For the past 18 months, Karen and Ian Whitehead have become accustomed to thinking in fours. Four cots, four high chairs, four car seats and four of just about every other baby requirement you can think of. It is an expensive business, but as parents of 20-month-old quadruplets, they have no choice.

The Whiteheads, from Swanley in Kent, had been married for six years when they began IUI (intra- uterine insemination), a form of fertility treatment. The result was four healthy girls, Laura, Hannah, Lisa and Katie, born in March 1992 and one of eight sets of quadruplets born that year in Britain.

When Ian and Karen were told that four children were on the way, practical problems didn't even enter their heads. Once the girls came home at seven weeks, however, problems had to be addressed. When she was 20 weeks into her pregnancy, Karen's doctor advised her to give up her job as a computer operator, and Ian, a fleet car salesman in a job which relied heavily on commission, became the sole breadwinner.

In the past, these burdens might have been lightened. Thursday sees the 10th birthday of probably the most famous multiple birth children in Britain, the Walton sextuplets. The six girls, the first surviving sextuplets in this country, attracted a huge amount of attention. This brought sponsorship deals with a chain of chemists, a discount on a specially adapted vehicle, appearances in television documentaries and interviews sold to newspapers. All helped to cushion the blow of suddenly having to provide for six children.

But while six children have press appeal, any fewer are not considered so special. The Whiteheads have had to rely on family and friends for help with buying the essentials: cots, high chairs and a 'quadmobile', a much-appreciated leaving present from Karen's colleagues. Through his work, Ian was able to secure a valuable nappy contract with Unichem for a year.

'Unfortunately, that's finished now and we're spending about pounds 25 a week on nappies,' Karen says. They also received free baby food for a year from Cow & Gate. 'All the baby food companies were more than willing to help. It's things like shoes that are a big expense. We bought them a pair each a while back which lasted about three months; that cost us pounds 70.'

Having four babies has also swallowed up any spare space the Whiteheads had in their three-bedroomed house. 'Our next big worry is whether we should move and make our lives miserable by taking out a huge mortgage. Karen is still a good three years away from being able to return to work, so I think we'll just have to keep plugging away here for as long as we can,' Ian says. With the cost of a childminder in the South-east averaging pounds 15 per day per child, it would not make financial sense for Karen to return to work until the girls are school age.

After-care provision, or the lack of it, was another problem. 'My health visitor was great and suggested lots of places I could get help, but nobody's got any money to spend on multiple birth families,' Karen says. 'Any help from your local health authority is based on goodwill. It also varies so much from one area to another.'

Help did arrive from a respite organisation called Crossroads Care, which normally relieves carers of the elderly and terminally ill. Soon after the births volunteers came out to help Karen when she needed to escape for a couple of hours. 'Crossroads was great. It's not an organisation that usually caters for multiple birth families, but they moved the goalposts for us,' Karen says.

What is already a stressful time for multiple birth families can often be exacerbated by the natural curiosity of the public. Ian's feelings about this were summed up in a cartoon he saw in their Twins Club magazine. 'There's a woman walking down the road with a pram and she's wearing a big sandwich board saying, 'Yes, they're quads, yes, we did have fertility treatment and, yes, we know the weddings are going to be expensive.' We used to get these sort of questions all the time.'

Karen says: 'A friend of mine has triplets and a complete stranger walked up to her in the supermarket one day and said at the top of her voice, 'I bet you had piles when you had them.' We laugh at these stories now, but at the time it did feel as if we were public property.'

The Whiteheads have had some publicity through the quadruplets. Television appearances included Kilroy and Sky TV's Live at Five. They have also featured in a car advertisement and a local newspaper article when the girls were born.

'We haven't pushed it though,' Ian says. 'We realised early on that quadruplets are not that special. Our local newspaper did a follow-up on their first birthdays, but it was only about four lines. We got paid for the TV appearances and the magazine ad we did, but you have to weigh up how much effort for how much reward. For Kilroy we had to be in the studio all day with the girls, and we got paid pounds 16, which just about covered our petrol costs.'

Most new mothers face loneliness and isolation, particularly if they have given up work and miss the companionship of adults. Karen feels she is lucky in this respect because having four babies to look after has left her little time to think about anything else. She also continues to receive support from a Crossroads helper twice a week, and another volunteer, Pauline, has become a friend. 'They've all kept me afloat really. Sometimes we all go shopping together or to a playgroup or a twins club. I think if I hadn't had them, loneliness could have become a big issue for me.'

The hardest time was in the first few months when she was mostly alone with the girls. 'My biggest worry was that the buck stops here. I'd never had one child before, let alone four, and it felt like such an awesome responsibility. One of the girls would be crying and somebody would ask what's wrong and I'd be sitting there thinking, 'But I don't know, you tell me.' '

Karen and Ian agree that having four babies at once has affected their marriage. 'It did put an enormous strain on us,' Karen says. 'When we were both working we were on a similar plane, but now we're in totally different worlds. On holiday Ian has his eyes opened again because sometimes he forgets what it's like when you're at home with them all day. There was also a time, in the first six months, when he didn't really see the girls. He'd be home from work after six o'clock and they'd be in bed because by then I'd had enough.

'Yes, we do have disagreements and, no, he doesn't always understand when I'm permanently tired. But you do what other couples do when they're going through a rough patch - you work it out between you, bounce back stronger and off you go again. But I'm not saying it's a perfect situation because it's not.'

Ian says: 'I never mention my work at home because there's enough to worry about. I leave it on the doorstep, walk in and then concentrate on the girls. We find we don't have time for each other any more, and all we seem to talk about is babies. We've got our problems with tiredness and worrying about money. But it's never as bad as when we thought we couldn't have children.'

Karen believes they have been able to cope so well because they both desperately wanted a family. 'You've got to have a common bond for it to work - you've got to both be pulling in the same direction. But even if you're a good team, having a large family still puts pressure on you.'

As more childless couples turn to fertility drugs and assisted conception techniques such as in vitro fertilisation (IVF) and gamete intrafallopian transfer (Gift), multiple births are increasing.

In the UK, 9,134 pairs of twins were born in 1991, while the 1982 figure was 7,114. For triplets the figure from 1991 was 238 sets, compared with just 78 nine years earlier.

The Human Fertilisation and Embryology Authority's annual report of 1991 looked at the overall multiple pregnancy rate resulting from IVF treatment. It found that where three embryos were transferred into 3,067 women this resulted in 211 twin pregnancies and 54 triplet pregnancies. The multiple birth rate from IVF treatment was thus 32 per cent, a 4 per cent increase on the previous year.

The prospect of more multiple births has meant that organisations such as Tamba (the Twins and Multiple Births Association), which celebrate its 15th anniversary this year, are aware of the need to promote the special circumstances of multiple birth families. But Gina Siddons, Tamba's administrator, is concerned that not enough is being done to help. 'Unfortunately, there's no extra provision from the state. A family with quads, for instance, would be entitled to the child benefit payment of pounds 10 per week for the first child, but only pounds 8.10 for the other three.

'Multiple birth families don't benefit from hand-me-downs like a normal family would and parents have to buy a lot of extra equipment. We've spoken to the Government several times about this, but they seemed to have forgotten, or perhaps are just ignoring the existence of these families.'

The Department of Health's child benefit policy unit argues that allowing exceptions for different types of families would make the benefits system too complicated to administer.

In the meantime, families such as the Whiteheads will continue to rely on the goodwill of family, friends and charitable organisations. 'Our parents have been great,' Karen says. 'Whatever we've asked of them they've said yes, including babysitting. We'd never ask our friends to do it, it wouldn't be fair. Four babies are such a responsibility - and anyway we'd quite like to keep our friends] To be honest, though, we're normally too tired to go out.'

Happy as they are, they admit it would be nice to be financially more secure. 'If someone knocked on our door and said, 'Would you like a four-bedroomed house for doing a bit of advertising for us?' I'd say, 'Absolutely sir, where do you want me to stand?', but this is 1993 and these things don't happen,' Ian says. 'But the girls aren't here to earn us money. A family is what we both wanted more than anything else in the world.'

(Photograph omitted)