Tag Archives: informed consent

The longer-term effects of CS for breech in Denmark

Screen Shot 2014-08-15 at 06.30.06Something is rotten …

Well, I suppose a backlash was inevitable. Due to the campaigning of women and the willingness of a significant number of health care providers to provide women with a real choice when it comes to breech childbirth, the argument for re-skilling to better support breech births has been gaining momentum. But this week saw the publication of two studies arguing this is not such a good idea.

First it was a Dutch group (Vlemmix et al 2014) who made the argument that at 1.3/1000 compared to nil, vaginal breech birth (VBB) results in ten times the mortality of planned CS. They overlooked the need to match the word ‘planned’ with an intention-to-treat analysis, and their own research (Vlemmix et al 2013) suggesting that neonatal mortality was doubled in pregnancies following an elective CS compared to those where a VBB was planned in the first pregnancy (2.5/1000 vs 1.3/1000). (Read my response here.)

When baby's head has descended into the pelvis, the pubic bones are directly behind the occiput

When baby’s head has descended into the pelvis, the pubic bones are directly behind the occiput

Now a Danish study asks, “Can Caesarean section improve child and maternal health? The case of breech babies” (Jensen and Wust, 2014). Wait, did I read that right? Are we asking whether CS can improve maternal health? Really?

Unlike their Dutch counterparts, Jensen and Wust have decided: “In our estimation sample, we observe only few infant deaths for breech babies. Thus we do not consider this very rare outcome in the proceeding analysis.” One country decides this outcome is a deal breaker, another feels it is so rare that it is not necessary to consider it.

Jensen and Wust present a lot of beautiful graphs and calculations showing that there was a noticeable improvement in Apgar scores and a reduction in visits to the GP, but no significant change in serious morbidity (ill-health) or hospitalisations in the first three years of life, following the sudden increase in elective CS for breech associated with the publication of the Term Breech Trial in 2000.

Although I am in favour of attempting to calculate the longer-term effects of such sweeping changes, I am concerned about what they did and did not choose to speculate upon.

Their most statistically significant finding was an increase in prolonged maternal hospitalisation following an elective CS. This has noticeable financial implications, which they calculated, but they do not address the increase in costs and risks in future births. The financial blind eye is concerning, but their conclusion that CS does not affect the health of the mother, without considering future births, is even more disconcerting.

On the other hand, they speculate that the additional expenditure for elective CS is balanced by costs savings as a result of significant reductions in cerebral palsy and subsequent care needed. They did not have information on actual rates of CP in this population. Instead, they reference a 2001 study by Krebs, which did NOT note a relationship between CP and mode of delivery, and found in 20,000 breech births a total of 4 serious long-term disabilities and 18 minor disabilities possibly related to low Apgar scores. They ignored Krebs previous research (1999) indicating that an increase in CP for breech-presenting babies was NOT associated with mode of delivery. They also ignored a recent systematic review and meta-analysis (O’Callaghan and MacLennan 2013) demonstrating that CS does NOT reduce the risk of CP for breech-presenting babies.

It’s important to get this right. Low Apgars are definitely associated with increased CP and other problems in head-down babies, possibly because the birth itself less often causes minor asphyxia, and therefore the cause is often an underlying fragility. In Krebs’ work, he found the association was mostly with small for gestational age infants; this corresponds with other breech research which consistently associates smaller babies with poorer outcomes. But because many breech babies have lower Apgars as a consequence of the way they are born, Apgars are not such a clear indicator of future risk in this population. They were not in the Term Breech Trial (Whyte et al 2004), and that is the best evidence we have to go on at the moment.

The main outcomes shown in this research are an increase in overall Apgar scores and a decrease in visits to the GP in the first year, less significantly in the second year, and not significantly different in the third year of life. They found no increase in significant neonatal morbidity or hospitalisations in the first 3 years of life. Although it was not originally one of their primary outcomes, the GP visits could be significant. It could also be that in the wake of a major change in practice suggesting that breech-born babies are at increased risk, everyone’s a bit nervous in the first couple of years? We need more information regarding these babies’ actual health problems to understand and use this data, because it conflicts with a Finnish study which found the opposite was the case at 7 years (Ulander et al 2004).

So Jensen and Wust have given us more research indicating an increase in short-term morbidity (with mortality being rare and insignificant?) but no difference in significant neonatal morbidity and the need for increased medical care after 2 years. This matches the information from the Term Breech Trial. Despite the authors insistence they have uncovered evidence that CS is best for all breech babies, and that it is ultimately cheaper (based on their non-evidence-based speculation on future costs of CP only), it actually adds to the literature confirming no concrete evidence of a difference in long-term outcomes for breech babies. Just goes to show you how you can take a group of statistics and put just about any spin on it you like, especially if your mathematical ability makes your analysis fairly impenetrable to most people. (Good thing I live with an actuary.)

Screen Shot 2014-08-15 at 06.30.06Turning now to the elephant in the room

Being born vaginally may be more risky for some babies than being born by CS. Most of the evidence seems to indicate that, in the short-term at least, using standard lithotomy delivery practices, this is the case. On the other hand, most of the long-term evidence does not indicate lasting effects.

What concerns me about literature like this, which makes predictions about what would be saved or not, financially or physically, with this approach or that – is that women, as long as they are human, will continue to have their own unique approach, and they should. That is what being human is about. Many will want to deliver their breech babies by CS, and they should have access to that care, even if it means a greater financial burden. And many will want to give birth vaginally, even in awareness that the rare outcome of neonatal mortality is more likely to happen to them, even in the awareness that if something goes wrong, they will need to live with it for the rest of their lives. We will always have death, and handicapped children that require our grief, our love and our devotion. This cannot be eradicated. Women deserve to be able to make this very personal decision without being made to feel criminal.

Instead of continuing to do research which tells us what we already know, we should invest in research exploring modern management strategies which are showing promise in reducing risk to babies born vaginally, so that women who live in countries where there ought to be a choice actually have one, and women who live in countries where CS is either inaccessible or a real danger to their health have the best chance of going home with a healthy baby. We should stop trying to have the last word on how breech babies should be born, let women decide how to balance the complex array of risks and benefits in their own lives and families, and develop our skills at being ‘with woman’ and her breech.

Shawn

Can we eliminate all risk for breech babies?

Closer to my heart, by Leah Sandretsky,  www.etsy.com/shop/heartbeatstudio

Closer to my heart, by Leah Sandretsky, www.etsy.com/shop/heartbeatstudio

This week (August 2014), a Dutch research team published the results of a large retrospective cohort study concerning the results of all breech births in the Netherlands. They concluded that an increase in the caesarean section rate following publication of the Term Breech Trial (TBT) has resulted in a significant reduction in perinatal mortality related to breech presentation, and therefore a policy of universal caesarean section for breech would improve outcomes for breech babies even further.

In the year prior to October 2000 (the team does not present data from earlier than 1999; why not?), the perinatal death rate was 1.3/1000 for all breech deliveries (VBB and CS inclusive). Elective sections increased from 24% prior to publication of the TBT to 60% afterwards, and from December 2000-2007, the perinatal mortality rate was 0.7/1000 for all breech deliveries, with an overall VBB rate of 22%. Moreover, the team showed that all of the perinatal deaths occurred during what they called planned breech deliveries (although their understanding of ‘planned breech delivery’ is very different from mine, as I discuss below), so the actual perinatal mortality rate for breech babies born vaginally remained steady at 1.6/1000 during both periods.

A rate of 1.6/1000 is actually quite low compared to the mortality rate of approximately 1/100 reported in the Term Breech Trial. However, the authors propose that the results of this study should replace the information currently given to women in Dutch national guidelines, because according to their calculations, “A policy of elective caesarean section for all term breech deliveries could lower the overall term neonatal mortality in term deliveries by 6.8%, from 172 to 162 per year.”

Unfortunately, it’s not so simple.

Dreaming the impossible dream.

A 'normal' breech baby - well-flexed, with lots of room to move

A ‘normal’ breech baby – well-flexed, with lots of room to move

The first problem with this prediction is that it’s not possible to pursue a policy of elective caesarean section for all term breech deliveries, even if you ‘convinced’ the 40% of women who choose to plan a VBB in the Netherlands to plan a CS. The researchers themselves noted that approximately 1:5 of the perinatal deaths observed occurred when breech presentation was not diagnosed until birth. Without instituting expensive changes to breech screening on a national basis, these outcomes will not necessarily be improved, certainly not without performing many more risky caesarean sections in advanced labour. (When these births were excluded from the analysis, the perinatal mortality rate for VBB’s which were actually planned was 1.3/1000 overall. The Netherlands has a high rate of home birth, so some of these unplanned VBB probably occurred at home with surprised, rather than prepared, midwives.)

Also, the researchers note that they have not performed an intention-to-treat analysis of their data. Multiple studies have noted that approximately 10% of women who plan caesarean sections go into labour unexpectedly before their scheduled operation, and 9.7% of the woman randomised to CS in the TBT gave birth vaginally. The researchers say that those for whom this was the case ‘could not be included in the caesarean section group’ for their study. Why? Were they included in the ‘planned’ vaginal breech birth group? The authors note this category was a ‘composite of vaginal delivery and emergency cesarean.’ Regardless of whether these women actually planned a VBB?

In an intention-to-treat analysis, the outcomes for babies who turn head-down spontaneously would also be included, as the decision to plan a VBB influences whether or not they will. In the Term Breech Trial, twice as many turned when a VBB was planned than when a CS was planned, so that 3.8% of all babies who planned a VBB were born in a cephalic position. Failing to do an intention-to-treat analysis disregards the complexity of breech decision-making and the full range of consequences.

Putting the figures into perspective.

664730The researchers note that 40% of women in the Netherlands choose to plan a vaginal breech birth, in collaboration with their doctors and midwives, and approximately 55% of them achieve this. This results in an overall perinatal mortality rate for breech presenting babies in the Netherlands of 0.7/1000, which happens to be the same perinatal mortality rate for low-risk women giving birth in hospital settings in the Netherlands (de Jong et al 2009; the mortality rate was slightly lower for women who planned a home birth at 0.6/1000). From where I am sitting, this looks like a good example of collaborative decision-making reducing risk while preserving choice.

Earlier this year, another team also led by Vlemmix (2013) published an abstract in the AJOG using further data from the Dutch nationwide perinatal registry from 2000-2007. This demonstrated that in addition to greatly increased maternal morbidity, neonatal mortality in pregnancies which followed an elective CS for breech presentation was 2.5/1000, compared to 1.3/1000 following pregnancies where a VBB was planned (which will be an average of the 2.5/1000 risk following a CS, and substantially lower risk following successful planned VBB’s). How then does this affect the prediction that elective caesarean section for all breech presentations would further significantly reduce the overall national perinatal mortality rate? Only if these women do not have any more children. Seems worth a mention to me, when you are recommending that all breech babies with a neonatal mortality risk of 1.3/1000 be delivered by CS.

Consider statistics given in the RCOG guideline on Birth After Previous Caesarean Birth. They summarise the data relating to term VBACS: “Planned VBAC is associated with a 10/10,000 risk of antepartum stillbirth beyond 39 weeks of gestation and a 4/10,000 risk of delivery related perinatal death (if conducted in a large centre).”

So a woman choosing to await spontaneous labour past 39 weeks and attempt a VBAC has a 1.4/1000 risk of losing her baby, but this is not only perceived as a reasonable decision, it is positively encouraged in most hospitals in the UK. Entire midwifery-led care pathways are set up to support women making this choice, and primiparous women to whom elective section for breech is recommended are proactively counselled that they can feel positively about attempting a VBAC the next time around.

But a woman choosing to birth her breech baby vaginally, knowing that she has a 1.3/1000 chance of losing her baby, is suspect. Does anyone else get the feeling we are robbing Peter to pay Paul?

The researchers identified no sub-classification of women for whom breech birth was more risky, or less risky compared to CS. They did observe that babies with a birth weight of over 3500 g (often excluded from VBB) actually only had a perinatal mortality rate of 0.8/1000. Contrary to what they have concluded, encouraging any woman who plans to have more children and wishes to attempt a VBB (at a relative PMR of 1.3/1000) as opposed to advocating universal elective CS for breech (and exposing subsequent children to double the mortality rate, at 2.5/1000), seems a measured approach.

The team’s representation of morbidity statistics also distorts the picture, as long bone fractures (included in their composite statistic) are common in cephalic births as well. They heal well, and are not generally considered ‘serious morbidity.’ Nonetheless, the morbidity rate of 22/1000 reported in this research was also significantly less than the rate of approximately 1/20 reported in the Term Breech Trial.

Designing research which meets the needs of women and their partners

Descending LST, anterior buttock leading

Descending LST, anterior buttock leading

The researchers have called for the results of their study to replace the information in their national patient information leaflets, which are based on the data from the Term Breech Trial, including the information that outcomes at 2 years of age did not differ between planned VBB and planned CS. One of the authors named in this Vlemmix study has also conducted research into what information matters most to women and their partners (Kok et al 2008).

Kok’s study (2008) demonstrated that women were mostly concerned with the safety of their baby and fear for a handicapped child, and that the 2-year outcome was what mattered most to them. Why then has this team conducted yet another study telling us what we already know – that short-term morbidity and mortality is significantly greater when VBB is planned in most cases – rather than robust research addressing what matters most to the families making these decisions? Whyte’s team (2004) emphasised that the 2-year results surprised them, as the group of children who went on to have handicaps at 2 years of age did not overlap at all with the group of children who experienced severe morbidity in the neonatal period. They were all born apparently healthy, and in the Vlemmix study would have been included in the ‘proof’ that universal CS is a safer policy. Given the numerous studies demonstrating a higher risk of cerebral palsy and other adverse outcomes for breech-presenting babies regardless of mode of delivery (O’Collaghan and MacLennan 2013), the question of whether the babies we save from death in the first 7 days go on to lead full and healthy lives is a fundamental question. And it is the concern which matters most to women.

On the other hand, according to Kok et al (2008) the concern which matters most to women’s partners is the outcomes for women. This study reported only 2 maternal deaths in the 1999-2007 period, despite acknowledging another study already published by the Dutch Maternal Mortality Committee reporting 4 deaths following elective section for term singleton breech in the Netherlands in 2000-2002 alone.

Why are the women disappearing?

If this study does not address the central concerns of women and their partners, why should it take precedence in the information given to aid informed decision-making? If the authors have not performed an intention-to-treat analysis, how can they possibly claim to know that their treatment will have the predicted result? If the study has demonstrated a risk similar to that of planning a VBAC, why are both choices not considered equally reasonable?

These authors are all very much involved with research concerning external cephalic version (ECV) and also feel the results of this research demonstrate the need to use ECV more liberally in order to reduce the incidence of breech presentation at term. While I am a fan of their ECV research and a proponent of ECV as a readily available option for women with breech presenting babies, again we cannot ignore the fact that ECV has not yet been demonstrated to improve neonatal outcomes, possibly for the same reasons the 2 year outcomes for children are not affected. However, ECV does significantly reduce the CS rate for women, particularly in centres where the option of VBB is not well supported. Again, I would like to see this highly experienced and highly influential team turn their attention to answering questions we do not already know the answer to, including whether or not manually turning a breech baby from a breech to a head-down position improves the short- and long-term outcomes for these babies, beyond increasing their chance of being born vaginally.

Shawn

De Jonge, A., van der Goes, B.Y., Ravelli, A.C.J., Amelink-Verburg, M.P., et al. (2009) Perinatal mortality and morbidity in a nationwide cohort of 529,688 low-risk planned home and hospital births. BJOG : an international journal of obstetrics and gynaecology. [Online] 116 (9), 1177–1184. Available from: doi:10.1111/j.1471-0528.2009.02175.x [Accessed: 12 August 2014].

Vlemmix, F., Kazemier, B., Rosman, A., Schaaf, J., et al. (2013) 764: Effect of increased caesarean section rate due to term breech presentation on maternal and fetal outcome in subsequent pregnancies. American Journal of Obstetrics and Gynecology. [Online] 208 (1, Supplement), S321. Available from: doi:http://dx.doi.org/10.1016/j.ajog.2012.10.102.

Vlemmix, F., Bergenhenegouwen, L., Schaaf, J.M., Ensing, S., et al. (2014) Term breech deliveries in the Netherlands: did the increased cesarean rate affect neonatal outcome? A population-based cohort study. Acta Obstetricia et Gynecologica Scandinavica. [Online] 93 (9), 888–896. Available from: doi:10.1111/aogs.12449 [Accessed: 12 August 2014].

 

Breech Birth After Caesarean (BBAC)

Another post responding to maternity service user demand for better information and more individualised care for breech presentation, prompted by a discussion on the Coalition for Breech Birth Facebook group.

In these days of growing awareness of the risks associated with doing too many caesarean sections, women planning an elective section for breech presentation are informed that they can and should be encouraged to try for a vaginal birth after caesarean section (VBAC, or just BAC). Yet how many are informed that she has a 1:10 chance of the breech presentation recurring in the next pregnancy (Coughlan et al 2002, Ford et al 2010)? And that if her second baby is breech there is almost a 1:3 chance that her third will be? That this likelihood is increased if she, her mother or her father were breech (Nordtveit et al 2008)?

‘Breech’ remains an issue for many women throughout their reproductive lives, so much so that some have argued it is ‘physiologically normal’ for some women (Albrechtsen et al 1998). And many women will have spent time between pregnancies considering the information which led them to choose an elective section, and arriving at a very different point of view by the end of their second pregnancy.

The Royal College of Obstetricians and Gynaecologists’ guideline lists a ‘scarred uterus’ (which would include post-CS, as well as other uterine surgery, such as myomectomy) as a contraindication to a vaginal breech birth (VBB). However the guideline also refers to one (small) study which specifically looked at success rates for BBACs:  Ophir et al 1989 had really good outcomes, and a higher rate of successful vaginal birth than many series report. But bigger numbers would be more reassuring, and they need to be compared to results for other VBACs.

(Incidentally, a previous CS is often considered a contraindication for ECV as well, but I found no studies demonstrating an increase in uterine rupture. Burgos et al 2014 looked at this and reported no uterine ruptures in 70 ECVs. Higher numbers would be more reassuring, but this is the problem with breech research – higher numbers are tricky to come by!)

The PREMODA study reported two adverse outcomes for BBACs, which accounted for 2/3 of the deaths they concluded could have been prevented had elective sections been performed at 39 weeks. One woman arrived to the hospital with contractions, but no fetal heart tones. The other woman experienced a spontaneous uterine rupture at 40 weeks, when a VBB was planned. Both complications associated with a pregnancy following a CS in general, not BBAC labours.  Oh, how unfortunate it must have felt – for the families and for the researchers – to have their beautiful breech outcome stats affected by the CSs they were trying to prevent! Understandably, given the current climate which blames any adverse outcome on the breech, they recommended BBACs be avoided.

We talk a lot about risks of labour, but increasing evidence points to risks of not labouring as well. Two obstetricians, Sinha and Bewley (2010) point out in their article, ‘Myth: babies would choose prelabour caesarean section:’

Babies who do not experience labour have significantly increased respiratory and other morbidities that may have profound effects on development, determining immediate and potentially life-long disease. It is thus surprising that obstetricians do not advocate awaiting or inducing labour even in women considering CS. (from the abstract)

Ulander et al al 2004, a Finnish team, draw similar conclusions in their comparison of breech, vertex and caesarean deliveries, ‘Are health expectations of term breech infants unrealistically high?:’

As regards the long-term outcome of the children, the only statistically significant difference was in the number of visits to out-patient departments which were less frequent for breech infants born vaginally than breech infants born through CS (OR 0.70, CI 0.53–0.93) or vertex infants born vaginally (OR 0.58, CI 0.47–0.72) (Table III). The cumulative incidence of long- term morbidity was lower in breech infants born vaginally than in breech infants born by planned CS (OR 0.47, CI 0.28–0.80). (p 83)

Any future research on breech or VBAC should include these long-term outcomes as well. Ulander et al found that the risks of birth trauma were smaller for breech-born babies than for cephalic-born babies, but smallest over all for CS-born babies. Undoubtedly, labour introduces some risks — especially first labours, VBAC labours, breech labours. But like many things in life, sometimes taking those risks results in long-term benefits, which can only be perceived further along down the road. A BBAC is a reasonable choice, which should be supported.

What additional precautions might be in order? A dysfunctional labour is a risk factor for both VBAC and breech labour. Especially if the birth will occur in a unit that does not routinely recommend and promote vaginal breech birth, and thus will not be saturated with experience, inducing or augmenting a BBAC is asking for trouble.

Shawn

Further Research:

  • Bourtembourg, A., Mangin, M., Ramanah, R., Maillet, R., et al. (2013) [Breech delivery and scarred uterus: A special obstetrical situation?]. J Gynecol Obstet Biol Reprod (Paris). 42 (4), 351–358. Conclusion: Vaginal breech delivery in case of a scarred uterus is possible, if each obstetrical situation is correctly studied to authorize a vaginal birth trial after a careful selection of patients and a strict management of labour. Vaginal birth does not seem to increase maternal and neonatal morbidity and mortality in this situation.

How the consent process introduces bias into RCTs

Part 1: Why I remain sceptical of RCTs concerning obstetric interventions in normal labour and birth

Another blog post in response to a Twitter debate .. this time concerning various RCTs currently evaluating IOL vs expectant management. We’ve been discussing three trials:

The questions are valid. We know stillbirth is increased, especially in certain populations, the longer a pregnancy continues. In order to make an informed decision, many women will want to know the most likely outcomes and effects of opting in or out of proposed interventions. RCTs are considered the most unbiased way of settling these issues, unsullied by the biases of women or health professionals.

The problem is, these interventions are eventually applied to a population that is, due to being human, inherently biased. Some women feel a strong preference in one direction, some in another; and some want their doctor to decide for them. Women need to consent to be randomised into RCTs, and women who are most averse to the proposed intervention simply decline consent. Therefore the population recruited becomes slightly biased towards a preference for the intervention being investigated.

Is this important? Does it matter? I don’t know. Recent research by Wu et al suggests that women with a strong preference for vaginal birth were more likely to have a vaginal birth. RCTs cannot tell us the effect of women’s preferences on the outcomes they measure. Yet in theory their results are used to offer women an option they will almost certainly have an opinion about.

If I were contributing to the design of these trials, I would want to collect observational data alongside the main trial data. Things like:

  • Why do women consent or decline to participate in the RCT? Are the women who declined to participate due to a strong preference against induction more or less likely to have a normal birth? Are the outcomes for their babies significantly different than those in either arm of the trial?
  • What are the long-term outcomes? Especially in the over-35 population, an increase stillbirth rate may be due to inherent weaknesses in the baby. Significant long-term differences are often not detectable until 2 years of age.
  • And finally .. would they do the again? Would they recommend it to a friend?

These are questions best answered using quantitative techniques, but women may have different questions or priorities, which we will only discover using qualitative investigations.

See Part 2: Why midwives are sceptical.

Shawn