Oxford scientist says '50 years spent avoiding truth' over Primodos birth defect link

  • ITV News Meridian's Social Affairs Correspondent Christine Alsford spoke to Professor Carl Heneghan about his research

A scientist from the University of Oxford who carried out extensive research into the pregnancy test drug Primodos claims the evidence is clear about the harm it causes.

Professor Carl Heneghan from The Centre for Evidence-Based Medicine has published work looking at studies that covered some 70,000 women who took the oral hormone pregnancy tests in the 1960s and 1970s.

The professor told ITV News Meridian that nothing has changed his mind about the results of his findings five years on.

Professor Heneghan said: "What we found was a clear association with all congenital malformations that included heart disease, limb deformities and nervous system deformities.

"I'd say this is one of the most straightforward cases I've seen where an exposure has led to congenital malformations that I've seen in my 30 year history.

"For 50 years we've been running round in circles trying to avoid getting to the truth."

Hundreds of women believe the two pills, which were given out by family doctors, led to birth defects, still births and miscarriage.

1.5 million women took the oral hormone pregnancy test in the 1960s and 1970s. Credit: ITV News Meridian

It was given to more than a million women in the UK by family doctors, before warnings were added to packaging and the drug was taken off the market in 1978.

Primodos was made by a company called Schering, now owned by Bayer, who say there is no causal relationship.

But Professor Heneghan says the work he undertook, examining nearly 30 different scientific studies on the drug, had worrying implications for its use by pregnant women.

He says his research shows it increased the risk of having a baby with a malformation.

"If you asked a single doctor whether they would they prescribe this drug today, the answer would be no," he said.

"If I ask a doctor, 'Do you consider this drug is safe?' it's very clear; every single doctor says no."

The Centre for Evidence-based Medicine at the University of Oxford. Credit: ITV News Meridian

Families who say they have been affected have campaigned long and hard over decades for action to be taken but the government has said it will only look at the issue again if new scientific evidence comes to light.

The Medicines and Healthcare products Regulatory Agency (MHRA), which regulates medicines, said an independent review of Professor Heneghan’s study was carried out and concluded it did not present evidence that was sufficient or robust enough to change the scientific position published in 2017.

The MHRA said: "We remain hugely sympathetic to the families who consider that they have suffered because of using Hormone Pregnancy Tests (HPTs).

"The independent Expert Working Group (EWG) review included a public call for evidence and rigorous assessment of all the available scientific evidence at the time.

"The report published in November 2017 concluded that the data did not support a causal association between the use of Hormone Pregnancy Tests, such as Primodos, and adverse pregnancy outcomes. The government and MHRA accepted this conclusion.

"The Government has always been led by the scientific evidence and has committed to reviewing any new evidence related to HPTs and a possible causal association with adverse pregnancy outcomes.

"Patient safety is at the heart of everything we do and we keep the safety of medicines under continuous review."

The drug cannot be given to pregnant women now, so instead, some research has been done on zebrafish embryos instead.

Professor Neil Vargesson from the University of Aberdeen. Credit: ITV News Meridian

Professor Neil Vargesson from the University of Aberdeen used fish to complete a study using high doses of the drug components in their water.

He said: "We saw damage to the blood vessels, damage to nerves, damage to the brain, the ears, the eyes, the fins and the yolk sack particularly. Because of the damage to the nerves they also had trouble with movement."

Now, he's carried out further investigations.

He said: "More recent research, which we're trying to get published later this year, is now showing that really quite low doses of the primitive components cause quite subtle damage to the embryos.

"So it causes problems to the heart, to the fins and to the ears."

Professor Neil Vargesson used fish to complete a study using high doses of the drug components in their water. Credit: Prof Neil Vargesson, University of Aberdeen from Brown et al., 2018, Scientific Reports

The drug company Bayer said: "In 2017, the Expert Working Group of the UK’s Commission on Human Medicines published a detailed report concluding that the available scientific data from a variety of scientific disciplines did not support the existence of a causal relationship between the use of sex hormones in pregnancy and an increased incidence of congenital anomalies in the newborn or of other adverse outcomes such as miscarriage. 

"The Committee for Medicinal Products for Human Use of the European Medicines Agency supported that conclusion.

"Bayer maintains that no significant new scientific knowledge has been produced which would call into question the validity of the previous assessment of there being no link between the use of Primodos and the occurrence of such congenital anomalies."

Campaigners have fought long and hard for action on Primodos but two previous legal challenges did not rule in their favour, with cases being thrown out.

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