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The Slow Labour: Patience is a Virtue

03 Jun

This is a chapter from a book by Henci Goer called The Thinking Woman’s Guide to a Better Birth.  This chapter is on slow labours and inductions.
 

The Thinking Woman’s Guide to a Better Birth
http://hencigoer.com/betterbirth/sample/

Practical Information for a Safe, Satisfying Childbirth

Chapter 7: The Slow Labor: Patience is a Virtue

  1. Problems with Typical Management
    1. Active Management of Labor
    2. Procedures
  2. The Bottom Line
    1. Benefits and Risks of Techniques for Coping With Poor Progress
    2. Strategies to Avoid the Need for IV Oxytocin, Instrumental Delivery or Cesarean Section
  3. Gleanings from the Medical Literature
  4. Bibliography

Problems with Typical Management

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 p.250). 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.103.

oxytocin IV: For details of the procedure, see p.60. 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.21.

  • 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. [Back to text]

The Bottom Line

Benefits and Risks of Techniques for Coping with Poor Progress

Non-Medical Techniques

These include activities such as pelvic rocking or walking, assuming positions such as all-fours or squatting, eating and drinking, massage and acupressure, warm tub baths or showers, and talking.

benefits: Studies suggest that activity and positioning can intensify contractions, bring the baby down, expand the pelvis, * and turn the baby to the favorable anterior position. Eating and drinking can avoid fatigue and dehydration, which may slow labor. Massage, acupressure, and warm tub baths or showers can ease pain and induce relaxation, which may enhance progress. Warm water immersion has been called the “midwives’ epidural.” Talk can provide comfort, reassurance, encouragement, relieve anxiety, and explore what psychological or emotional issues or adverse environmental elements might be affecting labor. Using these strategies as the primary approach avoids unnecessary use of oxytocin, instrumental delivery, and c-section along with their attendant risks.

risks: A full squat may be inadvisable in women with varicose veins or knee joint problems. Women may develop a fever if submerged too deeply for too long in warm water, but this can be alleviated by lifting more of the body out of the water or getting out of the tub, and infection is not a risk with ruptured membranes. As an experiment using a starch-impregnated tampon and iodine in the water proved, bath water does not enter the vagina. Exploration of possible underlying psychological factors may lead a woman to think that slow progress results from not thinking the “right” thoughts, which could lead to self-blame. Contrary to common obstetric belief, eating and drinking in labor pose no risks.

Nipple Stimulation

benefits: Causes secretion of additional oxytocin. Unlike intravenous oxytocin, oxytocin naturally secreted within the brain elevates mood and has amnesiac properties. IV oxytocin cannot cross the blood-brain barrier. Avoids unnecessary use of oxytocin, instrumental delivery, and c-section along with their attendant risks.

risks: May produce overly long, overly strong contractions. Stopping or reducing the stimulation will rapidly normalize contractions.

Amniotomy

Benefits And Risks Of Routine Amniotomy

benefits: Routine early amniotomy shortens labor by an hour or two. It appears to reduce the incidence of 5-minute Apgar scores below 7 but has no other effects on the infant’s condition at birth. It may reduce the use of oxytocin and the number of women who report the most intense degree of labor pain. However, the use of oxytocin, which makes labor more painful, and pain medication, especially epidurals, makes it difficult to determine the relationship between amniotomy and labor pain.

risks: Amniotomy increases the incidence of abnormal fetal heart rate patterns. Studies may underestimate this risk because women not having early amniotomy are more likely to receive oxytocin, which also increases the odds of abnormal fetal heart rate patterns. Routine early amniotomy consistently increases the cesarean rate. When data from seven trials in which women were randomly assigned to early amniotomy or not were analyzed (meta-analysis), women in the early amniotomy group were 20% more likely to have a cesarean. An additional two studies not included in the meta-analysis also reported more cesareans in the early amniotomy group. The percentage found in the meta-analysis may be low because cargivers in several trials were not able to stop doing amniotomies in the “conserve membranes” group. Specifically, half or more of women in the “conserve membranes” group in the two biggest trials had amniotomies, albeit somewhat later in labor. If amniotomy does, in fact, lead to c-section, this would tend to minimize the differences in cesarean rates between the two groups. Early amniotomy may also increase the risk of infection.

Benefits And Risks Of Amniotomy For Indication

benefits: Rupturing membranes may help labor progress, allow closer monitoring when there is concern about the baby, and permit caregivers to determine whether the baby has passed meconium into the amniotic fluid.

risks: Studies suggest that early amniotomy may not benefit slowly progressing labors and that late amniotomy may have unpredictable effects. Valerie El Halta, a prominent home birth midwife, suggests one reason why: if the baby is posterior, that is, facing the mother’s belly instead of her back, labor often progresses slowly until the baby turns into the anterior position. With membrane rupture, the head may surge downward into the pelvis and get stuck. As for permitting closer monitoring for suspected fetal distress, releasing the amniotic fluid adds to the baby’s stress by exposing the umbilical cord to compression during contractions. In addition, one potential cause of fetal distress is that the umbilical cord has slipped between the head and the cervix. Rupturing membranes could then cause prolapse, converting a concerning situation into an emergency.

IV Oxytocin

benefits: Strengthens contractions by increasing circulating oxytocin levels. May avoid the need for instrumental delivery or c-section.

risks: Increases pain. Especially when given in high-dose regimens, oxytocin can produce overly long, overly strong contractions and abnormally high resting uterine-muscle tension, which may deprive the baby of sufficient oxygen. If this is not addressed, it may result in fetal distress (abnormal heart-rate patterns), brain damage, or death. Treatments include reducing or turning off the drip, giving medication to suppress contractions (tocolytics), or if distress continues unabated, cesarean section. With prolonged use, oxytocin increases the risk of postpartum hemorrhage. It may also increase the risk of newborn jaundice. The authors of a recent review of research into oxytocin commented, “If oxytocin had been discovered in the 1990s we would not sanction its widespread routine use and would conduct further clinical trials.”

Vacuum Extraction

benefits: Adds to maternal pushing efforts and can be used to turn the baby from posterior to anterior. Less likely to injure maternal tissues than forceps and may avoid the need for c-section.

risks: Doctors may be more likely to perform an episiotomy, although it is not necessary for this procedure. Episiotomy introduces several maternal risks (see p.155). As for the baby, the vacuum cup may cut the baby’s scalp, although plastic cups are less likely to do this. Vacuum extraction can cause a blood-filled swelling (cephalohematoma) beneath the cup, which increases the likelihood of developing jaundice. Occasionally, profuse bleeding occurs beneath the scalp (subgaleal or subaponeurotic hemorrhage. Unlike the relatively benign cephalohematoma, this bleeding poses a grave risk. Bleeding within the brain is another rare, serious complication. The growing number of reports on serious complications and deaths resulting from vacuum extraction has caused the FDA to issue a warning advisory about this procedure.

Forceps Delivery

benefits: Delivers the baby when the mother cannot accomplish the birth on her own. Forceps can also be used to turn the baby into the favorable anterior position. May avoid the need for c-section.

risks: As typically practiced in the U.S., forceps poses little risk of life-threatening injury to the baby. However, the baby’s face may be cut or bruised, the collar bone broken, or there may be injury, usually temporary, to a nerve complex that controls the arm (brachial plexus injury or Erbs palsy) or to the nerve that controls the facial muscles. Forceps sometimes also cause cephalohematomas. Forceps delivery increases the risk of shoulder dystocia (the shoulders hang up during the birth), which can be life-threatening, but is almost always resolved without incident. Using forceps to rotate the baby 90 or more can cause spinal cord injury. Doctors will almost certainly perform an episiotomy, although it is not always needed, which introduces several maternal risks. Forceps delivery with episiotomy greatly increases the risk of anal tears, which, even though repaired, may permanently weaken the anal sphincter. The forceps may also cut or bruise the vaginal wall. For these reasons, forceps increase the probablility of severe pain in the days after birth.

Cesarean Section

benefits: Deliver the baby when no lesser means will serve, and the baby will be endangered by continuing labor.

risks: While relatively safe as major surgeries go, nonetheless, cesarean section poses considerable risks short-term and long-term to the mother and to any future pregnancies.

Strategies to Avoid the Need for IV Oxytocin, Instrumental Delivery, and Cesarean Section

Have a patient caregiver who sees his or her role as attending your birth not delivering your baby. Sheila Kitzinger, world-famous British author and founder of Britains National Childbirth Trust, says that the most invasive and potentially dangerous technology — because from it proceeds all others — is the clock.

Have your baby at a free-standing birth center or at home. Oxytocin use rates and instrumental and cesarean delivery rates are much lower for out-of-hospital births.

Hire a professional labor support person. She will know nonmedical techniques to help keep or get your labor back on track. She will also provide continuous support, encouragement, and reassurance to you and your partner.

Have confidence in yourself and your body. Doctors tend to instill doubt. The fact that cesarean section is so common these days does the same: if you don’t think you can birth your child, it may become a self-fulfilling prophecy.

Have realistic expectations of labor length and difficulty. Impatience and frustration are your worst enemy. They can lead you to make choices you may regret.

Address emotional issues that may be problematic in labor. For example, women who experienced sexual abuse in childhood or have prior traumatic birth experiences or have strong control issues may sometimes have difficulty surrendering to the labor. If this is true for you, consciousness of this can help you and those with you work out strategies to prevent or cope with their potential effects on labor. Please, though, do not blame yourself if labor is slow and you cant fix it.

Avoid induction of labor. See chapter 3.

Unless there are medical reasons to go to the hospital early in labor, stay home until labor becomes active. If you aren’t sure, during the day you can go into your caregivers office to be checked, and at night, they can check you at the hospital. don’t stay, though, if not much is happening. Studies show that women who are admitted in prelabor or very early labor are more likely to have oxytocin, instrumental vaginal delivery, and c-sections.

Refuse a cesarean for poor progress prior to active phase labor. This means at least 3-4 cm dilation if you have had children before and 4-5 cm dilation if you haven’t. Both the U.S. and Canadian obstetricians professional organizations state that cesareans for this reason should not be done in early labor.

Avoid frequent vaginal exams, but when you have them, get information on more than just dilation. Avoid frequent exams because finding there is little or no change in dilation can be intensely disappointing. Find out about the state of the cervix, how far down the baby is, and, if possible, the baby’s position. You may be making important progress even though you are not dilating, and often, advances in these areas may be necessary before dilation continues.

In labor, stay active, change positions frequently, maintain liquid and calorie intake, use warm tub baths or showers, and avoid flat-on-the-back or nearly flat-on-the-back pushing positions. These strategies promote good progress. You can bathe or shower with an IV as it can be covered with plastic and taped. You can bathe with ruptured membranes.

Take steps to rotate a posterior baby. don’t wait until you are dilated enough for someone to tell the baby’s position by feeling her head vaginally. Assume a posterior baby if contractions are strong but produce little progress. None of these recommendations will hurt if the baby isn’t posterior. Activities such as climbing stairs, crawling, pelvic rocks, and hip swivels help jiggle the baby around. Assuming an all-fours position, or an open lunge during the cervical dilation phase and all-fours or squatting during pushing uses gravity to swing the baby’s back into your belly or the leverage of your legs to expand the pelvis. Likewise, the double-hip squeeze opens the pelvis. Assuming a knee-chest position in early labor (this may be too uncomfortable in active labor) disengages the head from the pelvis, and the dangle during pushing elongates the torso, both of which give the baby more room to come around. Some midwives may offer to turn the baby manually early on during a vaginal exam. This will be painful but can transform the labor according to midwives who do it. However, there are no formal data on the efficacy or safety of this procedure.

Avoid epidural anesthesia. Epidurals slow labor, cause persistent posterior babies, and increase the risk of cesarean for poor progress.

Nipple stimulation can intensify weak contractions and can avoid the need for IV oxytocin. Stimulating the nipples causes the release of additional oxytocin. Stimulation can be manually, by electric breast pump, or via a TENS (transcutaneous electronic nerve stimulation) unit, a physical therapy device that painlessly delivers a low electric current through pads applied to the skin.

If you require oxytocin, make sure it is given a fair trial. A study of a protocol mandating at least 4 hours of adequate contractions on oxytocin in women with arrested labor progress and longer if contractions could not be brought up to par achieved an 8% cesarean rate. This was despite nearly all women having epidurals (epidurals slow labor). If, as is not uncommon, cesareans had been done after 2 hours on oxytocin with inadequate progress, the cesarean rate would have been 23%.

Refuse an instrumental delivery or cesarean section recommended solely on an arbitrary time limit. Both the Canadian and U.S. obstetricians professional organizations state there is no need to deliver the baby provided some progress is being made and the baby is doing well.

cesarean section: See p.21.

  • The hormones of pregnancy soften the joints of the normally rigid pelvis. [Back to text]

Gleanings From the Medical Literature

Nonmedical factors often determine the diagnosis and treatment of slow labor.

High-dose oxytocin regimens pose risks.

Active management is at worst, ineffective, and at best, unnecessary.

Active management does not eliminate the adverse effects of epidurals.

Simple, noninvasive strategies may safely and effectively enhance labor progress during the dilation and pushing phases of labor as well as make for a pleasanter labor.

Women admitted to the hospital in early or prelabor may be more likely to have labor interventions.

Bibliography

ACOG. Dystocia and the augmentation of labor. Technical Bulletin No. 218, 1995.

Albers LL, Schiff M, and Gorwoda JG. The length of active labor in normal pregnancies. Obstet Gynecol 1996;87(3):355-9.

Boyd ME, Usher RH, and McLean FH. Fetal macrosomia: prediction, risks, proposed management. Obstet Gynecol 1983;61(6):715-22.

Boylan PC. Active management of labor: results in Dublin, Houston, London, New Brunswick, Singapore, and Valparaiso. Birth 1989;16(3):114-118.

Cahill DJ, Boylan PC, and OHerlihy C. Does oxytocin increase perinatal risk in primigravid labor? Am J Obstet Gynecol 1992;166(3):847-50.

Consensus Conference Report. Indications for cesarean section: final statement of the panel of the National Consensus Conference on Aspects of Cesarean Birth. Can Med Assoc J 1986;134:1348-52.

Cavlovich FE. Subgaleal hemorrhage in the neonate. J Obstet Gynecol Neonatal Nurs 1995;24(5):397-404.

Drife JO. Choice and instrumental delivery. Br J Obstet Gynaecol 1996;103(7):608-11.

FDA. FDA public health advisory: need for CAUTION when using vacuum assisted delivery devices. May 21, 1998. http://www.fda.gov/cdrh/fetal/598.html.

Granstrom L, Ekman G, and Malmstrom A. Insufficient remodelling of the uterine connective tissue in women with protracted labour. Br J Obstet Gynaecol 1991;98:1212-6.

Hankins GDV and Rowe TF. Operative vaginal delivery–year 2000. Am J Obstet Gynecol 1996;175(2):275-82.

Hemminki E et al. Ambulation versus oxytocin in protracted labour: a pilot study. Eur J Obstet Gynecol Reprod Biol 1985;20:199-208.

Keller JD et al. Shoulder dystocia and birth trauma in gestational diabetes: a five-year experience. Am J Obstet Gynecol 1991;165(4 Pt 1):928-30.

Klaus MH. Intermittent versus continuous support of women in labor. Presented at Innovations in Perinatal Care: Assessing Benefits and Risks, twelfth conference sponsored by the journal Birth and the Boston University School of Public Health, Waltham, MA, June 5-7, 1998.

Kitzinger S. The desexing of birth; some effects of professionalization of care; the god-sibs; what matters to women–their words. Paper presented at Innovations in Perinatal Care: Assessing Benefits and Risks, ninth conference presented by Birth, San Francisco, November 1990.

Lucas MJ. The role of vacuum extraction in modern obstetrics. Clin Obstet Gynecol 1994;37(4):794-805.

Lumley J. Events and experiences in childbirth: is there an association with postpartum depression? Presented at the 10th Birth conference, Boston, Oct 31-Nov1, 1992.

Macara LM and Murphy KW. The contribution of dystocia to the cesarean section rate. Am J Obstet Gynecol 1994;171(1):71-7.

McDonald D et al. The Dublin randomized controlled trial of intrapartum fetal heart rate monitoring. Am J Obstet Gynecol 1985;152(5):524-539.

Menticoglou SM, Perlman M, and Manning FA. High cervical spinal cord injury in noenatres delivered with forceps: a report of 15 cases. Obstet Gynecol 1995;86(4 Pt 1):589-94.

Meyer L et al. Maternal and neonatal morbidity in instrumental deliveries with the Kobayashi vacuum extractor and low forceps. Acta Obstet Gynecol Scand 1987;66:643-7.

O’Driscoll K and Meagher D. Active management of labour. 2d ed. London: Bailliere Tindall, 1986.

Olah K. The active mismanagement of labour. Br J Obstet Gynaecol 1996;103:729-31.

Rouse DJ, Owen J, and Hauth JC. Active-phase labor arrest: oxytocin augmentation for at least 4 hours. Obstet Gynecol 1999;93(3):323-8.

Shyken JM and Petrie RH. The use of oxytocin. Clin Perinatol 1995;22(4):907-31.

Siegel P. Does bath water enter the vagina? Obstet Gynecol 1960;15:660-1.

Simkin P. Stress, pain and catecholamines in labor: part 2. Stress associated with childbirth events: a pilot survey of new mothers. Birth 1986;13(4):234-240.

Thornton JG and Lilford RJ. Active management of labour: current knowledge and research. BMJ 1994;309(6951):366-9.

Ventura SJ et al. Report of final natality statistics, 1995. Month Vital Stat Rep 1997;45(11, Suppl):1-80.

Wainer-Cohen N. Personal communication, Jun 7, 1998.

Williams MC. Vacuum-assisted delivery. Clin Perinatol 1995;22(4):933-52.

© 1999 by Perigee Books

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