Source Article By Chris Kresser:
Natural childbirth V: epidural side effects and risks
Before we dive into a discussion of epidural analgesia I’d like to clarify my intention in writing this series in light of some of the comments on previous articles.
The purpose of this series on natural childbirth is to demonstrate that homebirth is as safe – if not safer – than hospital birth for low risk pregnancies, and that medical interventions commonly used in hospital births such as epidurals, induction with synthetic oxytocin and cesarean sections have risks and complications that are often not communicated to pregnant women.
Currently fewer than 1% of births happen at home in the U.S., and I believe this is largely due to misconceptions about its safety. My intention here is to correct those misconceptions.
The purpose of this series is not to condemn the use of these interventions in all circumstances. All of them have their place, and can be very helpful and even life-saving (for mothers and babies) when used appropriately. In fact, I said the following in bold text at the end of the first article in this series:
I want to be clear: no matter where birth takes place, complications may arise that require medical intervention and I am 100% in support of it in these cases.
There is still much we don’t understand about birth, and even more we don’t have direct control over. In some cases, despite a woman’s best efforts to have a natural, undisturbed birth, complications arise that require medical attention (and transfer to a hospital if she started laboring at home). In these circumstances, I absolutely endorse taking advantage of whatever interventions may protect the health and safety of both the mother and baby. At the end of the day, that is far, far more important than the method by which the baby was born.
I also want to be clear that I am not judging women who choose to have hospital births, receive epidurals, induce with Pitocin or end up having a cesarean section. I respect the right of women to choose a method of childbirth that feels safe and comfortable for them.
My purpose, instead, is to tell the side of the story that women are often not told, and to raise awareness of the risks associated with these procedures so that when it comes time to make their own decision, women are adequately educated and informed to do so.
What is an epidural and how common are they?
Dr. Leonard J. Corning, a neurologist in New York, was the first physician to use an epidural. In 1885 he injected cocaine into the back of a patient suffering from spinal weakness and seminal incontinence.
Today, epidurals are by far the most popular method of pain relief during labor in U.S. hospitals. According to the Listening to Mothers II survey (2006), more than 75 percent of women reported that they received an epidural, including 71 percent of women who had a vaginal birth. In Canada in 2005-2006, 54 percent of women who gave birth vaginally used an epidural, and during those same years in England, 22 percent of women overall had an epidural before or during delivery.
In an epidural, a local anesthetic – still derived from cocaine – is injected into the epidural space (the space around the tough coverings that protect the spinal cord). Epidurals block nerve signals from both the sensory and motor nerves, which provides effective pain relief but immobilizes the lower part of the recipient’s body.
In the last decade, a new type of epidural has been developed (called “walking epidurals”) that reduce the motor block and allow some mobility.
Spinal analgesia (a.k.a. “spinals”) are also used for pain relief during labor, but unlike conventional epidurals, they allow women to move during labor. In a spinal, the analgesic drug is injected directly into the spinal space through the dura, producing fast-acting, short-term pain relief.
Epidurals have significant impacts on all hormones of labor
In the last article, Natural Childbirth IV: The Hormones of Birth, we discussed the exquisite orchestration of hormones during birth and the risks of interfering with the body’s natural hormone regulation.
Unfortunately, epidurals interfere with all of the hormones we discussed.
They inhibit beta-endorphin production, which in turn shuts down the shift in consciousness (“going to another planet”) that characterizes undisturbed birth.
Epidurals reduce oxytocin production or keep it from rising during labor. They also blunt the oxytocin peak that would otherwise occur at the time of birth because the stretching receptors of a woman’s lower vagina (which trigger the peak) are numbed.
As Dr. Sarah Buckley explains 1:
A woman laboring with an epidural therefore misses out on the final powerful contractions of labor and must use her own effort, often against gravity, to compensate for this loss. This explains the increased length of the second stage of labor and the increased need for forceps when an epidural is used.
Epidurals have also been shown to inhibit catecholamine (CA) production. Remember that CA can slow or stop labor in the early stages, but it promotes the fetus ejection reflex in the second stage of labor. Thus inhibiting CA production may make delivery more difficult.
Epidurals limit release of prostaglandin F2 alpha, a lipid compound that stimulates uterine contractions and is thought to be involved with the initiation of labor. Prostaglandin F2 alpha levels should naturally rise during an undisturbed labor. However, in one study women with epidurals experienced a decrease in PGF2 alpha and a consequent increase in labor times from 4.7 to 7.8 hours.
Epidurals interfere with labor and have side effects for mothers
Epidurals have been shown to have the following effects on labor and laboring mothers:
They lengthen labor.
They triple the risk of severe perineal tear.
They may increase the risk of cesarean section by 2.5 times.
They triple the occurrence of induction with synthetic oxytocin (Pitocin).
They quadruple the chances a baby will be persistently posterior (POP, face up) in the final stages of labor, which in turn decreases the chances of spontaneous vaginal birth (see below).
They decrease the chances of spontaneous vaginal delivery. In 6 of 9 studies reviewed in one analysis, less than half of women who received an epidural had a spontaneous vaginal delivery.
They increase the chances of complications from instrumental delivery. When women with an epidural had a forceps delivery, the amount of force used by the clinician was almost double that used when an epidural was not in place. This is significant because instrumental deliveries can increase the short-term risks of bruising, facial injuries, displacement of skull bones and blood clots in the scalp for babies, and of episiotomy and tears to the vagina and perineum in mothers.
They increase the risk of pelvic floor problems (urinary, anal and sexual disorders) in mothers after birth, which rarely resolve spontaneously.
One important thing to note about these studies: in most of them, the women in the “control” groups were given opiate painkillers, which are also known to disrupt the natural hormonal processes of birth. We can assume, then, that a comparison of women using no drugs during labor would have revealed even more substantial differences.
Epidural also have side effects for babies
It’s important to understand that drugs administered by epidural enter the baby’s bloodstream at equal and sometimes even higher levels than those present in the mother’s bloodstream.
However, because babies’ immune systems are immature, it takes longer for them to eliminate epidural drugs. For example, the half-life of bupivacaine, a commonly used epidural analgesic, is 2.7 hours in an adult but close to 8 hours in a newborn. 2
Studies have found detectable amounts of bupivacain metabolites in the urine of exposed newborns for 36 hours following spinal anesthesia for cesarians.
Some studies have found deficits in newborn abilities that are consistent with the known toxicity of drugs used in epidurals.
Other studies have found that local anesthetics used in epidurals may adversely effect the newborn immune system, possibly by activating the stress response.
There is evidence that epidurals can compromise fetal blood and oxygen supply, probably via the decrease in maternal blood pressure that epidurals are known to cause.
Epidurals have been shown to cause fetal bradycardia, a decrease in the fetal heart rate (FHR). This is probably secondary to the decrease in maternal CA caused by epidurals which in turn leads to low blood pressure and uterine hyper-stimulation.
Epidurals can cause maternal fever, which in turn may affect the baby. In a large study of first-time moms, babies born to mothers with fever (97% of whom had epidurals) were more likely to be in poor condition (low APGAR scores) at birth, to have poor tone, to require resuscitation and to have seizures in the newborn period, compared to babies born to mothers without fever.
Older studies using the more exacting Brazelton Neonatal Behavioral Assessment Scale (NBAS, devised by pediatricians) rather than the newer, highly criticized Neurologic and Adaptive Capacity Score (NACS, devised by anesthesiologists – can you say “conflict of interest”?) found significant neurobehavioral effects in babies exposed to epidurals.
In one such study, researchers found less alertness and ability to orient, and less mature motor abilities, for the first month of life. These findings were in proportion to the dose of bupivacaine administered, suggesting a dose-related response.
Epidurals may interfere with mother-baby bonding and breastfeeding
Some studies suggest that epidurals may interfere with the normal bonding that occurs between mothers and babies just after birth.
In one study, mothers given epidurals spent less time with their babies in the hospital. The higher doses of drugs they received, the less time they spent.
In another study, mothers who had epidurals described their babies as more difficult to care for one month later than mothers who hadn’t had an epidural.
It’s important to note that neither of these studies prove that epidurals were the cause of the behavioral changes observed. However, if epidurals were at fault, the effects are most likely caused by their interference with the natural orchestration of hormones we discussed in the previous post, and may also be influenced by drug toxicity and the complications associated with epidural births: long labors, forceps and cesareans.
There is also evidence that epidurals may decrease breastfeeding efficiency.
In one study, researchers used the Infant Breastfeeding Assessment Tool (IBFAT) and found scores highest amongst unmedicated babies, lower for babies exposed to epidurals and IV opiates, and lowest for babies exposed to both.
A large prospective study found that women who had used epidurals were more than 2 times as likely to have stopped breastfeeding by 24 weeks compared with women who used non-pharmacological pain relief.
Epidural analgesia is a highly effective form of pain relief and a useful intervention in certain circumstances.
However, epidurals and spinals also cause unintended side effects in both the mother and baby, and interfere with the natural birth process and bonding between mother & baby.
In some cases epidurals may be beneficial, but the evidence suggests that they should not be used as routinely as they currently are in the U.S. and other industrialized countries.