No medication is 100% safe. Not Tylenol, not Paxil, and not an epidural. Everything has a potential side effect, risk, drug interaction - and it doesn't just depend on your body chemistry, some chemicals are just plain not healthy.

Just because it's 'approved' by the FDA, people like it, it's available on the shelf, or it's used very often does not automatically mean it is safe. Pain medication for labour is the most common intervention used, offered, and sometimes even forced on a pregnant woman. They come in many varieties:

Caudal anesthesia, Pudendal block, epidural block, Demerol/Pethidine (a derivative of morphine), Spinal Block, Gas & Air (Entonox), Sparine and chloral - to name a few.

You may be told there are minimal, almost nonexistent risks, and the benefits outweigh any that could possibly come up. Drugs are pushed on mothers so heavily that many women choose to invite friends, or hire birth assistants specifically for the purpose of heeding off any 'friendly' nurses wielding needles. During the transition phase of labour, many women experience contractions that make them feel 'out of control', during which time many women will think about (ask for, scream for, threaten murder over) drugs. This is normal, and it passes. Unfortunately, nurses may be standing by waiting for these moments, and take advantage of them by offering drugs to prevent 'martyr birth', or remind you that drugs are safe, effective and everyone does them.

These are some of the risks, and facts about medication that you may not be told.

Epidural:
An epidural anesthesia is the most common type of pain relief chosen by labouring women. A local anesthetic is administered to the lower back, and then a very long needle is inserted into the spine which makes a hole that a catheter is threaded into. The needle is removed, and the catheter taped to your skin. Doses of pain relief are then filtered through the catheter. This process takes about twenty minutes to complete, during which the mother must remain still. The drug takes another 10-20 minutes to kick in. This link informatively outlines the risks associated with an epidural, and provides information on how to avoid them. These risks include: increased rate of cesarean section, loss of sexual function, prolonged labour, fever, and even a risk of abnormal heart rate and poor muscle tone in the new baby. Epidural can also inhibit a baby's suckling instinct, and decrease the sucking reflex, which can significantly impact the breastfeeding relationship. As many women can attest, just one bottle can make it or break it for some babies.
'Epidural Misadventures' is "A review of the risk and complications associated with epidural anesthesia", and was written by a doctor in Halifax. The article is a lot more informative and dry than the title suggestions.
Medical Risks of an Epidural Anesthesia During Childbirth is still under construction, but only because there is so much information to gather. Despite the warning of being 'unfinished', the information available and the research referenced is complete enough for a lot of reading. And finally, " Epidural: Real risks for mother and Baby".

Demerol/Pethidine:
Otherwise known as 'meperidine hydrochloride', or pethidine, the drug is similar to morphine and heroin. Pethidine is an opiate, and a depressant, it is claimed to work by mimicking endorphins. It is interesting to note that this drug is unrated, and not advised for use during pregnancy. Pethidine is administered via an intra-muscular shot usually into the thigh or buttock but occasionally is given via an IV drip, and has been used since the 1940's. The drug takes between 10 and 20 minutes to begin working when administered by a shot, and only a few moments when given through an IV. It lasts between two and three hours by shot, but wears off much quicker through the IV. Studies have shown it to be highly ineffective, in fact 48% of women said it gave them no pain relief at all, and 60% of women who took it asked for an epidural later. Even though the drug has been shown not to inhibit pain, the doses are high enough to have an effect on the baby, including significantly impaired motor ability. Half of the infants exposed to it failed to breastfeed - this effect can last days. Pethidine crosses the placenta and comes into the milk, because it is a depressant it has an effect on the baby's respiratory center, the effects are the worst if the baby is born within two to three hours after the injection. An antidote can be given to the baby to reverse the effects, however the antidote wears off quickly and the breathing and motor problems can come back, also long term effects of the antidote have not been studied. Babies whose mothers had pethidine are also more likely to develop jaundice, or require neonatal care and be separated from the mother for long periods of time. As with any narcotic pain relief, children exposed to it are more likely to become drug-addicted in adulthood, one study cites that they instance is 4.7 times higher. Babies exposed to pethidine also showed a greater difficulty in quieting once they became upset, this was still noted three, and six weeks postpartum.
For more information on pethidine, visit "Pethidine - a Little shot of something not so nice", "Drugs in Labour: What effects do they have twenty years hence?". Unfortunately there's not a whole lot of information outlining the risks and/or benefits of pethidine or demerol so my links for this one are lacking.

Entonox:
Entonox, otherwise known as "gas and air" or nitrous oxide (laughing gas) is the most common pain medication used by midwives for their patients, one of two pain medications that can be taken into a home birth setting, and is much less often used in hospital birth. It is self-administered by way of breathing through a mask or mouthpiece attached to a portable canister, or constant source (like those with oxygen in many hospitals). The gas has a sweetish taste, and needs a few fast, deep inhalations to speed up the initial pain relief. A distinct flowing sound can be heard when breathing correctly. Relief can be felt as quickly as twenty seconds, and as long as two minutes, but it only takes fifteen seconds for the nitrous oxide to reach your brain from your lungs.
Contraindications for entonox during labour are few and far between, it is one of the least dangerous pain 'medications' used, however it is also one of the least effective (next to demerol), one half of women who were given entonox reported significant pain relief. It is out of the bloodstream in a matter of moments, and is similarly out of the baby once they begin to cry. It does not have an impact on the baby's respiration, ability to suckle or motor functions, however studies have linked entonox use during labour to an increased risk of using amphetamines later in life. Entonox gives a 'high' or 'drunk' feeling, and relief is best felt during early labour. It can effect a woman's ability to push during second stage of labour, and be very dehydrating so water intake should be monitored. Side effects in the mother include dizziness, nausea, vomiting, and poor recollection of labour.
More information on Entonox can be found at, "Royal North Shore Pain Site" or the Pregnancy.com information section on nitrous oxide. Like Demerol, the information on entonox is lacking but this is mostly due to the fact that it is so rarely used in North America.

There are many alternatives to a medicated birth, including natural forms of pain-control that your caregiver may not discuss with you.
Water birth is also called an 'aquadural' for it's amazing pain-relief qualities; floating in a tub of water takes the pressure off your hips and back, it can take the 'back' out of back labour, allow you to change positions easily and comfortably, help you focus and remain calm. Studies have shown that in first time mothers, labouring in the water reduces the want for pain medication by half. Waterbirthing also significantly reduces the risk of tearing, or a need for an episiotomy.
More information on Water Birthing can be found at "WaterBirth International" and "The Water Birth Website" and "Water Birth (a large collection of links, books, pamphlets and other information)" and "Waterbirth Babies May be Healthier"

Hypnobirthing is an option that is rarely heard about. A common misconception is that in order to practice hypnobirthing you must be hypnotized by someone, the way we envision an audience member coming up on stage to the Great Gambino with a swirly coin. Hypnobirthing is defined as 'focused concentration', you've probably hypnotized yourself this way on many occasions and not recognized it. It is a natural response to pain, and for some it comes very easily. Some people are not susceptible to hypnosis, but it's not as many as you'd think: around 95% of the population can be successfully hypnotized, but a lot has to do with your willingness and belief. Classes and private instructors are available in many locations. Hypnobirth can be one of the most effective forms of pain relief you can try, it boasts a high success rate in reducing pain to "manageable", "pressure", "None until transition" and even "none at all". Yes, women have actually given birth without a bit of pain as a result of successful hypnobirthing. For more information on hypnobirthing, check out "HypnoBabies",

TENS (Transcutaneous Electrical Nerve Stimulation) machines are available for use at most alternative medicine, physiotherapy or chiropractic clinics. If you've ever had back pain, you may have had one used on you. Four small pads are placed at key points on your body, and when the machine is turned on you'll feel a pulsing sensation as it stimulates your nerves to produce more endorphins; the natural pain relief within your body.
You can find out more information on TENS at "MidwifeInfo", "Spine Inc." and even rent a machine from the "BabyCare TENS" website!

If you are curious, like to be informed or feel passionately (and even if you don't) I highly recommend reading articles about childbirth interventions and collections of information like the ones found Here (Evaluated Childbirth: Interventions), or here (Childbirth interventions). For a more intimate look at the effects (both physical and psychological) of interventions of all kinds, you may want to read an article called "The Rape of the 20th Century", I will give a warning of it's intensity though.

Part II: Doulas, Homebirth and other birth options.