Authors’ reply re: Assisted Vaginal Birth: Green-top Guideline
No.26
Dear Editor
de Leeuw & Daly have raised a number of issues in relation to the RCOG
Assisted Vaginal Birth Guideline. 1 We have responded
previously to some of these issues, highlighting the short and long-term
morbidity associated with vacuum and forceps assisted birth, and the
relative benefits and risks of the two types of instruments.2, 3 The emphasis within an evidence-based guideline
is to cite randomised controlled trials and systematic reviews of
randomised controlled trials, where available, in preference to
observational studies. The issues of informed consent and shared
decision-making have been addressed in detail and we have responded to
the suggestion that the guideline does not provide assistance to
clinicians and women in line with the Montgomery ruling.4
The additional issue raised by de Leeuw & Daly relates to routine use
of episiotomy as part of assisted vaginal birth. We cited a multi-centre
pilot RCT and a prospective cohort study from Scotland and England both
of which showed no significant difference in the incidence OASI with
routine versus restrictive episiotomy (8.1% versus 10.9%, OR 0.72;
95% CI 0.28-1.27), and episiotomy versus no episiotomy respectively
(9.9% versus 7.7%, OR 1.11; 95% CI 0.66-1.87). To date, there has
been no adequately powered RCT to address this question. A number of
retrospective studies have been published. de Leeuw et al published a
large retrospective cohort study from the Netherlands.5 This study reported a reduced risk of OASI with
episiotomy for both vacuum and forceps but of concern was the very low
reported incidence of OASI in association with AVB, very different to
the UK and Ireland. An overall incidence of 1.2% for vacuum assisted
delivery suggests under-reporting, or under-diagnosis of OASI, and
questions the reliability of the data and its applicability. Two
systematic reviews of published studies came to different conclusions in
relation to use of episiotomy. The breadth of the published literature
on AVB and episiotomy has been presented in the guideline and the data
are conflicting.
Finally, de Leeuw & Daly have stated that the recommendation in the AVB
guideline is inconsistent with the RCOG OASI Guideline. We cited
directly from the OASI guideline recommendation which states the
following: Mediolateral episiotomy should be considered in instrumental
deliveries. [New 2015]
Deirdre J Murphy,1 Rachna Bahl,2Bryony Strachan2
1) Coombe Women & Infants University Hospital
Cork St, Dublin 8, Republic of Ireland
2) St Michael’s Hospital, Bristol