A woman died two days after starting IVF treatment from a rare complication of the therapy, an inquest was told.
The condition is a rare risk of fertility treatment
Temilola Akinbolagbe, 33, from Plumstead, south London, collapsed at a bus stop after developing Ovarian Hyperstimulation Syndrome (OHSS).
The potentially fatal form of the condition affects about one per cent of women undergoing IVF, although a less severe form is more common.
Experts believe this was the first such death from OHSS in the UK.
Mild and moderate forms of OHSS have been reported to affect up to 20% of women undergoing ovarian induction, which mimics the production of normal hormones.
It is believed there have been three other deaths from the condition in the last 30 years.
Mrs Akinbolagbe, from Plumstead, south London, started to feel ill after receiving fertility treatment.
She was taken to hospital immediately, but suffered a massive heart attack.
Mrs Akinbolagbe's life support machine was turned off five days later.
Her husband, Samuel Ifaturoti, said his wife had been "very positive" about the fertility treatment.
'Not a particular risk'
Gynaecologist John Parsons said staff at Kings College Hospital, where she had received her fertility treatment, were all shocked by Mrs Akinbolagbe's death.
He said: "We make a point of identifying women who are at risk of OHS but sometimes we do not detect these women.
"Mrs Akinbolagbe's ovaries had small cysts and this sometimes precedes the condition.
"But she did not have the hormone features that precede these problems or the menstrual irregularity. She was not a particular risk."
He added: "The chance of something disastrous happening, like this, is very rare indeed."
Mrs Akinbolagbe developed pelvic vein thrombosis, which led to her cardiac arrest.
She had suffered only minor symptoms before, including pains in her neck and head.
Dr David Morell, chairman of the Association of Clinical Embryologists, said he believed this was the first case of a woman dying from the condition in the UK.
"While developing OHSS is rare among women having IVF treatment, death from this is extremely rare."
Clare Brown of Infertility Network UK said: "Although ovarian hyperstimulation is rare, it is nonetheless a risk which patients should receive detailed information on before embarking on treatment."
Angela McNab, Chief Executive of the Human Fertilisation and Embryology Authority, said: "This tragic case shows that standard IVF still carries risks, as does all medical treatments.
"We will be continuing to remind clinics of their duty to ensure that side effects of treatments are properly managed and that patients are properly informed and know what to do if they start to feel unwell during their treatment."
Matthew O'Gorman, spokesman for the pro-life charity Life, said: "This tragic case serves as a salutary warning of the dangers associated with IVF.
"Ovarian hyper-stimulation carries various health risks that are mostly avoidable through the alternative, positive fertility treatment that LIFE provides."
A verdict of misadventure was recorded after the inquest at Southwark Coroner's Court into Mrs Akinbolagbe's death.