Dimitrios Nikolaou

The unfacts of ‘request’ caesarean section

Sir, We would like to congratulate Susan Bewley and Jayne Cockburn on the comprehensive range of their recent commentary on caesarean section and the risks compared with vaginal delivery, but we were disappointed to find an obvious bias in favour of vaginal delivery. This was most obvious in their consideration of maternal mortality. They quote maternal mortality figures for 1997–1999 of 16.9 per million for vaginal delivery and 38.5 per million for elective caesarean section. The chapter by Professor Hall in the same source, specifically addressing the issue of caesarean section, indicates that this difference is not significant. In addition, this is clearly not a valid comparison: those cases of urgent and emergency caesarean section were attempting vaginal delivery. The correct estimate of maternal mortality might therefore be as high as 57 out of 1,916,000 attempted vaginal deliveries, a rate of 29.7 per million. In addition, it would be reasonable to exclude placenta praevia cases, as they have to be delivered by caesarean section, and the mortality is not related to the caesarean section itself, but is inherent to the condition (this is also acknowledged in the same chapter as above). In the same triennium there were four deaths associated with placenta praevia, two delivered by elective caesarean section and two by non-elective caesarean section. Assuming the authors are not suggesting that any of these women would have been better served by a vaginal delivery, and amending the mortality rates accordingly, there would in fact be only three deaths associated with elective caesarean section, a rate of 23.1 per million, about 75% of that associated with attempted vaginal delivery, and not much higher than the rate for successful vaginal delivery. Despite this, by the time their conclusion is reached, the authors feel happy to assert that there is a ‘. . .known and inevitable increased risk of maternal death. . .following caesarean section’. Yes, but for emergency, not elective caesarean section. We agree with the authors that the risks of all complications should be ascertained for each method of delivery so that a more informed choice can be made, but this general debate for or against caesarean section is a pointless and sterile exercise. The risk of death for an individual woman is very small (and may actually be least with elective caesarean section). In the end, the decision will be a value-judgement for the pregnant woman, who will have to balance the relative risks of everything else (perinatal mortality and morbidity, surgical morbidity, incontinence, etc.), and attempt to come to a decision which is right for her. We do not claim to know whether vaginal delivery is safer than elective caesarean section or not. The available evidence suggests that it is very likely that for maternal and perinatal mortality the differences (whichever way) are going to be very small indeed in the developed world. Everything else will always be a matter of opinion, and the cost to the NHS, and the capacity of the NHS, may be more decisive factors. The debate is ill-served when an apparently authoritative commentary is not immune from including a few ‘unfacts’ itself.

Social egg freezing should be offered to single women approaching their late thirties: AGAINST: Women should be freezing their eggs earlier

Over recent decades, women in the UK are postponing starting a family, with potential consequences for their reproductive performance. Research has shown that young people are not aware of the natural limits of female fertility and significantly overestimate the success rates of assisted reproductive technologies in helping them to conceive at an advanced age (Lemoine Am J Bioeth 2015;15:37–48).

Investigating the effect of an abnormal cervico-vaginal and endometrial microbiome on assisted reproductive technologies: A systematic review

The female reproductive tract has an active microbiome, and it is suggested that these microbes could influence the outcome of assisted reproductive technologies (ART). This systematic review aimed to assess the vaginal/uterine microbiome, specifically with regard to improving the outcome of ART. English peer‐reviewed journals were searched for studies investigating the vaginal/uterine micriobiome and female reproductive tract, using PRISMA guidelines. Twenty‐six studies were included, 19 studying the vaginal and seven investigating the uterine microbiome. Studies using culture‐based technologies found an abnormal vaginal microbiome AVM was not associated with ART outcome. However, studies using sequence‐based technologies found an abnormal vaginal microbiome had a negative effect on ART. An abnormal uterine microbiome impacted ART outcome in all of the studies which used culture‐based methods and the most extensive of the two studies using metagenomic sequencing. This review has revealed a lack of translational data relating an abnormal vaginal/uterine microbiome to ART outcomes, with inconsistencies between the results of the different studies. Therefore the nature of the relationship between the vaginal/uterine microbiome and fertility remains unknown. As we better characterize this relationship using modern metagenomic techniques, the potential to manipulate the female reproductive tract microbiome to improve ART could be a reality.