Growing numbers of boys are being born with malformed genitals. Are chemicals in our homes to blame? And what can be done about this distressing condition? Hannah Duguid reports

At 16 weeks pregnant, Isobel Lockwood had an ultrasound and was told she was carrying a baby girl. Soon afterwards, DNA taken from the foetus during an amniocentesis showed it was a boy. The doctor, who'd never made such a mistake before, was astonished but thought nothing further of it.

When Isobel eventually gave birth, the reason for the mix-up became clear. Her son's penis was tiny and split down the middle.

The immediate diagnosis was hypospadias - a birth abnormality where the hole in the penis lies underneath the shaft, or in more severe cases, at the base of the penis or underneath the scrotum. In some cases the penis is very bent and will grow back on itself, in the shape of a doughnut. In severe cases, it is difficult to identify a penis at all.

At best the problem is largely cosmetic and can be rectified in a single operation. At worst (and with modern surgery these cases are rare), boys are left infertile and unable to have sex.

Of every 150 to 200 boys born in this country, one will have hypospadias - and doctors believe that cases have doubled over the past 25 years. It happens during the first three or four months of pregnancy and is a result of incomplete masculinisation.

Basically, we all begin life in the womb as female, but with hypospadias something disrupts the hormonal changes a foetus goes through to become male. What that "something" might be turns out to be fairly chilling.

Research in Denmark points to a group of chemicals - phthalates - found in objects and everyday products all around us. They are in plastic, carpets, fabric, make-up, food packaging, perfume, cosmetics, milk, vegetables, pesticides and sun cream. Known as endocrine disrupters, it is believed they upset the delicate balance of hormones during the early stages of pregnancy.

Related to this is the general crisis in male fertility in the West. One in six boys born today will have a low sperm-count. Hypospadias sufferers are part of a much wider problem which has seen male fertility drastically decline over the past 50 years.

Professor Richard Sharpe of the Medical Research Council's Human Reproductive Sciences Unit suggests that there's a link between incidents of hypospadias, undescended testes, low sperm-count and testicular cancers. "We don't yet know the exact cause of these problems, but they are all inter-related. It seems that the increase in these abnormalities is to do with environmental and lifestyle factors. It is something that has only happened recently," Sharpe says.

Aivar Bracka, a consultant genito-urethral plastic surgeon at Russells Hall Hospital in Dudley, operates on hundreds of cases of hypospadias every year. "I would be surprised if there wasn't an environmental cause for it. It is difficult to explain any other way. In particular, it explains cases of identical twins where one is born with hypospadias and the other isn't. This means that genetics doesn't account for everything."

Hereditary factors do, however, play a part in some cases. It is not unusual for more than one male in a family to have hypospadias. If the father and grandfather has it, there is a one in three chance that the next male in line will have it.

But mostly, it happens out of the blue. "I had no idea what hypospadias was," says Sue Phipps, mother of identical twins Henry and Charlie, 11, both born with the condition. "I didn't notice immediately as I had not had boys before. The nurse pointed it out. Both of them had their hole half-way down the underneath of their penis, and both had a hooded foreskin. They had to sit on the toilet to pee, or it went everywhere.

"We were told they would need one operation, but after a series of operations their penises were a mess. The pain was so severe they were on morphine. Going to the loo was dreadful for them; Henry urinated from three holes and Charlie from five."

A traumatic two years culminated in Sue Phipps threatening to sue the surgeon. One of the problems when local plastic surgeons operate on hypospadias patients is that they are not sufficiently experienced in the delicate technique required and end up making the problem worse - one-third of cases operated on by Bracka are repair jobs.

Once referred to Russells Hall Hospital, the boys needed just one "salvage" operation to give them a penis that looked normal and worked. Both were able to get erections.

But Phipps does not yet know whether her boys will be fertile. There is a small but significant chance that they won't be. Studies have shown that boys with hypospadias tend to have a slightly lower sperm-count. The twins' testicles are normal, though. One in 10 boys with hypospadias is also born with undescended testicles. If one testicle descends there is, again, a small but significant increase of infertility. If both fail to descend, that likelihood shoots up to 80 per cent.

The other reason hypospadias sufferers may struggle to have children is if their abnormality makes it difficult to have sex. A penis with a 270-degree bend can be surgically corrected, but if it is not penetration is almost impossible - as is normal ejaculation if the hole is at the base of the penis. Ham-fisted surgery leaves the urethra "baggy", causing weak ejaculation where sperm dribbles rather than shoots out.

A penis that doesn't look or behave like everybody else's is upsetting for a boy, too. Their penises tends to be smaller than usual and, apart from embarrassment with potential sexual encounters, there is "locker room syndrome", when boys face the rough judgements of their peers.

Peter Cuckow, consultant paediatric urologist at Great Ormond Street Hospital and the Institute of Urology, says: "People are much more critical of their anatomy now, which means operations take place that wouldn't have years ago. I have known families where all the men had hypospadias but the older generations had not had operations because all that was wrong was that their penis looked strange. It still worked, so it wasn't a problem."

Isobel Lockwood says: "I am most worried about how to talk to my son about his penis. I don't want there to be any shame about it, but there's no point pretending nothing's wrong. You want them to be the same. But I do worry about what will happen when he reaches puberty."

Sometimes it is fathers who find it difficult to cope. "I suppose it's because they see it as their manhood," says Dionne Smith, 38. "When my boys went into hospital to have their operation, my ex-partner told his friends that the boys were on holiday. I didn't like that. I told him it wasn't a disease - or anything to be afraid of."

What is important is that for most boys born with hypospadias, one or two operations when they're very young will correct the condition. It is also true that surgeons expect to see more cases in the future - and unless something changes there is nothing we can really do about it.

Support group: Some names have been changed

Phthalates: what you need to know

What are phthalates?

Phthalates (pronounced "thal-ates") are a group of chemical liquids used as "plasticisers" - substances that modify the physical properties of materials. Resembling vegetable oil, odourless, they belong to a family of workhorse chemicals that have been in use for 50 years. They are created by the simple reaction of alcohols with phthalic anhydride and the elimination of water.

How do they work?

They are most commonly used to soften polyvinyl chloride (PVC), thus creating a soft and flexible texture.

What are they used for?

Items such as footwear, electrical cables and stationery, as well as medical devices such as tubing and blood bags. The larger-molecule variety is what gives flexibility to some vinyl flooring and children's toys. The smaller-molecule type serves as a fixative for perfumes to slow evaporation and help the scent to linger. Nail varnishes, adhesives and safety glass gain more supple textures thanks to phthalates.

The European Parliament will be finalising legislation this autumn on the use of toxic chemicals in household products. Greenpeace, which is locking horns with the chemical industry lobby over this issue, is working to ensure that the legislation is strong enough to make a difference.

The environmental campaign group wants to see the use of phthalates, a group of chemicals that may be responsible for disrupting hormones during pregnancy, restricted and safer ones used. It also wants the chemical content of products to be clearly stated on labels so that consumers know what to avoid.

Sarah Shoaka of Greenpeace says: "These chemicals are so widespread. We're using ourselves as an experiment and by the time we know the results, it will be too late."

Whether Greenpeace can succeed against the might of the chemicals industry remains to be seen - and no one knows for certain that, even if they do, the rise in conditions such as hypospadias can be reversed. But it does seem clear that some lifestyle and environmental factors must be addressed.

For a list of products to avoid, see