Epidurals and Birth Injuries

Labor and delivery is an extraordinarily painful experience for women and maternal pain-management has become an important aspect of modern obstetrical practice. The epidural has become the most widely utilized method for managing pain during childbirth and is administered to millions of women in labor every year. Recent estimates suggest that an epidural is given to the mother in over half of all deliveries in the United States and Canada. Seventy-one percent of pregnant women get either an epidural or some other spinal anesthesia. Although epidurals are generally considered safe they do present a number of risks and negative side effects which can potentially increase the risk of complications and related birth injuries. Women have to way the pros and cons of epidurals to make the choice that is best for them.

What is an Epidural?

The epidural is a particular method of administering regional anesthesia that basically numbs the lower half of the mother’s body to block the pain from labor and birth. Anesthetic medication is injected directly into an area of the mother’s spine called the epidural space (which is where the name “epidural” comes from). The epidural space is a fluid filled area which encases the outside of the spinal cord. The body transmits pain signals to the brain through nerve pathways that connect to the spine. Injecting anesthetics into the epidural space is very effective at blocking the transmission of pain signals through these nerve channels.

A single injection of anesthetics into the epidural space is not sufficient to last for the entire labor and delivery. To prevent the medication from wearing off, the anesthesiologist inserts a special type of needle that stays in the mother’s back and is attached to a catheter or drip device. This gives doctors 2 options. They can either use the catheter to administer additional doses of medication as needed; or they can attach the catheter to a pump device which will continuously supply the medication in small amounts. Getting the needle inserted correctly can be difficult and may require several attempts. Epidurals are highly effective at eliminating pain and fewer than 1 out of 100 mothers require additional pain relief after an epidural.

The type of drugs delivered through epidurals are known as local anesthetics, which block pain in targeted areas of the body. The local anesthetic medications most frequently administered with epidurals are: Bupivacaine, Lidocaine, and Chloroprocaine.

Risks and Side Effects of Epidurals

Specific side effects differ somewhat depending on the type of medication used in the epidural. However, there are a number of potential side effects associated with all epidurals:

Lower Blood Pressure: approximately 14% of women who get an epidural experience a sudden drop in blood pressure. Lower blood pressure is not a serious issue but can increase the risk of certain complication and can also cause nausea and discomfort.
Fever: epidurals trigger a fever in around 23% of women who get them. A sudden spike in maternal fever can create serious risks for the baby. A recent study has shown that epidural induced fevers increase the chances of a baby being born with poor muscle tone, breathing issues, and lower Apgar scores.
Urination Problems: because the epidural numbs the lower body it can cause difficulty urinating. About 15% of women experience this side effect which sometimes requires a urinary catheter.

Additional potential risks to the mother presented by epidurals include seizures, heightened risk of infection, respiratory difficulty, and nerve damage. It is not true that epidurals increase the risk of a C-section.

Epidurals Increase the Risk of a Birth Injury

Some studies have shown a link between the use of epidurals and a slightly higher rate of a baby being diagnosed with a birth injury. The reason for this has nothing to do with the medications used in epidurals. Although any drug given to the mother during labor also gets into the baby’s system, the anesthetics used with epidurals do not cause any harm to the baby. The primary reason why getting an epidural creates a somewhat higher risk of a birth injury is that epidurals tend to slow down the birth process. Vaginal delivery of a baby and accomplished through muscle contractions and pushing by the mother. Getting an epidural makes the muscles and lower body go numb making pushing less effective. The effect of an epidural on pushing is comparable to eating or drinking right after the dentist has numbed your mouth for a cavity. You have less sensation and control over the area of the mouth that is numb making it difficult to chew and drink like normal. By numbing the mother’s lower body, an epidural makes it more difficult to efficiently push the baby out.

Anything that prolongs or delays the vaginal childbirth process will automatically increase the potential risk of a birth injury. The process of labor and delivery is highly stressful for the baby. The longer a delivery drags on the more risky it become for the baby. Prolonged labor can subject to the baby to physical distress and creates the risk of oxygen deprivation and brain damage. Moreover, when delivery is not progressing fast enough it might require doctors to intervene and use delivery assistance devices such as forceps or vacuum extractors. When no epidural is given, instrument assisted delivery is necessary less than 10% of the time. However, when the mother gets an epidural the rate of instrument assisted delivery jumps up to 15%. This small increase in the rate of instrument assisted deliveries translates to a significant increase in the risk of birth injury. So while the risk does not jump off the page statistically, it is also silly to suggest that epidurals cannot contribute to birth injuries. The need for mechanical instruments is correlated with birth injuries. If epidurals increase the need for mechanical, it has to follow that they epidurals are the cause of some birth injuries.