These obstetrical injuries to the anal sphincter increase the risk of anal incontinence during a woman’s postreproductive years. It’s been reported that just over 40 percent of women with anal sphincter disruption during childbirth will have temporary anal incontinence after delivery, and that 7 percent will experience permanent loss of anal control to some degree.
To safeguard sexual function. What about the bedroom? While the long-term impact of episiotomy on sexual function is unknown, a 1994 study found sexual satisfaction at three months postpartum to be greatest among women without perineal injury. Satisfaction was lowest among women with an episiotomy that had extended, or torn further, during delivery.
TWO TYPES OF EPISIOTOMY: WHICH ONE IS BEST?
There are two basic types of episiotomies.
A median episiotomy is cut right down the center of the perineum, between the vagina and the rectum.
A mediolateral episiotomy is angled off to the side, into either the right or the left labial area.
Two types of episiotomy—median and mediolateral
Which type of episiotomy is preferable if you have to choose? Median episiotomies have been associated with less postpartum and sexual pain, less blood loss, and a lower risk of infection. However, because it’s positioned right down the middle, the median approach confers a very substantial risk of tearing into the anal opening or rectum, somewhere between 11 and 12 percent. Mediolateral episiotomies are associated with more postpartum and sexual pain and possibly more muscle weakness, but they generally decrease the risk of anal or rectal injury to around 1 to 2 percent.
There are pros and cons to both types, and there is no obvious right choice that applies to all women. For women with a short perineum—meaning the distance between vagina and rectum is very small—a mediolateral might best help to avoid extension of the episiotomy into the anal sphincter. With a long perineum, a median episiotomy might help to avoid tearing into the labia. Median episiotomies are more popular in North America, whereas mediolateral episiotomies have remained more popular in Europe, and doctors from both sides of the ocean have long debated which method is less traumatic. Unfortunately, despite the fact that these procedures involve their most intimate parts, women have rarely been invited to join the debate.
“Wait a second,” I can hear you asking, “aren’t episiotomies, and all of these associated injuries, repaired before leaving the labor room?” Isn’t everything put back into place after delivery, allowing you to eventually heal back to full strength? Though you might assume so, the data argues otherwise. First of all, it’s been found using ultrasound that even after repair of a torn anal sphincter right after delivery, separated anal muscles are still seen in up to 40 percent of these women postpartum. Secondly, according to a survey of obstetricians in the United Kingdom, less than a third of doctors reported that they felt adequately trained in repairing anal sphincter injuries that occur during childbirth.
As the problem of anal incontinence has begun to earn its long-overdue place on the women’s health-care agenda, debate has increased regarding the best techniques for repairing perineal and anal injuries in the delivery room. Some expert surgeons specializing in obstetrical anal sphincter injury have recently begun to advocate a more meticulous surgical approach in the labor room, using overlapping repair techniques that attach the torn muscles more strongly. In the short term, this method has been reported to lower the risk of anal incontinence, but overlapping sphincter repair is not yet included in most general obstetrical training; nor has it been proven to be the best technique over the long run. As the problem of anal incontinence continues to be addressed, you’ll undoubtedly see greater efforts being made to prevent and repair these injuries in the delivery room, whether with the overlapping repair or other innovations. For now, reducing the number of unnecessary episiotomies in our obstetrical world would probably do the most good.
When an episiotomy is avoidable, avoid it!
WHEN SHOULD YOU HAVE AN EPISIOTOMY?
Physicians trained in recent years tend to favor a relatively hands-off approach when it comes to episiotomies, compared to their predecessors, who tended to intervene with less hesitation. But even today, there are a handful of absolutely, positively justified reasons for your doctor or midwife to cut an episiotomy. For instance:
In cases of fetal distress or an abnormal fetal heart rate close to delivery, a well-timed episiotomy can shorten the time to delivery by critical minutes.
If the baby becomes stuck during delivery—particularly if the shoulders are wedged behind the pubic bone (shoulder dystocia)—an immediate episiotomy is warranted to help prevent asphyxiation of the newborn.
Sometimes an obstetrician will notice a particularly severe injury occurring in some place other than the perineum—for example, the labia, urethra, or clitoral area—and perform an episiotomy to relieve pressure and spare extensive injury that can be both painful and difficult to repair.
Clinicians would routinely include an episiotomy with each forceps or vacuum (a soft suction device used to gently pull the fetal head toward the vaginal opening) delivery, creating more room for inserting these devices. However, most physicians have abandoned the routine use of episiotomy even during these operative deliveries, using them on a more selective basis.
If you have an episiotomy, the overwhelming odds predict that you’ll do absolutely fine. But if your doctor or midwife recommends planning an episiotomy with the intent of protecting your body from injury, then it’s time to ask some questions and perhaps explore your provider’s style. According to some specialists in obstetrical injury, the most appropriate episiotomy rate should be no higher than around 20 to 30 percent for uncomplicated pregnancies. Recent trends are encouraging in this regard; one review of more than thirty-four thousand vaginal deliveries found a decline in episiotomy rate from 69.6 percent of all vaginal births in 1983 to 19.4 percent in 2000. Episiotomies will always have an important place in the labor room, but today’s research says there’s little basis for routinely cutting one in order to preserve your pelvic floor.
EPISIOTOMY: JUST THE TIP OF THE ICEBERG OF PELVIC CHANGE
In the end, episiotomies probably carry as much symbolic and emotional weight as actual medical importance. Injury to the perineum is just the tip of the iceberg of pelvic injury that can result from childbirth—the surface damage that, however significant, is often small compared with the more extensive, deeper changes that occur at its base. Before reaching the perineum, the fetus has traversed the foundation of your pelvic supports and a number of structures that will determine your postreproductive function and control. Sometimes the most important damage has already been inflicted, completely unseen.
It’s time for you, the central person in the labor room, to familiarize yourself with the parts of your body hidden beneath the iceberg’s tip. Let’s continue unfolding the anatomy of labor and take a look at the unseen structures that are essential to your health, independence, and intimacy beyond the labor room. A little knowledge can empower you to prevent future problems and alleviate those you might already have.
Muscle and Nerve Injury: Changes to the Iceberg’s Base
THE LEVATOR MUSCLES AFTER CHILDBIRTH
If you developed prolapse or incontinence any time during your postreproductive years—even decades later—it’s likely that the seeds of your problem were silently planted when the levator muscles (remember, the foundation of your pelvic-floor supports) stretched, separated, or weakened at the time of vaginal delivery. Injury to the levator muscles and their accompanying nerves may be one of the most problematic changes that can occur to your lower body during childbirth.
Levator changes after childbirth may take a few different forms. The levator muscle shelf may start to drop, leaving the pelvic organs supported only by the much weaker connective tissues, which often begin to stretch beneath the burden. With levator injury, the iceberg of pelvic support weakens at its base, and the chain of events leading to prolapse an
d other pelvic-floor problems begins.
If the sling portions of the levator muscles encircling the urethral and anal areas are torn during delivery, the sphincters may fail to instantly tighten during a cough or sneeze. This may spell incontinence over time.
You can improve the strength and function of your levator muscles using exercises and a variety of pelvic-floor treatments. Even if you don’t rebuild the full strength of your pelvic-floor foundation, you can often make enough progress to restore your control and relieve your postreproductive symptoms. In Appendix A, you’ll learn the best techniques for rehabilitating your pelvic floor.
The levator ani muscles are the elevator for the pelvis, keeping the female pelvic organs lifted and preventing prolapse and incontinence. Improving these muscles’ strength and function is a major strategy for treating a number of postreproductive problems.
The Importance of Nerve Injury During Childbirth
Time for the million-dollar question: can you name the type of nerve injury you’re most likely to experience during your lifetime? Here’s a quick clue—it’s not a pinched nerve in your neck, and it’s not carpal tunnel syndrome in the wrist. No, it’s injury to the pelvic nerves during pregnancy and childbirth, which may represent the most likely instance of nerve damage during a woman’s lifetime; it’s seen in up to 15 percent of women after delivery. Though many women will never feel any symptoms, others will experience incontinence, prolapse, or other pelvic-floor disorders later on.
But why all the fuss over nerve injury if we just learned that changes to the muscles are the cause of prolapse and incontinence? The reason is that injuries to nerves and muscle are closely related. Have you ever crossed your legs for too long to find your foot has fallen asleep? Or have you watched a movie with your spouse lying across your arm, then stood to find that the muscles in your arm felt completely dead for a minute or two? In both cases, you’ve compressed a major nerve where it was exposed and vulnerable to external pressure—behind the knee and inside the upper arm. What you’ve felt temporarily are the effects of this nerve compression on neighboring muscles. Fortunately, in both of these cases, the nerve compression was mild and brief, so its effect on the nearby muscles lasted only a short time.
When a nerve is injured for longer periods of time, however, the muscle groups at its end begin a more permanent process of weakening, or atrophy. Examples of muscle atrophy following nerve injury can be found all over the body—for instance, in the facial droop of a stroke patient or in the thinned legs of a paraplegic. In these cases, damage to a nerve supply acts like snipping the roots of a plant: the nearby muscles, like flowers, begin to wilt.
THE PELVIC NERVES, FROM A BRAND-NEW, FEMALE POINT OF VIEW
Surprised that you’ve never heard about nerve injury as an important feature of childbirth? You should be. After all, urologists counsel their male patients at length regarding the risks of nerve injury and erectile dysfunction accompanying prostate surgery. Shouldn’t women understand, in a basic way, how certain choices surrounding childbirth might influence the long-term health of their pelvic nerves? Although childbirth is a natural life-cycle event, not a disease, you’re no less entitled to be informed of the effects of obstetrical procedures.
PUDENDAL NERVE INJURY AND LEVATOR ATROPHY
As previously mentioned, you’ll find your most important pelvic nerves—the pudendals—on either side of your pelvis’s inside walls. Stretching and compression of the pudendal can occur as the fetus passes through the pelvis. But how and when? The nerves may be most exposed and vulnerable to injury where they pass a prominent protuberance of bone called the ischial spine, located on either side of your inner pelvis. There, the pudendal can be directly compressed by anything trying to squeeze its way through. Imagine those remarkable forces generated between the fetal head and maternal pelvis during maternal pushing, applied right onto a nerve that’s roughly the size and strength of a spaghetti noodle cooked al dente. Then imagine the same nerve getting caught between the metal edge of a forceps blade and the solid bone of the pelvic wall.
Nearly 20 percent of normal vaginal deliveries are associated with pudendal injury afterward, and a significant number persist over the long term; forceps deliveries increase your risk of pelvic nerve injury by 40 to 60 percent. Long labors, large babies, and multiple deliveries have also been linked to diminished nerve function. Remarkably, two separate studies showed that cesarean delivery—when performed before labor begins—tends to preserve normal nerve function.
What are the consequences of pudendal nerve injury? Injury to the pudendal nerve might be the common-denominator obstetrical event leading to some of the more typical postreproductive problems after vaginal childbirth. Compression and stretching of this key nerve begin the process of muscle weakness, leading to wilting of the shelf and sling levator supports. If pelvic-nerve injury occurs—even if you have no symptoms right after childbirth—you still may be at significant risk for developing prolapse, urinary and anal incontinence, and other pelvic symptoms over time.
Now you can see why labor and delivery might be the most likely cause of nerve damage in women, and how nerve injury in the pelvis is a crucial and often overlooked aspect of your postreproductive health and control. Whether it’s the pudendal nerve or other nearby pelvic nerves that are most vital for your future function remains an ongoing scientific question. Regardless, the rather unsettling reality remains the same: many pelvic nerve and muscle injuries occur relatively early in labor, long before the events commanding most of our attention, episiotomies and perineal injuries.
Compression of the pudendal nerve between the fetal head and the pelvic bones during labor
Connective-Tissue Injuries
After childbirth virtually every woman has some degree of injury to her pelvic connective tissues—that fibrous support layer surrounding the pelvic organs and helping attach them to the bony pelvis. Why is that? First of all, their location leaves them vulnerable to injury during childbirth. The pelvic connective tissues are a major component of the vagina, enveloping its walls and attaching the vaginal tube to the pelvic sidewalls. As a result, when the vagina stretches, the connective tissues are placed under tremendous strain. Second, the pelvic connective tissues are prone to permanent injury, rather than temporary strain, because they are not very elastic. They’re less able than muscle to stretch and then return to their original shape, so they do poorly with the physical stress of childbirth and afterward, when the physical strain of daily activity and exertion creates further wear and tear.
What is the significance of connective-tissue injury? As mentioned in chapter 2, the connective tissues do not provide the main foundation for the pelvic organs, but they do play an important secondary role. Particularly for women whose levator muscles (the nails and screws of pelvic support) weaken after childbirth, the connective tissues (the carpenter’s glue of the pelvis) help to maintain the positions of the bladder, bowel, and vagina. If these connective-tissue supports of the pelvis also give way, there’s nothing left to prevent pelvic prolapse and incontinence in their various forms.
Weakening of the connective tissues:
Between the bladder and vagina causes a cystocele.
Between the rectum and vagina causes a rectocele.
Between the uterus and pelvis causes uterine prolapse.
At the top of vagina causes an enterocele.
Around the urethra can lead to urinary stress incontinence.
Your Bladder During Pregnancy
A landmark 1960 study showed that while around 18 percent of women experienced some incontinence before pregnancy, over 50 percent had complaints by their third trimester. Since then, other studies have confirmed that incontinence symptoms reach a peak around thirty-eight weeks. So even if you’ve never leaked, or have never given birth, pregnancy alone can be enough to cause urinary stress incontinence. If you’ve had some stress incontinence before pregnancy, the odds are that your symptoms will get worse during those nine
months. But why?
First, the uterus is located right next to the bladder and urethra. As your baby grows and the uterus expands during pregnancy, pressure on these nearby structures slowly but surely increases. The most obvious symptom resulting from this pelvic space crunch is the frequent need to urinate, as your bladder, with limited room to expand, begins to feel full with less and less fluid inside. Eventually, as the fetal head drops into the pelvis, your bladder’s capacity becomes just a fraction of what it was before pregnancy. That’s one reason, along with an overall increase in urine produced, why most women are constantly running to the women’s room during those last few months before delivery.
But beyond this inconvenience, could permanent problems result from this constant pressure on the urethra, bladder, and nearby vaginal supports? For some of you, the answer is yes. Through stretching and injury to the nearby muscles, connective tissues, and pelvic nerves the prolonged force of a pregnant uterus can cause a number of lasting changes to bladder function, including the floppy urethra and the thin-walled urethra.
Ever Since I Had My Baby Page 6