“Can I just have a quick word with you?” the midwife asked during a quiet spell on the delivery suite. “Just between me and you, we need IVF and I wondered if an endometrial scratch is a good idea?”

It was 2015, and I’d just got back from a fertility conference. Professor T C Li, was the keynote speaker. He had flown in from Hong Kong to deliver his talk ‘Endometrial Scratch and Hysteroscopy before IVF’. He concluded it won’t work if you scratch everybody, but might for women with recurrent implantation failure. 

Endometrial scratch was in vogue. A survey from IVF Worldwide showed the majority of clinicians  offered one to women before an IVF cycle. A few small trials had been reviews by Cochrane, the gold standard for assessing research and the authors concluded “moderate-quality evidence indicates that endometrial injury performed between day 7 of the previous cycle and day 7 of the embryo transfer cycle is associated with an improvement in live birth”.  Nonetheless, they went on to state this was only for women with more than two previous embryo transfers and further research was needed.

I advised my midwifery colleague not to pay £350 for a scratch. She ignored my advice, paid and got pregnant. “I’m so pleased I had the scratch” she told me a few months later. 

An endometrial scratch involves taking a thin flexible tube that lets clinicians take a sample of the lining of the womb creating a small scratch. An embryo is transferred back a month or so later. 

The idea is that the scratch would cause inflammation which would somehow modify the immune system, making the embryo more likely to implant. 

The scratch procedure, despite its innocuous name, is not exactly harmless. Most women find it painful, which isn’t surprising considering it is intended to cause endometrial injury. Side effects also include nausea, fainting and excessive bleeding. Some women have even required admission to the emergency department. 

The other name for a scratch is a pipelle endometrial biopsy. Originally designed to sample the womb lining in women with abnormal bleeding to detect endometrial cancer it was rebranded by IVF doctors. Cynics may reason that calling it a scratch sounds more friendly to patients, who are charged between £150 to £300 for it, with a significant profit margin.

Where are we now?

Four years later, research has moved on. A large study carried out in clinics all over the world found that an endometrial scratch before the first cycle of IVF makes no difference to the outcome treatment. Lead study author Sarah Lensen says, “we would recommend that clinics stop offering this.” A second UK based study looking at exactly the same thing, scratch before first cycle of IVF is due to report later this year.

Yesterday, I bumped into a friend of mine. His PhD was focussed on endometrial scratch. He too did a small single centre trial which showed no difference. Sadly he can’t get it published, journals keep knocking it back as it doesn’t offer anything new. 

While these studies have clearly answered the question for women setting out on their first IVF cycle, what about those with recurrent implantation failure, or recurrent miscarriage. Cochrane said the studies were moderate-quality. The subsequent research focussed on a broader population, women at the start of treatment and is not applicable to other groups. Sadly, I doubt research funders will be willing to support another trial.

So four years ago T C Li was right, it won’t work if you scratch everyone. Now clinicians are just left to scratch their heads.

Authors

Dr Matt Prior

Matt is an NHS Consultant in Newcastle with over ten years of experience. His PhD research into subfertility and miscarriage involved developing a clinical trial and patient engagement.