for Normal Birth

No Need to Continue Oxytocin Infusion after Active Labor Established in Induction of Labor

Daniel-Spiegel, E., Weiner Z., et al. (2004). "For how long should oxytocin be continued during induction of labour?" BJOG: an International Journal of Obstetrics & Gynaecology. 111 (4): 331-4. [Abstract]

Summary: In this prospective trial conducted in Afula, Israel, patients presenting for induction of labor were randomized to an experimental protocol where oxytocin infusion was discontinued once cervical dilatation reached five centimeters (n=48) or to a traditional protocol where oxytocin infusion continued until delivery (n=48). Women with singleton pregnancies, fetal vertex presentation and an estimated fetal weight of less than 4250 grams (9lb 6oz) were eligible for the study if there was no history of more than one previous cesarean section or persistent non-reassuring fetal heart rate in the current pregnancy. Indications for induction included post dates pregnancy (beyond 42 weeks), rupture of membranes for more than 24 hours, oligohydramnios (low amniotic fluid volume), intrauterine growth restriction, diabetes, and sporadic non-reassuring fetal heart rate pattern. There were no statistically significant differences in background characteristics, reason for induction, or cervical condition before induction between the experimental and control groups.

The active phase of labor was shorter in the group where oxytocin infusion was discontinued at five centimeters compared with the control group, although this difference was not statistically significant (p=0.07). There were no statistically significant differences in length of second stage of labor, maximal dose of oxytocin infused, frequency of contractions prior to onset of active labor, non-reassuring fetal heart rate patterns, uterine hyperstimulation, use of analgesia during labor, or mode of delivery. The researchers concluded that there is no benefit to continuing oxytocin infusion after the onset of active labor and suggest that a larger study might have power to detect potential disadvantages or risks of continuing oxytocin infusion beyond this point. Previous research that examines the effect of continuous oxytocin infusion on the number and behavior of oxytocin receptors suggests that there may be a point at which administering more oxytocin begins to desensitize uterine receptors, which in turn may have an opposite effect on the progress of labor when labor induction is undertaken. For this reason, the authors speculate that continuing oxytocin infusion beyond the onset of active labor may interfere with labor progress.

Significance for Normal Birth : Normal labor begins on its own. However, when induction of labor is indicated for medical reasons, the goal should still be to minimize the use of interventions and maintain the normalcy of other aspects of the labor and birth. This study provides a strong justification for discontinuing oxytocin infusion once an active labor pattern is established. This in turn eliminates the need for continuous fetal monitoring which is routinely applied during pharmacologic induction. Once continuous fetal monitoring is discontinued, the woman is able to move freely and change position in labor.

Emerging research on the physiologic effects of oxytocin during labor provides the rationale for the conduct of this study. As more research is undertaken that further illuminates the complex hormonal interactions that occur during normal birth, we can begin to discover new ways minimize the impact of interventions such as labor induction or augmentation when these interventions are medically necessary. [Abstract]

No Role for Episiotomy When Perineal Tear is Presumed to be Imminent

Dannecker, C., Hillemanns, P., et al. (2004). "Episiotomy and perineal tears presumed to be imminent: randomized controlled trial." Acta Obstetricia et Gynecologica Scandinavica. 83 (4): 364-8. [Abstract]

Summary: This prospective randomized trial compared maternal and perinatal outcomes of a restricted policy where episiotomy was only performed for fetal indications (n=49) and a liberal policy where episiotomy was performed for fetal indications or when a perineal tear was judged by the birth attendant to be imminent (n=60). Primiparous women with uncomplicated singleton pregnancies at >34 weeks gestation were enrolled in the study. Episiotomies were mediolateral (cut diagonally toward the buttocks) and were performed by obstetricians or midwives . Tears were judged to be imminent when the perineal tissue was pale and extremely thin during crowning of the fetal head.

Restrictive use of episiotomy only for fetal indications resulted in a 36 percent lower episiotomy rate and a three-fold increase in the rates of intact perinea and minor perineal trauma. There were no statistically significant differences in rates of third-degree tears, anterior lacerations, maternal blood loss, Apgar scores, or umbilical artery pH values. This study did not measure long-term outcomes such as pelvic floor strength, urinary incontinence or sexual functioning.  The study took place in an institution in Germany that formerly had a policy of routine episiotomy. This may account for the high episiotomy rate in both study groups (41 percent in the restrictive group and 77 percent in the liberal group).

The authors conclude that performing mediolateral episiotomies when tears are presumed to be imminent provides no benefit to the mother or newborn and causes increased perineal trauma and postpartum pain.

Significance for Normal Birth: Birth is normal when there are no routine interventions. In the United States , the rate of episiotomy has decreased significantly since the evidence began to show that restricted use of this intervention resulted in better maternal outcomes than routine use, with no adverse effects for the newborn. However, “restricted use” is poorly defined, and many practitioners continue to cut episiotomies for maternal indications, primarily to avoid a tear that is presumed to be imminent. This study shows that episiotomy rates may be further reduced, with better maternal outcomes and no adverse effects for the newborn, when the intervention is only performed for fetal indications such as acute fetal distress. While this study took place in Germany where mediolateral episiotomy is performed, it is probable that similar results would be found in the United States , where midline episiotomy (toward the anus) is the norm. [Abstract]

Parents as Good as Nurses at Maintaining Thermal Stability During the Newborn's First Bath

Medves, J. M. and O'Brien, B. (2004). "The effect of bather and location of first bath on maintaining thermal stability in newborns." JOGNN - Journal of Obstetric, Gynecologic, & Neonatal Nursing. 33 (2): 175-82. [Abstract]

Summary: This randomized controlled trial compared the effect of bather (parent or nurse) and location (bedside or nursery) on the thermal stability of newborns during the first bath. Newborns born vaginally at term (at least 37 weeks) with a five minute Apgar score of at least 7 were included in the sample. The babies were immersed in a tub bath (as opposed to receiving a sponge bath) in both groups. Fifty-five newborns were randomized to receive their first bath by a parent at the bedside. Parents received detailed instructions on how to bathe the baby and avoid excessive heat loss. Newborns were dried, wrapped in a warm towel, and held by their mother or father after the bath. Fifty-six newborns were randomized to the standard bathing protocol. In this protocol, the newborns were placed on a radiant warmer before the bath, bathed by a nursery nurse, and rewarmed on the radiant warmer until the axillary temperature was at least 36.5ºC (97.7ºF), at which time they were dressed and returned to the bedside. In both groups, babies were immersed in bath water that was 38ºC (100.4ºF). Newborn temperatures were measured five times: before the bath, after the face and hair wash, after 30 seconds of tub immersion, immediately following drying, and one hour after the bath. There were no differences in birth weight or demographic characteristics between the two groups.

There were no statistically significant differences in mean newborn temperature measurements or the number of newborns whose temperature dropped below 36ºC (96.8ºF) between the two groups. Use of the radiant warmer prior to the bath was associated with a significantly higher likelihood of hyperthermia. This difference likely accounts for the greater overall heat loss experienced by those newborns who were bathed by nurses in the nursery under the standard protocol.

Parents who were randomized to give the first bath reported that they enjoyed and gained confidence from bathing their newborns. The potential opportunity to give the first bath was the most common reason that parents gave for enrolling in the study. This indicates that parents value the opportunity to care for their infants during the early newborn period.

Significance for Normal Birth: In normal birth, there should be no separation of mother and baby. However, hospitals commonly have routines that call for the first bath to take place soon after birth, usually within the first 2-4 hours. In many settings, the first bath is given by a nurse in a central nursery with no parent or only the father/co-parent present. Concerns about newborn thermal stability provide the rationale for nurses giving the first bath, since they presumably are skilled in minimizing newborn heat loss. This study provides strong evidence that, with proper instructions and attention given to the bathing environment (minimizing drafts, ensuring correct water temperature, etc.), parents are as good as nurses at maintaining thermal stability in the newborn. Allowing parents to give the first bath at the bedside minimizes early separation of mother and infant. It also may provide important opportunities for bonding and for educating parents in newborn care. [Abstract]

Beneficial Effects of Kangaroo Care Are Not Limited to Preterm Newborns

Ferber, S. G. and Makhoul, I.R. (2004). "The effect of skin-to-skin contact (kangaroo care) shortly after birth on the neurobehavioral responses of the term newborn: a randomized, controlled trial." Pediatrics. 113 (4): 858-65. [Abstract]

Summary: This randomized controlled trial compared the self-regulation and neurobehavioral patterns of term newborns who received “kangaroo-care” (prolonged skin-to-skin contact) soon after birth with those of term newborns who were separated from their mothers after birth. Immediate postnatal care was identical in both groups and involved being dried placed on the mother's chest for 5-10 minutes then being removed from the delivery room to be weighed and dressed. Newborns in the experimental group (n=25) were returned to the delivery room where they were undressed and placed between their mothers' breasts with a blanket over their backs for an additional hour. Control group infants (n=22) remained in the nursery during the first hour of the mother's postpartum recovery. A 60-minute behavioral observation was conducted four hours after delivery. During the observation, researchers measured neurobehavioral adaptation using standard definitions and instruments previously described in the relevant literature.

Infants who received kangaroo care spent significantly more time in sleep states, especially in quiet sleep, and less time in transitional, fussy, crying, or alert states, than infants who were separated from their mothers. Infants in the experimental group also exhibited more motor control, evidenced by more flexed and fewer extended movements. Other elements of neurobehavioral adaptation were studied, but no statistically significant differences were found in these characteristics. The results indicate that kangaroo care may be beneficial in helping term infants self-regulate with respect to motor systems balance and sleep organization during the transition out of the womb. The authors conclude that healthy term infants who receive kangaroo care shortly after birth may be better equipped to make “biologically cost-effective use of internal resources.”

Significance for Normal Birth: This study shows that hospital routines that separate mother and baby have an adverse effect on normal newborn adaptation to extrauterine life. Even after a normal labor and birth, the newborn has many complex tasks to undertake in order to make a smooth transition out of the womb and remain healthy. Extended skin-to-skin contact is the healthy norm among mammals. This study provides evidence that this “intervention” helps babies minimize time and energy spent regulating sleep states and motor activity, potentially freeing internal resources for use in regulating other essential systems such as the cardiovascular and respiratory systems.

While there is copious research that supports the use of kangaroo care for preterm infants, this is one of the few studies that address the effects of kangaroo care for the healthy term infant. The study was conducted in an institution in northern Israel where the standard postpartum routine calls for extended separation of mother and baby with no opportunity to feed the baby (at the breast or with formula) before six hours of life. It is likely that neurobehavioral adaptations could be further enhanced if the mother-infant pairs were provided unlimited opportunity to breastfeed in addition to extended skin-to-skin contact. [Abstract]

Previous Cesarean Section Increases Risk of Unexplained Stillbirth in Subsequent Pregnancies

(Submitted by Sara Foster, Ypsilanti , MI )

Smith, G. C., Pell, J.P., et al. (2003). "Caesarean section and risk of unexplained stillbirth in subsequent pregnancy." Lancet. 362 (9398): 1779-84. [Abstract]

Summary: Researchers examined the relative risk of stillbirth in the second pregnancy among women who had undergone cesarean delivery in the first pregnancy in this retrospective study. Data were collected from the Scottish Morbidity Record, which collects information on all patients discharged from maternity hospitals, and the Scottish Stillbirth and Infant Death Enquiry, a national register of perinatal deaths, for the period 1992-1998. These mandatory registers have been found in previous studies to be reliable, valid, and over 99 percent complete.

All second births that occurred in the study period in Scotland were identified and records were matched with those from the first pregnancies in the same woman. Women were excluded from the study group if their second pregnancy resulted in an infant death due to a congenital anomaly. The final sample included 17,754 second births among women who previously gave birth by cesarean section and 102,879 second births among women who previously gave birth vaginally. The risk of stillbirth was compared between those mothers with a previous caesarean section and those without, and secondary analyses were conducted to determine the cause of stillbirth and the gestational age at which the perinatal death occurred.

Women who previously delivered by cesarean section had a significantly increased risk of an unexplained stillbirth in the next pregnancy when compared to women who had previously delivered vaginally. The excess risk was apparent from 34 weeks of gestation onward and was still observed when the authors controlled for differences in maternal characteristics, indications for the previous cesarean section and outcomes of the first pregnancy. The risk of stillbirth from 39 weeks gestation was 1.06 per 1000 in women with a previous cesarean section. This is more than double the risk in women without a previous cesarean delivery (0.47 per 1000). Women with a history of cesarean section in the first pregnancy also had significantly higher rates of fetal intrauterine growth restriction and preterm delivery compared with those who had previously delivered vaginally.

The authors suggest that the increased risk of stillbirth in women with a history of cesarean section might be explained by the association between previous cesarean section and complications with the placenta (placental abruption, placenta previa and placenta accreta). The difference may also be explained by surgical factors such as disruption of the major uterine blood vessels during the cesarean section procedure, leading to impaired blood flow to the placenta and fetus in later pregnancies.

Significance for Normal Birth: Many practices that support and promote normal birth are associated with decreased risk of cesarean section. Conversely, practices that interrupt the normal progress of labor and birth often increase the risk of cesarean section. A growing body of research now points to the risks of cesarean delivery on subsequent pregnancies, including increased risk of complications of the placenta. The Scottish national registers used in this study provide a unique opportunity to look at the impact of cesarean delivery on subsequent pregnancies in a large number of women. The association between previous cesarean section and unexplained stillbirth provides evidence of a previously unappreciated risk of cesarean birth. Women who are considering elective cesarean section or who are faced with interventions in labor that increase their risk for cesarean delivery must be aware of the full range of risks of cesarean birth, including long term risks related to future pregnancies. [Abstract]