Article: Mandy Collins from True Love

Also, whereas our parents got married at 21 or 22, most people these days only get married in their late 20s, more often in their early to mid-30s.

What many women may not realise, however, is that while they're getting on with their careers and establishing themselves financially ­- and, of course, there's nothing wrong with that -­ their fertility's steadily declining.

And if you want children, but haven't got those eggs fertilised by the time you're 35, you're leaving things more than a little late. Besides, one needs to look beyond the actual pregnancy and childbirth itself to the demands of parenting.

A stressful venture

A woman aged 40 or 50 doesn't have the vitality, energy and fitness of one in her 20s, so coping with a child - particularly a very young one ­- is likely to be more stressful.

And the generation gap's likely to have widened to the point where the child can't share interests, problems and activities with their mom, however much she may try to stay abreast of the contemporary scene.

What's more, it may not be totally fair to have a child when you know your own life expectancy's only 50-75% of a younger mother's: if you have a baby at the age of 40, for example, you know you only have about 20 years of active life left yourself. So, when your child's a teenager, you'll probably already have retired.

And by the time your child's married and has his or her own children, you may well not be around to enjoy the experience of grandparenthood.

Dr Merwyn Jacobson of the Vitalab Fertility Centre in Johannesburg says women shouldn't cling to fantasies of falling pregnant in their late 40s because they've read a news report about someone famous who's had a baby at 45 or 50.

Fertility declines

"Chances are, those celebs didn't use their own eggs," he points out, and goes on to cite some alarming statistics.

"Until the age of about 35, we anticipate a normal pregnancy rate of about 80% per year," he says. "But by the time you're 35, your fertility's starting to decline. At age 40, that rate has fallen to about 50% per year and at age 45, it's 15-20% at best.

"The miscarriage rate also increases with age," he continues. "Up to age 35, it's about 5-10%. By age 40, it's up to 50% and by age 45, you have about a 75% chance of miscarrying.

"This is because your eggs are no longer working well; therefore the embryo's at greater risk of not being healthy."

Dr Jacobson points out that while Down's syndrome is among the most common problems associated with pregnancy in older women, there are also other chromosomal abnormalities that may occur -­ and, again, the risk increases almost exponentially with age.

And if you've waited a long time to fall pregnant, being faced with a child who's physically or mentally abnormal may come as a doubly devastating blow.

Built for children

Physiologically, Dr Jacobson explains, women are built to have children young -­ ideally in their 20s, because the tissues in your body recover much more quickly.

"When you're in your 30s, you become aware of tissue changes," he says. "These are often associated with lifestyle ­- your tissue takes a hammering, especially if you've been a regular smoker or drinker."

Of course, Dr Jacobson's not suggesting we all have children when we turn 20, come hell or high water. "There are emotional and social considerations too," he says. "The warning is just that you shouldn't leave things until it's too late."

The other consideration is just how fertile or infertile your partner is. "What usually happens is that the urge to have a baby hits you and you meet Mr Right -­ not necessarily in that order," says Dr Jacobson. "And Mr Right has a 40% chance of potential infertility himself. Never forget that part of the equation."

But it's something many couples forget ­- they may spend a fortune trying to establish why the female member of the couple can't fall pregnant, and only think of having the man's sperm tested when they've already run the gamut of female fertility treatments on offer.

Then they often discover she's actually fine, while he's been the one with the problem all along. But back to the social and emotional issues. Planning to have children isn't just a physiological decision you make, either because your body's ready for pregnancy or because you think your biological clock's whirring at the speed of sound.

Consider responsibilities

You need to be able to support a child financially, as well as be emotionally ready for the responsibility -­ two very important considerations.

So, if you've decided you want children someday, it's important to seriously consider the age issue. So if you're heading for 35 and haven't started working on having your eggs fertilised (either naturally or artificially), remember, your fertility's about to start declining fast.

In addition, advancing age also has an impact on your general health. Pregnancy can compound existing medical conditions, and those conditions can make your pregnancy difficult.

"Your general health's as important as your fertility," declares Dr Jacobson. "As you age, your cardiovascular, respiratory and liver functions decline and your body mass increases because you become less active."

The message is clear: for the sake of your fertility, your health and a better shot at a healthy normal pregnancy and baby, err on the side of youth and don't keep putting off pregnancy until it's too late.