Submitted by
Dr. Susan Virginia Mead
Department of Social Work and Sociology
Ferrum College

August 5, 1999

For his doctoral dissertation written at Stanford University, Peter F. Schlenzka recently finished an extensive study of perinatal outcomes in out-of-hospital and in-hospital births. Outlining his reason for undertaking the study, Schlenzka states that research has suggested that the "medicalization of childbirth and the move of childbirth from home to the hospital might not have improved the outcomes for these low risk pregnancies" which constitute 60-80% of all pregnancies (p. 1). In his own research, Schlenzka sets out to study perinatal mortality of pregnant women with equal risk levels to determine whether or not "the non-interventionist [physiological] ... approach to childbirth, as administered by midwives and some physicians in free-standing birth centers or at home, is as safe as the interventionist obstetric approach in hospitals." His methodology allows for insights into the outcomes of both low-risk and high-risk pregnancies and births—in and out of the hospital. In addition, Schlenzka examines evidence of the "overall social and economic cost to society" of these two approaches to maternal care (p. 3).

As is standard in all doctoral research, Schlenzka has conducted a thorough review of scientific literature which pertains to the study he undertakes in this dissertation. His bibliography consists of 189 references and he includes over 50 pages of literature review on such topics of the medicalization of childbirth, the shift from home-birth to hospital birth, the safety of obstetric and natural approaches, and the re-emergence of midwifery. Some critical statements he cites from others’ research are cited on pages three and four of this summary.

In his study, Schlenzka examines information from live birth and fetal death records for children in the 1989 and 1990 birth cohort, hospital discharge data reporting medical risk factors, and various information about free-standing birth centers. After careful matching of all appropriate data, Schlenzka examines perinatal outcomes of nearly 816,000 births, comparing low risk births outside and inside the hospital and high-risk births outside and inside the hospital. His findings clearly show that the natural [physiological] approach and obstetric approach produce the same perinatal mortality outcomes for both low-risk and high-risk births. Thus, he concludes: "the obstetric approach cannot claim to have lower perinatal mortality rates than the natural approach to childbirth," with the natural approach in this case being defined as births planned in out-of-hospital settings—that is, at home or in a free-birth center (p. 175, 174).

To examine the social and economic costs of birth, Schlenzka’s study compares "the present hospital-based obstetric care system with a shared maternity care system where midwives are the primary caregivers attending low-risk women (the majority of all pregnancies) and using the natural approach while obstetricians use their interventionist approach only for the remaining cases with complications" (p. 175). His first observation is that "a shared maternity care system would lower the cost for childbirth by roughly 40%, or $13.143 billions" (p. 175).

Schlenzka also suggests that under the shared maternity care model, there would be a lessening of costs from the reduction of unnecessary cesareans and other obstetric interventions. Finally, he reviews research that suggests that a wide variety of social ills that have been linked to birth trauma, such as lack of bonding between the mother and infant, involve a great economic and social cost to society--and that a less interventive birth model would reduce these ills. From this analysis, Schlenzka concludes that the "apparent disadvantages of the obstetric approach have such large order of magnitude, that in any clinical trial it would be considered unethical to continue with the obstetric ‘treatment’" (p. 175).

Schlenzka’s data from more than 800,000 births show no advantage of the obstetric approach for either low or high risk women. Furthermore, Schlenzka is able to show a slightly (though not significantly) better outcome in terms of lower perinatal mortality for low-risk women who opt for out-of hospital settings. After analyzing all of his data on perinatal outcomes, Schlenzka states the following (p. 153):

Under no circumstances do the California data for 1989 and 1990 allow the obstetric profession to uphold the claim that for the large majority of low-risk women hospital birth is "safer" with respect to perinatal mortality. Our data also suggest that even for the high-risk levels of our Study Population the natural approach (including transfers) produces the same perinatal mortality outcomes as the obstetric approach.

In his abstract, Schlenzka concludes (p. iv-v):

Given no differences in perinatal mortality it must be noted that the natural approach shows significant advantages with respect to lower maternity care cost as well as reduced mortality and morbidity from unnecessary cesareans and other obstetric interventions, and significant benefits from avoiding negative long-term consequences from unnecessary obstetric interventions and procedures. These advantages of the natural [physiological] approach are of such a large order of magnitude as to raise serious doubts concerning the appropriateness of conventional "obstetric" treatment for low-risk childbirth.

Critical Quotes from the Review of Literature in
Peter F. Schlenzka, "Safety of Alternative Approaches to Childbirth,"
Stanford University, March 1999.

(Full citations appear in the Reference section)

"The woman’s choice itself may influence her level of anxiety and apprehension, and in obstetrics levels of anxiety have been shown to predict obstetric complications" (p. 3--from Wiegers et al 1996).

The "medicalized approach to childbirth (the obstetric approach) is based on medicine’s belief that every birth has a high potential for pathology…It is no wonder then that the obstetric approach focuses on the pathologies in the labor and delivery phase, and the physician tends to take charge in the patient-doctor interaction and sees himself as the decisionmaker" (p. 4—with contributions from Davis-Floyd 1994 and Rooks 1997).

"Midwifery is rooted in the natural approach. Pregnancy and birth are considered fundamentally healthy processes which have many normal variations; it is normal part of life, not a medical condition…Only when complications occur which are beyond the midwife’s expertise, is the woman transferred to obstetric care" (p. 6—from Steiger 1987).

"Treating normal labors as though they were complicated can become a self-fulfilling prophecy" (p. 6—from Rooks 1997).

"[Birth] can be a most empowering act of creation in a woman’s life…Midwives…perceive part of their role to "empower" the pregnant women…. Dr. Michel Odent argues that "experiences have clearly shown that an approach which "demedicalizes" birth, restores dignity and humanity to the process of childbirth, and returns control to the mother is also the safest approach"’ (p. 7---with contributions from Odent 1984 and Rooks 1997).

"several observational studies carried out during the last two decades suggest that out-of-hospital birth is as safe as hospital birth for women with comparable low-risk profiles (Kloosterman 1984; Mehl et al. 1976; Tew 1977b; Van Alten, Eskes and Treffers 1989)
…Marjorie Tew showed that …birth in obstetric hospitals was significantly less safe than in general practitioner units or home birth…[and] that birth at home and in General Practitioner Units (GPU) was not only safer for low-risk pregnancies, but also for the high-risk cases (Tew 1990, pp. 241-245)." (p. 12, 13, 16---from studies cited in quote).

"’reluctance of the obstetric establishment to consider the implications of objective evidence which runs counter to their preconceived assumptions -- without refuting it on statistical grounds" (Zander 1984, p. 128)’" (p. 17--- quote from Zander).

"For the Netherlands, as the only country with a sizable proportion of natural childbirths (home birth as proxy)…Dutch national perinatal statistics from 1986 …found that perinatal mortality rates were much higher for obstetricians in hospitals than for midwife-attended home care or midwife-attended hospital care, at all levels of risk when controlling for gestation, maternal age and parity" (p. 17---from studies by Treffers and Laan 1986 and Tew and Damstra-Wijmenga 1991).

"The WHO [World Health Organization] commissioned in 1979 a Perinatal Study Group to examine the "problems surrounding birth and birth care" and …the recommendations …strongly argue for a non-interventionist approach to childbirth" (p. 17---from WHO 1985 #6).

"A recent meta-analysis of planned home birth vs. planned hospital birth of studies published after 1970 found six studies (from Australia, Netherlands, Switzerland, UK, two from the US) which met the selection criteria and concludes that perinatal mortality was not significantly different in the home and hospital groups in any individual study" (p. 18---from Olsen 1997).

"Dr. C. Arden Miller, chairman of the Department of Maternal and Child Health at the University of North Carolina School of Public Health and a past-president of the American Public health Association, testified in a 1980 hearing on the obstacles to nurse-midwifery practice. He stated, "If one looks for reasons why this country is deprived in many areas of the services of midwives, one has to look in the political and economic arenas. The answer is not to be found in terms of health outcomes" (pp. 19-20---from Rooks 1997).

"in a double blind clinical trial at the Los Angeles County and USC Women’s Hospital, 492 low risk women who qualified for the hospital’s Normal Birth Center were randomly assigned to either the midwifery service in the birth center or to the physician service in the maternity ward (Chambliss et al. 1992). While there were no differences in the demographics of the two groups or in neonatal outcome, the physicians had significantly higher intervention rates than the midwives" (pp. 21-22—this statement is followed by several other studies that showed no differences in fetal or neonatal outcomes but marked differences in intervention and subsequent differences in maternal satisfaction, favoring non-interventive settings).

"the lower rate of interventions in home births meant a lower risk of subsequent complications for the mother…’Usually it takes a certain tenacity for women to realize a home birth in a health care system in which this is considered irresponsible’" (p. 27---from Ackermann-Liebrich et al. 1996, p. 1317).


Primary Reference: Schlenzka, Peter F. 1999. "Safety of Alternative Approaches to Childbirth." Unpublished Dissertation. Palo Alto, Calif: Stanford University.

Secondary References as cited in Schlenzka, 1999: (the summary cites only 28 of his 189 references)

Ackermann-Liebrich, Ursula, Thomas Voegeli, Kathrin Gunter-Witt, Isabelle Kunz, Maja Zullig, Christian Schindler, and Margrit Maurer. 1996. "Home versus Hospital Deliveries: Follow-up Study of Matched Pairs for Procedures and Outcome." British Medical Journal 313:1313-1318.

Chambliss, Linda R., Cornelia Daly, Arnold L. Medearis, Mary Ames, Martha Kayne, and Richard Paul. 1992. "The Role of Selection Bias in Comparing Cesarean Birth Rates Between Physician and Midwifery Management." Obstetrics and Gynecology 80:161-165.

Davis-Floyd, Robbie E. 1994. "The Technocratic Body: American Childbirth as Cultural Expression." Social Science and Medicine 38:1125-1140.

Kloosterman, G. J. 1984. "The Dutch Experience of Domiciliary Confinements." Pp. 115-125 in Pregnancy Care for the 1980's, edited by Geoffrey Chamberlain and Luke Zander. London: The Royal Society of Medicine & The Macmillan Press Ltd.

Mehl, L. F., L. A. Leavitt, G. H. Peterson, and D. C. Creevy. 1976. "Home versus Hospital Delivery: Comparison of Matched Populations." in Annual Meeting of the American Public Health Association. Miami Beach, FL.

Odent, Michel. 1984a. Birth Reborn. New York: Pantheon.

Olsen, Ole. 1997. "Meta-Analysis of the Safety of Home Birth." BIRTH 24:4-13.

Rooks, Judith Pence. 1997. Midwifery and Childbirth in America. Philadelphia: Temple University Press.

Steiger, Carolyn. 1987. Becoming a Midwife. Portland. OR: Hoogan House.

Tew, Marjorie. 1977a. "Obstetric Hospitals and General-PractionerUnites: The Statistical Record." Journal of the Royal College of General Practioners 27:689-694.

Tew, Marjorie. 1977b. "Where to Be Born." New Society 27:120-121.

Tew, Marjorie. 1978. "The Case against Hospital Deliveries: The Statistical Evidence." Pp. 55-65 in The Place of Birth, edited by Sheile Kitzinger and John A. Davis. Oxford: Oxford University Press.

Tew, Marjorie. 1984. "Understanding Intranatal Care through Mortality Statistics." Pp. 105-114 in Pregnancy Care for the 1980's, edited by Luke Zander and Geoffrey Chamberlain. London: The Royal Society of Medicine & The Macmillan Press Ltd.

Tew, Marjorie. 1985a. "Place of Birth and Perinatal Mortality." Journal of the Royal College of General Practitioners 35:390-394.

Tew, Marjorie. 1985b. "Safety in Intranatal Care: The Statistics." Pp. 203-223 in Modern Obstetrics in General Practice, edited by G. N. Marsh. New York: Oxford University Press.

Tew, Marjorie. 1985c. "We Have the Technology." Nursing Times 81:22-24.

Tew, Marjorie. 1986a. "Do Obstetric Intranatal Interventions Make Birth Safer?" British Journal of Obstetrics and Gynaecology 93:659-674.

Tew, Marjorie. 1986b. "Home, Hospital, or Birthroom." The Lancet ii:749-749.

Tew, Marjorie. 1986c. "The Practices of Birth Attendants and the Safety of Birth." Midwifery 2:3-10.

Tew, Marjorie. 1988. "General Practitioner Obstetrics: Does Risk Prediction Work." Journal of the Royal College of General Practitioners 38:521-521.

Tew, Marjorie. 1990. Safer Childbirth? A Critical History of Maternity Care. London: Chapman and Hall.

Tew, Marjorie, and S. M. I. Damstra-Wijmenga. 1991. "Safest Birth Attendants: Recent Dutch Evidence." Midwifery 7:55-63.

Treffers, Pieter E., and R. Laan. 1986. "Regional Perinatal Mortality and Regional Hospitalization at Delivery in The Nederlands." British Journal of Obstetrics and Gynaecology 93:690-693.

Van Alten, Dik, Martine Eskes, and Pieter E. Treffers. 1989. "Midwifery in the Netherlnds. The Wormerveer Study: Selection, Mode of Delivery, Perinatal Mortality and Infant Morbidity." British Journal of Obstetrics and Gynaecology 96:656-662.

Wiegers, T. A., M J N C Keirse, J. van der Zee, and G. A H. Berghs. 1996. "Outcome of Planned Home and Planned Hospital Births in Low Risk Pregnancies: Prospective Study in Midwifery Practices in the Netherlands." British Medical Journal 313:1309-1313.

World Health Organization. 1985a. "Appropriate Technology for Birth." The Lancet II/85:436-437.

World Health Organization. 1985b. Having a Baby in Europe. Copenhagen: WHO Regional Office for Europe.

Zander, Luke. 1984. "The Significance of the Home Delivery Issue." Pp. 126- 132 in Pregnancy Care for the 1980's, edited by Geoffrey Chamberlain and Luke Zander. London: The Royal Society of Medicine & The Macmillan Press.

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