Epidurals!

Epidural anaesthesia is a painkiller, usually clonidine in the case of childbirth, injected into the space between the vertebrae in the spinal cord.

Epidurals are good at relieving pain and don’t harm babies.

A meta-analysis of randomized controlled trials found that epidurals (compared to opioids, which don’t relieve pain noticeably) don’t affect fetal oxygenation, neonatal pH, Apgar score, caesarean delivery, or the use of forceps.[1] A second meta-analysis also concluded that epidurals don’t increase the rate of C-sections or forceps.[4]

Epidurals do significantly increase labor time, by a mean of about an hour. They also cause fever (in about a quarter of women) and hypotension (in about 40%).[2]

People who choose epidurals may be more likely to also get C-sections (about 2.5x in a case series of 711 patients, for instance[6]),  but randomized trials and natural experiments in which epidural utilization goes up show consistently that epidurals don’t cause increased rate of C-sections.[2]

And people love epidurals; they are significantly more satisfied with their pain relief than people randomized to opioids, p < 0.001.[2]

Now, the problem with labor delays is neonatal asphyxia. The longer you push, the more likely the baby is going to come out with a low Apgar score.  Babies who go without oxygen can get brain damage, which can cause developmental disability or cerebral palsy.

If you’re pushing for three hours, you have only 0.1x the odds of a spontaneous vaginal delivery without signs of asphyxia that you would at two hours; at two hours, you have only 0.4x the odds of a healthy spontaneous vaginal delivery than you would have at one hour.[3]

On the other hand, this effect seems not to be strong enough to lower mean Apgar scores overall when mothers are randomized to epidurals.

In an observational study of 1,028,705 Swedish newborns, only 0.76% had low Apgar scores (below 7). Epidurals were a significant risk factor, but note that difficult births are more likely to be especially painful.[5]

The evidence that associates epidurals with significant badness (low Apgar scores, higher rates of forceps use and Caesareans) is pretty much entirely observational, and the randomized trials don’t bear it out.

 

Unless you value natural childbirth for its own sake, or want the lower maternal infection risks associated with a home birth, there’s really not much of an evidence-based case for avoiding epidurals.

[1] Leighton, Barbara L., and Stephen H. Halpern. “The effects of epidural analgesia on labor, maternal, and neonatal outcomes: a systematic review.”American Journal of Obstetrics and Gynecology 186.5 (2002): S69-S77.

[2]Halpern, Stephen H., et al. “Effect of epidural vs parenteral opioid analgesia on the progress of labor: a meta-analysis.” Jama 280.24 (1998): 2105-2110.

[3]Le Ray, Camille, et al. “When to stop pushing: effects of duration of second-stage expulsion efforts on maternal and neonatal outcomes in nulliparous women with epidural analgesia.” American journal of obstetrics and gynecology 201.4 (2009): 361-e1.

[4]Liu, E. H. C., and A. T. H. Sia. “Rates of caesarean section and instrumental vaginal delivery in nulliparous women after low concentration epidural infusions or opioid analgesia: systematic review.” Bmj 328.7453 (2004): 1410.

[5]Thorngren-Jerneck, Kristina, and Andreas Herbst. “Low 5‐Minute Apgar Score: A Population‐Based Register Study of 1 Million Term Births.”Obstetrics & Gynecology 98.1 (2001): 65-70.

[6]Thorp, James A., et al. “The effect of continuous epidural analgesia on cesarean section for dystocia in nulliparous women.” American journal of obstetrics and gynecology 161.3 (1989): 670-675.

Giving Birth: How To Reduce Risk Of Badness

First things first: the mother is basically not going to die in childbirth.  Maternal mortality rates in the US are 14 per 100,000, or a 0.0014% chance, or a few hundred deaths a year. This is not a thing to worry about. You are not gonna die.

Maternal mortality is much more likely, by a 3:1 ratio, among black mothers than white (or Hispanic) mothers. Nobody really knows why.

Most of the things that kill mothers in childbirth are hemorrhage, eclampsia, stroke, pulmonary embolism, high blood pressure, or other factors associated with the higher blood pressure and clotting associated with pregnancy.[2]

Severe maternal morbidity, or life-threatening consequences of childbirth, are more common, affecting about 65,000 women in the US per year.  This is quite a bit more common, though still unlikely overall; there is a 1.6% chance something seriously bad will happen to you during birth.

How about babies?  Perinatal mortality, or a child dying within a week of childbirth, happens at a rate of 6.24 per 1000, or 0.6%.  Perinatal morbidity (i.e. something going wrong enough to require NICU admission) has higher rates, at 77.9 per 1000 births, or 7.8%.[4]  The majority of these are low-birth-weight infants.

Want to avoid bad things happening to your baby during birth? Don’t have a preemie.

How do you avoid having a preemie again? Twins are bad; smoking is bad; treat your gum disease and vaginal infections; don’t be underweight; get cervical incompetence fixed if that’s an issue.

Badness around birth happens mostly to babies and especially to preterm babies.

Is Homebirth Safe?

According to a Cochrane Review, randomized trials on low-risk women (70%-80% of pregnant women are “low risk”) find no difference in outcomes between home birth and hospital birth.[4] Among 24,092 low-risk pregnant women, perinatal (infant) mortality was not significantly different between home births and hospital births; there was a lower incidence of low Apgar scores (OR = 0.55) in the home birth group. Home births were less likely to involve interventions such as induction or augmentation of labor, episiotomy, caesarian section, or using forceps.  A large (529,688 low-risk pregnancy) cohort study in the Netherlands also found no significant differences in perinatal mortality between planned home births and planned hospital births.[6]

However, another meta-analysis found that home birth tripled the neonatal mortality rate compared to hospital birth.[7]  This study, by contrast, included not randomized trials but cohort studies of planned home birth vs. planned hospital births.  A total of 342,056 planned home and 207,551 planned hospital births were included. Home births had significantly fewer interventions (such as epidurals, forceps, or caesarean sections) and better maternal outcomes (OR of infection = 0.27, OR of hemorrhage = 0.66, etc.)  Perinatal deaths, e.g. infant deaths within seven days of birth, were the same between home birth and hospital birth; but neonatal death, within 28 days of birth, was higher in home births (OR = 1.98).  0.2% of home births, compared to 0.1% of hospital births, resulted in neonatal death.

The authors give the explanation that intrapartum anoxia (due to laboring without a fetal heart rate monitor and not switching to caesarean or forceps as often) can cause infant mortality.

Bottom lines:

  • home births definitely involve much less medical intervention
  • home births involve fewer maternal complications
  • home births seem to involve higher risk of neonatal but not perinatal deaths
  • all of the above evidence is for low-risk pregnancies.
  • If you have a low-risk pregnancy your baby is probably not gonna die either way. 0.1%-0.2% risks.

If all you care about is baby safety, it looks like hospital > home birth, even for low-risk pregnancies. If you include mother’s safety, it becomes more complicated, because maternal outcomes tend to be better with home births; but keep in mind that maternal deaths are still extremely rare either way, much more so than infant deaths. If you include maternal pain, it becomes more complicated still, because you can get an epidural at the hospital.  And if you include maternal stress, then, some people report that being in a “medicalized” environment is more worrying than being at home. The tradeoffs, as always, are individual.

 

 

References

[1]http://data.worldbank.org/indicator/SH.STA.MMRT

[2]http://www.cdc.gov/reproductivehealth/maternalinfanthealth/pmss.html

[3]http://www.cdc.gov/nchs/data/nvsr/nvsr64/nvsr64_08.pdf

[4]Harrison, Wade, and David Goodman. “Epidemiologic trends in neonatal intensive care, 2007-2012.” JAMA pediatrics 169.9 (2015): 855-862.

[4]Olsen, Ole, and Jette A. Clausen. “Planned hospital birth versus planned home birth.” The Cochrane Library (2012).

[5]Olsen, Ole. “Meta‐analysis of the safety of home birth.” Birth 24.1 (1997): 4-13

[6]de Jonge, Ank, et al. “Perinatal mortality and morbidity in a nationwide cohort of 529 688 low‐risk planned home and hospital births.” BJOG: An International Journal of Obstetrics & Gynaecology 116.9 (2009): 1177-1184..

[6]Wax, Joseph R., et al. “Maternal and newborn outcomes in planned home birth vs planned hospital births: a metaanalysis.” American journal of obstetrics and gynecology 203.3 (2010): 243-e1.