Common anaesthetic could make contraceptive less effective – study

Women must be warned that a common anaesthetic could make their contraception less effective, researchers said, after a study suggested patients are not being routinely informed of the risk.

Doctors at a London hospital trust found no record within the medical notes of relevant patients that they had been given advice on the risks of contraceptive failure due to the drug sugammadex, which is widely used in anaesthesia.

The drug, given towards the end of the operation to reverse the action of drugs given earlier in surgery to relax the patient’s muscles, is known to interact with the hormone progesterone, the researchers said.

This means it can reduce the effectiveness of hormonal contraceptives, including the progesterone-only pill (mini-pill), combined pill, vaginal rings, implants and intra-uterine devices, they added.

Doctors at the department of anaesthesiology at University College London Hospitals NHS Foundation Trust surveyed anaesthetists at their hospital trust on their use of sugammadex.

Of the 48 women of childbearing age who they deemed should have been given advice on the risks, none had any record of such a conversation in their medical notes, the researchers said.

As well as this, 70% of the 82 anaesthetists who responded to a survey at the trust said they do not routinely discuss sugammadex with the patients who have received the drug.

Dr Matt Oliver, one of the leaders of the study, said: “We only studied one hospital trust but we expect the results to be similar elsewhere in the UK.”

Another of the researchers, Dr Neha Passi, described their findings as “concerning”.

Dr Passi said: “Use of sugammadex is expected to rise as it becomes cheaper in the future and ensuring that women receiving this medicine are aware it may increase their risk of unwanted pregnancy must be a priority.”

“We expect the results to be similar elsewhere in the UK