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Table of Contents
Introduction
Chapter 7: The Slow Labor
Chapter 7: Literature Summaries
Resources
How to Order
Thinking Woman’s Home
Obstetric Myths Home
© 1999 by Perigee Books
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 The Thinking Woman’s Guide to a Better Birth
Chapter 7 The Slow Labor: Patience Is a Virtue
1. Problems with Typical Management
a. Active Management of Labor
b. Procedures
2. The Bottom Line
a. Benefits and Risks of Techniques
for Coping with Poor Progress
b. Strategies to Avoid the Need for IV Oxytocin,
Instrumental Delivery or Cesarean Section
3. Gleanings from the Medical Literature and Bibliography
Obstetricians treat women laboring slowly the way Peter Pan treated the Lost Boys. He expected everyone to adapt to his ideas of the way things should be. If they didn’t, Peter saw to it that they did. For example, the boys entered the Neverland underground home through hollow trees. If a boy didn’t fit his tree, James Barrie writes, Peter “did something” to the boy. So too with obstetric management. Obstetricians have inflexible ideas of how labor ought to go. If your labor doesn’t conform to that pattern, typical doctors “do something” to you to make you fit. There are, as you may gather, a number of drawbacks to this myopic approach.
The first is that the standard for labor progress doesn’t give you nearly enough time before you are declared over the line. Doctors base their standard on studies from the 1950s and 60s supposedly of normal labors, but many women had interventions that could shorten labor such as oxytocin (trade name: Pitocin or “Pit”) or forceps delivery. A recent study evaluating healthy women who had no interventions that would affect labor length got very different results. For example, the standard says that starting from 4 centimeters cervical dilation, the average first-time mother will take 6 hours to achieve full dilation of 10 centimeters. Doctors set the cutoff defining “abnormal” progress in dilation at 12 hours for first-time mothers and 6 hours for women with previous births because, according to the standard-setting studies, only 5% of women will take longer than this. However, the new study found that average duration in first-time mothers was 7 1/2 hours, not 6, and the threshold for abnormal, fell at 19 1/2 hours, not 12, in first-time mothers and over 13 1/2 hours, not 6, in women with prior births. The standard also stipulates smooth, linear progress. More than a relatively brief halt is thought to require action. However, averaging many labors together evens out the variations. Individual labors often don’t work this way.
A second drawback is that obstetric management can obstruct progress. Epidural anesthesia is a notable example of this. Confinement to bed and pushing while lying on one’s back may also interfere. Refraining from these things would seem obvious, but mainstream obstetricians rarely recognize their management as the problem. Within the obstetric mindset, all labor difficulties originate in the woman or her baby. Doctors are always the “fixers,” never the “breakers.”
Finally, doctors have few ideas about what to do. They can rupture membranes, which is supposed to speed things up, although that is debatable (see page 000). They can strengthen contractions by giving IV oxytocin, or they can deliver the baby via vacuum extraction, forceps, or cesarean section. This limited repertoire has its own drawbacks.
To begin with, weak contractions are only one of several reasons why labor progress may be slow or come to what is in most cases a temporary halt. To cite three:
 The baby may be in the occiput posterior position, a hidden factor in as many as half of all cesareans for poor progress. In the posterior position, the back of the baby’s head (occiput) is towards the mothers back. During labor with a baby in the favorable anterior position, contractions push the rounded crown of the baby’s head downward against the cervix, which helps open it. However, the posterior baby cant help because the cervix lies against the broad middle of the baby’s head. (Think of it like trying to pull on a tight turtleneck sweater.) In addition, most posterior babies cannot fit through their mothers pelvis without swiveling to anterior.
Sometimes in early labor the cervix, the neck-like opening of the uterus, impedes progress. During pregnancy, the cervixs job is to keep the baby in against the pull of gravity. In preparation for labor and during early labor, the firm connective tissue in the cervix softens like a dry sponge absorbing water, the cervix shifts forward so as to be in line with the force of contractions, and it effaces, meaning it draws up into the body of the uterus (see drawing). If the cervix has not finished this process, dilation will proceed slowly if at all.
Fear, anxiety, and other psychological issues can also hold up labor.
If weak contractions aren’t the problem, oxytocin isn’t the answer.
In addition, rupturing membranes, IV oxytocin, vacuum extraction, forceps delivery, and cesarean section can pose serious risks to baby or mother. These interventions should be the last, not the first–let alone the only–resorts, but, unlike most midwives, many doctors don’t know any alternatives.
As a result of obstetric impatience and injudicious management, in 1995, about one in five U.S. women who began labor on their own had oxytocin stimulation (augmentation), and nearly 176,000 women had cesareans for failure to progress, prolonged labor, labor dystocia (dysfunctional labor), or cephalopelvic disproportion (the baby didn’t fit). These diagnoses are all ways of saying the baby didn’t come out within somebodys idea of a reasonable time, but “reasonable” is primarily a matter of philosophy, not physiology, as the enormous variation in the rates of oxytocin use and instrumental and cesarean delivery among caregivers attests. As one editorialist all too aptly put it, “Unfortunately, we have spent the last 25 years managing labour without knowing what we do.”
Active Management of Labor
Doctors think they have at last found a way to make labor adhere to their pattern. In recent years active management of labor has swept the English-speaking obstetric world. From the obstetric viewpoint, it has everything to recommend it. Its rigid, precise protocol sounds reassuringly scientific. It is supposed to eliminate cesareans for poor progress even in the face of epidurals, which slow labor down. And best of all, it allows doctors to orchestrate every contraction. However, nothing about active management is as it seems except the control.
Active management of labor came out of the Dublin, Ireland National Maternity Hospital in the 1970s. According to its developers, it was intended to benefit first-time mothers by preventing prolonged labor. Obstetricians guaranteed that women would not labor for more than 12 hours, that is, 10 hours to dilate and 2 to push out the baby, this being the maximal labor length they thought women could tolerate without pain medication. (They never asked women what they thought, though; several studies have shown that women don’t like oxytocin because it makes contractions hurt more. Whatever the Dublin doctors believed their reasons for active managment were, their book, Active Management of Labor, reveals who active management really benefits: it spares obstetricians the “tedious hours” of waiting until full cervical dilation, and it transforms the “previously haphazard approach” to planning for staffing.
Active management attracted attention outside Ireland because in an era where cesarean rates in many countries–including the U.S–were skyrocketing, the National Maternity Hospital cesarean rate remained stable at about 5% without any apparent disadvantage in maternal and newborn outcomes. Active management was not responsible, however. The cesarean rate was even lower before its introduction.
The cornerstone of active management is to rupture membranes once labor is established and give any first-time mother who fails to dilate at 1 centimeter or more per hour IV oxytocin. It begins at dosages considerably above blood levels produced naturally and ends with dosages that are twice the amount that are permitted in protocols that mimic normal oxytocin levels. The active management oxytocin regimen may seem scientifically precise, but it was not based on any experimental data, and its rationales had nothing to do with science. For example, the Dublin doctors linked the drip rate strictly to contraction frequency to prevent soft-hearted midwives from turning down the drip rate when women complained of the pain. Indeed, the doctors of the National Maternity Hospital state in their book that the laboring womans job in this scheme of “military efficiency” with a “human face” is to take orders and not to disturb the labor unit by making “the degrading scenes that occasionally result from the failure of a woman to fulfill her part of the contract.”
Does active management work? Yes and no. It does tend to shorten labor compared with lower-dose oxytocin regimens, and a few studies have shown it reduces the cesarean rate, although others do not. All this means, though, is that if more women can be forced to fit their doctors unrealistic expectations of labor duration–forced to “fit their Neverland tree”, so to speak–their doctors may operate less often.
Also, some of the components that almost certainly contribute to reducing the odds of cesarean for poor progress didn’t make the trans-Atlantic crossing. The Dublin protocol mandates a trained woman who never leaves the laboring woman’s side. A body of research attests to the benefits of this practice. According to the protocol, women will not be admitted to the labor unit unless they are in progressive labor with effaced cervixes. By contrast, U.S. hospitals frequently admit women in very early labor or who are having prelabor contractions.* Because progress is normally slow in early labor and nil if the mother isn’t in labor, early admission plus impatience often equals unnecessary intervention. As originally conceived, active management assumed a minimal use of epidurals. The Dublin obstetricians believed that the promise of a 12-hour or less labor length would enable women to get through labor without pain medication, another thing they surely didn’t consult women about. Epidurals increase the cesarean rate for poor progress even when doctors practice active managment.
Active management also has serious drawbacks. First-time mothers are given oxytocin if they don’t steadily progress at the average rate–a rate that is probably an underestimate. At one stroke, deviation from the average has been defined as abnormal. Studies have shown that with active management, 40% or more of first-time mothers will receive oxytocin. Telling nearly half of laboring first-time mothers their bodies are incapable of birthing a baby without help could have significant psychological consequences. For example, the use of labor interventions, not surprisingly, links to postpartum depression. And high-dose oxytocin increases the chances of overly long, overly strong contractions, which, by depriving the baby of oxygen, can cause fetal distress and worse. Setting arbitrary time limits on the pushing phase of labor can also lead to unnecessary and potentially risky procedures. In a study of 13,000 labors at the Dublin National Maternity Hospital, the authors reported that three babies delivered by forceps for prolonged pushing phase died of forceps injuries. In this country, doctors generally don’t use forceps unless the head is low enough to make forceps relatively safe. However, faced with a “time’s up” situation, they would do a cesarean instead–not exactly an improvement!
The sad thing about these disadvantages is that active management isn’t necessary. Numerous studies have demonstrated that other, less aggressive, regimens work just as well. This, however, begs the real question, which is, “Do you need universal amniotomy and liberal use of oxytocin at all?” All studies have compared active managment with standard management. This is like comparing the frying pan to the fire. If active management does better–and it doesn’t always–it’s still the frying pan. Midwives, especially those attending births in free-standing birth centers and homes, have achieved equally low cesarean rates and equally good, if not better, maternal and newborn outcomes with much less use of oxytocin, instrumental delivery, or c-section. In fact, active management makes a good litmus test of whether a practitioner works from the obstetric or midwifery model. If your doctor or midwife thinks its great, head for the door.
Procedures
rupturing membranes (amniotomy): See p. 00.
oxytocin IV: For details of the procedure, see p. 00. There are several schools of thought behind the various oxytocin regimens for strengthening (augmenting) labor. Doctors began using IV oxytocin years before researchers had the technology to study its metabolic properties. Older regimens were based on uterine response: start the drip slowly; turn it up every 15 minutes or so until the mother had what seemed to be three adequate contractions in 10 minutes (the average rate in normal, progressive labor); and turn the drip down if contractions got too strong, long, or close together. This is probably still the most common method used in the U.S. today. Low-dose regimens evolved out of research that determined blood levels during functional labor, how long oxytocin took to metabolize, what dosage rate maintained a steady blood level of oxytocin, and how long it took to produce a maximal response when the dose was increased. Low-dose regimens attempt to imitate the natural process, the goal being to reduce the frequency of adverse effects by minimizing the amount of oxytocin used to bring contractions up to par. Proponents of high-dose regimens such as active management think that giving more oxytocin faster will reduce the number of augmentation failures. High-dose regimens start where low-dose regimens typically end. In addition the interval for judging response and deciding whether to turn up the drip is much shorter than the time actually required for uterine muscle to fully respond.
vacuum extraction: The apparatus consists of a flexible, plastic cap attached to a handle, tubing, and a vacuum source. The doctor uses vacuum to hold the cap to the baby’s head. The doctor then pulls when mother pushes. Vacuum extraction can be used as well to swivel the baby from facing the mothers stomach (posterior) or side (transverse), which is unfavorable for birth, to facing her back (anterior).
forceps delivery: To be used safely, the head must be at least partially through the mothers pelvis. The doctor inserts the curved blades on either side of the baby’s head, locks them together, and pulls. Forceps can also be used to turn the baby from posterior or transverse to anterior.
cesarean section: See p. 00.
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Penny Simkin, noted educator and author, uses “prelabor contractions" instead of “false labor” because there is nothing false about these very real and sometimes painful contractions, and they do eventually lead to progressive labor.
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Continued at The Bottom Line
1. Problems with Typical Management
a. Active Management of Labor
b. Procedures
2. The Bottom Line
a. Benefits and Risks of Techniques for Coping with Poor Progress
b. Strategies to Avoid the Need for IV Oxytocin,
Instrumental Delivery or Cesarean Section
3. Gleanings from the Medical Literature and Bibliography
© 1999 by Perigee Books
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