Professor Guillebaud, emeritus professor of family planning and reproductive health, said taking the combined oral contraceptives every day without breaks was the '21st century way to take the pill' at the RCGP annual conference 2017 last week.

He argued that this should become the main recommended way for women to take oral contraceptives, and the usual 21/7 regimen for the pill was ‘outdated’ and should be consigned ‘to history’.

Offering the pill on a 365/365 schedule is an off-license prescription at the moment, but is backed up by lots of evidence and supported by medical authorities in the UK and WHO, he said.

He said the recommendation to take the pill on a 21/7 regimen – thereby un-suppressing the ovary 13 times a year for seven days at a time – had been made 60 years ago, and based ‘arbitrarily on the calendar, and not on science’.

Contraceptive pill

He said implementing breaks reduced the efficacy of the pill by un-suppressing the ovary and allowing some follicular activity to return.

Although in over three quarters of women the ovaries remain sufficiently dormant to prevent ovulation, this is not the case for all women, and around 23% will see their pre-ovulatory follicles grow to such an extent during this pill-free period that they come close to the point of ovulation.

This makes them vulnerable to their contraception failing, he warned – a risk that is exacerbated if they forget to take the first or second pill of a new pack after the break, which is the time that pills are most likely to be missed.

They are also more likely to have sex during this time, after abstaining during the bleeding phase, which further increases their risk of unintended pregnancy.

Evidence suggests that continuous use makes the pill more effective as a contraceptive, and reduces problems such as period pain, PMT and migraine, Professor Guillebaud said.

It also affords a greater margin of error – most women will be able to miss up to seven pills and still be protected against pregnancy, even if they had sex in that week, he said.

Menstruation

This will therefore have the added benefit of reducing demand for emergency contraception.

It also means women would not face the inconvenience of regular monthly menstruation, which he said have ‘no known health benefits’.

He added that patients who still want to have periods could consider taking it on a schedule such as 84/4 – but recommended pill-free periods of no more than four days long to minimise the risk of contraception failing.

He said: ‘Good learning requires some unlearning – I want us to unlearn the idea that the combined pill is a good method of contraception: it is not – if it is taken on a 21/7 regimen.

‘We argue for substituting improved regimens that do not intermittently cease to provide full ovulation suppression.'