continually to fend off nausea. Or she might have had irresistible cravings for Ben and Jerry's Double Trouble or just have felt unexpectedly depressed and desperate for pizza. And it's not over till it's over. At seven months, you may feel that your tummy is about as taut and drum-like as is legal or decent, but by nine-and-a-half it will be, well, just ridiculously, completely OTT. Not funny any more, in fact.
In the real world, far away from shoots with supermodels, pregnancy divides into some obvious stages. There's that initial, difficult, fat stage, when people can't make up their minds whether you're expecting or just gaining weight for your summer holidays. Then there's the stage when other women start to smile at you in the lift, but men are completely oblivious. Then there's the neat bump stage, when people congratulate you on how trim you're looking and friends want to poke you to see what it feels like.
And finally, my dears, there's the Space Hopper stage, when your head, arms and legs are mere excresences on the greater organism that is your womb. My baby was a week late, and I spent a month at home, drifting aimlessly from room to room, needing to pee at 20-minute intervals, and making myself double-decker sandwiches to pass the time. I mean to say, pregnant women aren't allowed to drink, or smoke, or take drugs, or have any fun at all really, so I do think we should be left in peace to eat what we want. I seem to remember I put on another half stone out of sheer boredom.
The authors of pregnancy books reckon that women put on a stone and a half during pregnancy. That's half a stone for the baby, half a stone for the placenta, and half a stone for bigger bosoms and general extra padding. (You see, I was right: you do need to put on weight to have a healthy baby.) But of course, most women put on more than that. This is because it's hard being pregnant and frankly we need all the breaks we can get. There's one particularly scary American pregnancy book which I had the misfortune to come across. ( I won't name it for legal reasons.) Apart from something called the Best Odds Diet (how to grow a genius in the comfort of your own body), there's a chapter for husbands with sub- headings like "What if my wife gets fat and I no longer desire her?" Instead of saying "You sad, sad little man, she is carrying your child, cut her some slack", it says something along the lines of, "If your wife orders fried chicken in a restaurant, simply quietly and firmly instruct her to substitute an undressed salad." Excuse me?
How tempting it is to believe that your baby is a bit like a major new project at the office. I run my team successfully, you think to yourself. I'm on top of my work load. I can handle my responsibilities. Why should pregnancy be any different? When I was thinking about trying to have a baby, I bought a book all about planning for your pregnancy. Six months before you even come off your contraception, it advised, you should give up fags, booze, chocolate, everything nice basically, and turn your body into a lean, mean pregnancy machine. And I took it seriously! I did. For about five minutes. Then, I found myself pregnant after a Christmas of drinking far too much and one particularly evil day spent smoking quantities of someone else's Silk Cuts. And even when I knew I was pregnant, I wasn't perfect either, I can tell you.
Which is all simply to say that few people are as saintly when carrying a child as they might wish to be, about food or anything else, because after all, it's still your body too, not just a receptacle for your baby. And every pregnancy is different, just as every labour is different. You might stay quite thin, or you might get very fat. It's largely a matter of luck, and there are no rules.
Now here's the good news. While it's true that having a baby leaves some people larger, a little-known fact is that it can also make you smaller. Although I put on about two stone, I lost three (but remember, breast feed, breast feed, breast feed because it's simply marvellous if one wants to reduce). People are rather outraged actually. How can you be thin! You've just had a baby!
That enormous tummy will go back to normal. It will, honestly. So will those huge bosoms. You have to think of any little wrinkles as honourable battle scars. And of course there's also a heavenly baby to carry on your hip. Now that's what I call an accessory.
WHAT REALLY HAPPENS TO YOUR BODY
! During pregnancy you will need 500 more calories a day than the usual 2,000-2,500.
! The amount of weight put on varies between 9-13.5kg (20-30lbs) with the most rapid weight gain usually between weeks 24 and 32.
! Your uterus, the baby, the placenta and the fluids account for more than half of your total weight gain. You also produce more blood and you lay down fat to prepare for lactation.
! Women are usually advised to reduce their level of exercise by around 30-70 per cent.
! During pregnancy some women gain weight between the shoulders, on the upper back, around the knees as well as on the hips and thighs. This is an important energy store for when you start breast-feeding.
! Skiing, horseriding, and high impact sports are not recommended after the 20th week. And sorry ladies, but waterskiing is totally banned.
! For most women the extra pounds gained during pregnancy will disappear in the year after the birth. Some may need to adopt healthier eating habits and take more exercise to lose the weight.
Sources: `New Pregnancy and Birth Book' by Dr Miriam Stoppard, (Dorling Kindersley), pounds 9.99; `I Want to Have a Baby?' by Dr Sarah Brewer (Kyle Cathie), pounds 12.99