Chances of pain reduction
The best evidence for pain reduction following surgery comes from blinded randomised controlled trials:
The main evidence for pain reduction using an ablation technique comes from Professor Chris Sutton’s trial at The Royal Surrey County Hospital, Guildford, published in Fertility & Sterility in 1994 which showed that 62.5% of women with Stage I-III endometriosis had significant pain reduction at 6 months post-surgery (further reading)
with 90% of those still with pain relief at one year (further reading).
The main evidence for pain reduction using an excision technique comes from Jason Abbott’s and Ray Garry’s trial published in Fertility & Sterility in 2004 which showed that 80% of women with Stage I-IV endometriosis had significant pain reduction at 6 months post-surgery (further reading).
The above data suggested a superiority of excision over ablation, however the main comparative evidence for this now comes from Jyotsna Pundir and Peter Barton-Smiths’ systematic review and meta-analysis published in the Journal of Minimally Invasive Gynaecology in 2017 which showed significantly greater improvements in some aspects of endometriosis pain with excision compared with ablation.
Peter Barton-Smith’s Doctoral Thesis further suggested that the extent of improvement was better with excision compared with ablation for some modalities of endometriosis pain (further reading).
We use 3D in all our laparoscopic and robotic procedures as recent evidence suggests an improved pick up rate of endometriosis lesions with 3D (further reading).
Chances of fertility improvement
The best evidence for spontaneous fertility improvement from surgery for endometriosis comes from The Cochrane database (further reading) which suggests that the relative risk of spontaneous pregnancy is 1.64 after removal of mild to moderate endometriosis.
There is good evidence that excisional surgery for endometriomas provides a more favourable outcome than drainage and ablation with regard to recurrence of the endometriomas, recurrence of pain symptoms, and subsequent spontaneous pregnancy in women who were previously subfertile (further reading).
This must be balanced against a published 2.4% risk of premature ovarian failure with bilateral endometriomas if excision is used, which would severely damage fertility chances (further reading).
For severe deep infiltrating endometriosis, the chance of IVF success without prior surgery is around 29% and the chance of spontaneous conception after surgery for deep infiltrating endometriosis is around 28.6% meaning that both may have similar outcomes, but the surgery carries greater risk. A combination of both approaches may give a success rate up to 46.9% (further reading). The choice of approach in an individual woman will depend upon age, ovarian reserve, pain problems, economic resources amongst other factors.
Risks of surgery
The risks of surgery for endometriosis are related to the experience and skill of the operator, the technique used, and the technology used to carry out the technique. The risk of major complications in removal of superficial disease by conventional laparoscopy are generally low (well under 1%) with an experienced operator. With severe deep infiltrating disease using a conservative excision shave technique, the risk of major complication is around 7% (further reading). With robotic surgery we have reduced these risks through improved view, precision and ergonomics (see research paper) down to 2.5% in our own clinic.