Saturday, November 20, 2010

Do Epidural's result in more C-sections or birth complications?

As an expectant father, my wife and I have been attending prenatal classes in anticipation of our first little one. Over the last couple weeks the topics of discussion have largely centred around interventions commonly used in the birthing process. These include oxytocin, epidural anesthesia, forceps, vacuum extraction, and C-section among others. Fear and confusion tend to be the common sentiments of most of the expectant parents (ourselves included) and so the intent of this entry is to help bring some clarity and understanding.

As a physician shared and informed decision making is my goal when discussing treatment options with patients. In order to do this effectively, we need to have an understanding not just that treatment "A" will increase risk for outcome "B", but more importantly by how much will it be able to do so. For example, if someone were to tell you that taking an aspirin a day would decrease your risk of having a heart attack, you'd likely think you should do it, despite the fact that it can cause GI bleeding. But what if the amount that it decreased your risk was only by 0.5% (ie from 8% to 7.5% risk over the next 10 years)? Then, when faced with how small the benefit it, you may decide otherwise. The key is having some sort of context for quantifying the risk or benefit, not just a statement that something may help or harm.

In order to get some answers, I spent some time reading research articles that asked the questions "do epidurals increase the risk of needing more medical intervention", and "do epidurals result in adverse outcomes for mothers and babies?". Before discussing what I've found, I should state that as a Naturopathic Doctor I do not have expertise in the area of obstetrics, nor do I deliver babies. The research I've done is that of someone who has a personal interest in the questions being asked, and a reasonable amount of expertise in interpreting scientific data. I should also state that as a naturopath, my bias would be toward avoiding unnecessary interventions. I also want to state that the following discussion is for women who are on their first baby, and who are not induced. I'll do this in three sections: no difference category, increased risk category, and increased benefit category. That said, here we go!

1. No difference.

The higher quality trials I looked at, and the meta-analysis (a statistical pooling of a bunch of separate trials) suggest that there is no increased risk of having a c-section for women receiving an epidural. There was also no difference noted in neonatal outcomes as evidenced by their apgar scores. One study of interest looked at a hospital in Missouri that compared groups of women giving birth before and after the hospital gave on-demand epidural service. They found that monthly total c-section rates were the same before and after they were made available on demand, indicating that increased rates of epidurals didn't increase the total rate of c-sections. Interestingly, when they looked more closely at the patients who had epidural on demand, they found that the women who were having dystocia tended to be the ones that were asking for epidurals. What they concluded was not that epidurals increased rates of c-section, but rather women who were already having difficulty with their labour tended to be the ones who requested epidurals. In that instance, it was difficulty labouring that resulted in higher c-section rates vs the epidural being the cause. Another question of interest is will an epidural increase risk for long term backache? Again, no difference.

2. Increased risks.

As for increased risks from epidural anesthesia? The consensus among most of the studies I read were that epidurals did 2 things: 1 - prolonged the second stage of labour by an average of 15-30 minutes; and 2 - increased risk for needing instrumentation (forceps, or vacuum extraction). Estimates range from anywhere between a 25-38% increase in risk relative to those who don't have an epidural. That may initially sound high, but to get a sense of what that really means you need to know what the risk is to start with. For example, if in most normal circumstances the risk of needing instrumentation for delivery is about 10%, an epidural would increase it to between 12.5%-13.8% (10% base risk, plus 25% of that 10%, which is 2.5%). Think of it like money: if your initial risk is $10, and you increase that by 25%, your total risk would be $12.50.

Serious adverse events are also possible with any intervention, however these tend to be rare. One study in the UK looked at the previous 500,000 births involving epidurals. They reported 108 events, of which 5 resulted in a permanent disability.

3. Benefits.

Interestingly, when women are polled after their birthing experience, satisfaction rates among women tended to be higher in the groups that had epidurals.

Conclusions.

Through my cursory reading of some of the literature surrounding epidurals and childbirth, I've learned that epidurals are a reasonable and relatively safe form of coping with pain in labour. Although there are always risks associated with such interventions in the short term (many of which were not addressed here), overall they don't seem to increase the need for c-section in most normal circumstances, or cause serious long term complications to mother and baby. I hope this has helped dispel some confusion and quantify some of the risks. It certainly has for me.

Regards,

Bryn

1 comment:

  1. Bryn...enjoy reading through your posts!! I headed in to labour with the idea that least medical intervention as possible was how I wanted to bring our babe in to the world. But I definitely wasn't prepared for how much it hurt!!! When my midwife suggested that after a prolonged labour an epidural may be a good option I jumped at it and it was such a good decision as I was alert and able to be totally present as our son was born. I went from being very anti-epidural to realizing that it can be a very valuable tool. I feel the information I received beforehand was that it would some how take away from the birth process and I would be all drugged up. The complete opposite was true as I was in so much pain that I had completely shut down. Shortly after the epidural was given, my son was born, I was able to walk around after delivery and we even went home the evening after a very early morning delivery. Best of luck to you guys!!!

    ReplyDelete