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Am J Perinatol 2012; 29(01): 07-18
DOI: 10.1055/s-0031-1285829
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Cesarean versus Vaginal Delivery: Whose Risks? Whose Benefits?

Kimberly D. Gregory
1   Department of Obstetrics and Gynecology, Cedars Sinai Medical Center/Burns Allen Research Institute, Los Angeles, California
2   David Geffen School of Medicine and UCLA School of Public Health, Los Angeles, California
,
Sherri Jackson
1   Department of Obstetrics and Gynecology, Cedars Sinai Medical Center/Burns Allen Research Institute, Los Angeles, California
,
Lisa Korst
3   Department of Obstetrics and Gynecology, University Southern California, Keck School of Medicine, Los Angeles, California
,
Moshe Fridman
4   AMF Consulting, Los Angeles, California
› Author Affiliations
Further Information

Publication History

01 June 2011

06 June 2011

Publication Date:
10 August 2011 (online)

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Abstract

We reviewed the risks and benefits of vaginal and cesarean delivery to help frame the inherent trade-offs that should be considered as part of the informed consent discussion between patients and providers. We performed a targeted literature review for common complications of childbirth. Approximately 30% of women will experience a maternal or neonatal complication during childbirth. Both cesarean and vaginal delivery is associated with well-known measurable short- and long-term maternal and neonatal complications and benefits. Childbirth is not risk free. There are data available that can guide the informed consent process with objective quantifiable data that patients and providers can use to weigh risks and benefits of delivery methods.

Keywords

cesarean delivery - labor and delivery complications - informed consent - obstetric quality and safety
 

  • References

  • 1 Thorp JM. Clinical aspects of normal and abnormal labor. In: Creasy RK, Resnik R, Iams JD, Lockwood CJ, Moore TR, , et al, eds. Creasy & Resnik's Maternal-Fetal Medicine Principles & Practices. 6th ed. Philadelphia, PA: : Saunders Elsevier; ; 2009: 692-724
    Google Scholar
  • 2 Guise JM, Eden K, Emeis C, Denman MA, Marshall N, Fu R, Janik R . et al. Vaginal Birth after Cesarean New Insights. Evidence Report/Technology Assessment No. 191. AHRQ Publication No 10–E003. Rockville MD: : Agency for Healthcare Research and Quality; ; March 2010
    Google Scholar
  • 3 Menacker F, Hamilton BE. Recent trends in cesarean delivery in the United States. NCHS Data brief, No. 35. Hyattsville, MD: : National Center for Health Statistics; ; 2010. Available at: http://www.cdc.gov/nchs/data/databriefs/db35.htm . Accessed May 1, 2011
    Google Scholar
  • 4 National Vital Statistics Reports, Volume 57, Number 12, March 18, 2009. http://www.cd..gov/nchs/data/nvsr/nv28.2sr57/nvsr57_12.pdf
    PubMedGoogle Scholar
  • 5 National Vital Statistics Reports, Vol. 58, No. 19, May 20, 2010. http://w33.4ww.cdc.gov/nchs/data/nvsr/nvsr58_19.pdf
    PubMedGoogle Scholar
  • 6 National Women's Law Center. Maternal Mortality Rate (per 100,000). Available at: http://hrc.nwlc.org/status-indicators/maternal-mortality-rate-1000007 . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 7 Source: Maternal Mortality Rate, California and United States; 1991–2008. Available at: http://www.cdph.ca.gov/data/statistics/Documents/MO-CAPAMR-MaternalMortalityRates-USCA-1991-2008.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 8 PAMR. 1999–2008 Florida Pregnancy-Related Mortality Report: Why Are Florida Mothers Continuing to Die?. Available at: http://www.doh.state.fl.us/Family/mch/pamr/1999_2008_pamr_report.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 9 Maryland Department of Health and Mental Hygiene Family Health Administration Center for Maternal and Child Health. Maternal Mortality Review Program. 2010 Annual Report. Available at: http://fha.maryland.gov/pdf/mch/2010MMRrpt.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 10 New York Department of Health. Maternal Mortality Rate Per 100,000 Live Births. Available at: http://www.health.state.ny.us/statistics/chac/birth/matmort.htm . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 11 Texas Department of State Health Services. 2008 Mortality. Available at: http://www.dshs.state.tx.us/CHS/VSTAT/latest/nmortal.shtm . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 12 Pallasmaa N, Ekblad U, Aitokallio-Tallberg A , et al. Cesarean delivery in Finland: maternal complications and obstetric risk factors. Acta Obstet Gynecol Scand 2010; 89: 896-902
    CrossrefPubMedGoogle Scholar
  • 13 Kamilya G, Seal SL, Mukherji J, Bhattacharyya SK, Hazra A. Maternal mortality and cesarean delivery: an analytical observational study. J Obstet Gynaecol Res 2010; 36: 248-253
    CrossrefPubMedGoogle Scholar
  • 14 Quiroz LH, Chang H, Blomquist JL, Okoh YK, Handa VL. Scheduled cesarean delivery: maternal and neonatal risks in primiparous women in a community hospital setting. Am J Perinatol 2009; 26: 271-277
    Article in Thieme ConnectPubMedGoogle Scholar
  • 15 Liu S, Liston RM, Joseph KS, Heaman M, Sauve R, Kramer MS. Maternal Health Study Group of the Canadian Perinatal Surveillance System. Maternal mortality and severe morbidity associated with low-risk planned cesarean delivery versus planned vaginal delivery at term. CMAJ 2007; 176: 455-460
    CrossrefPubMedGoogle Scholar
  • 16 National Institutes of Health state-of-the-science conference statement: Cesarean delivery on maternal request March 27-29, 2006. Obstet Gynecol 2006; 107 (6) 1386-1397
    CrossrefPubMedGoogle Scholar
  • 17 Cunningham FG, Bangdiwala S, Brown SS , et al; National Institutes of Health Consensus Development Conference Panel National Institutes of Health Consensus Development conference statement: vaginal birth after cesarean: new insights March 8–10, 2010. Obstet Gynecol 2010; 115: 1279-1295
    CrossrefPubMedGoogle Scholar
  • 18 Emmons SL, Krohn M, Jackson M, Eschenbach DA. Development of wound infections among women undergoing cesarean section. Obstet Gynecol 1988; 72: 559-564
    PubMedGoogle Scholar
  • 19 Roberts S, Maccato M, Faro S, Pinell P. The microbiology of post-cesarean wound morbidity. Obstet Gynecol 1993; 81: 383-386
    PubMedGoogle Scholar
  • 20 Alanis MC, Villers MS, Law TL, Steadman EM, Robinson CJ. Complications of cesarean delivery in the massively obese parturient. Am J Obstet Gynecol 2010; 203: 271; e1-e7
    PubMedGoogle Scholar
  • 21 Buchholz NP, Daly-Grandeau E, Huber-Buchholz MM. Urological complications associated with caesarean section. Eur J Obstet Gynecol Reprod Biol 1994; 56: 161-163
    CrossrefPubMedGoogle Scholar
  • 22 Cheesman K, Brady JE, Flood P, Li G. Epidemiology of anesthesia-related complications in labor and delivery, New York State, 2002–2005. Anesth Analg 2009; 109: 1174-1181
    CrossrefPubMedGoogle Scholar
  • 23 Mhyre JM. What's new in obstetric anesthesia in 2009? An update on maternal patient safety. Anesth Analg 2010; 111: 1480-1487
    CrossrefPubMedGoogle Scholar
  • 24 American College of Obstetrics and Gynecology. ACOG practice bulletin. Obstetric analgesia and anesthesia. Number 36, July 2002. Int J Gynaecol Obstet 2002; 78: 321-335
    CrossrefPubMedGoogle Scholar
  • 25 Hawkins JL, Chang J, Palmer SK, Gibbs CP, Callaghan WM. Anesthesia-related maternal mortality in the United States: 1979–2002. Obstet Gynecol 2011; 117: 69-74
    CrossrefPubMedGoogle Scholar
  • 26 Loubert C, Hinova A, Fernando R. Update on modern neuraxial analgesia in labour: a review of the literature of the last 5 years. Anaesthesia 2011; 66: 191-212
    CrossrefPubMedGoogle Scholar
  • 27 Ford JB, Roberts CL, Simpson JM, Vaughan JC, Cameron CA. Increased postpartum hemorrhage rates in Australia. Int J Gynaecol Obstet 2007; 98: 237-243
    CrossrefPubMedGoogle Scholar
  • 28 Rossi AC, Lee RH, Chmait RH. Emergency postpartum hysterectomy for uncontrolled postpartum bleeding: a systematic review. Obstet Gynecol 2010; 115: 637-644
    CrossrefPubMedGoogle Scholar
  • 29 Daskalakis G, Anastasakis E, Papantoniou N, Mesogitis S, Theodora M, Antsaklis A. Emergency obstetric hysterectomy. Acta Obstet Gynecol Scand 2007; 86: 223-227
    CrossrefPubMedGoogle Scholar
  • 30 Roopnarinesingh R, Fay L, McKenna P. A 27-year review of obstetric hysterectomy. J Obstet Gynaecol 2003; 23: 252-254
    CrossrefPubMedGoogle Scholar
  • 31 Roberts CL, Algert CS, Knight M, Morris JM. Amniotic fluid embolism in an Australian population-based cohort. BJOG 2010; ; July 7 [Epub ahead of print]
    PubMedGoogle Scholar
  • 32 Knight M, Tuffnell D, Brocklehurst P, Spark P, Kurinczuk JJ. UK Obstetric Surveillance System. Incidence and risk factors for amniotic-fluid embolism. Obstet Gynecol 2010; 115: 910-917
    CrossrefPubMedGoogle Scholar
  • 33 Abenhaim HA, Azoulay L, Kramer MS, Leduc L. Incidence and risk factors of amniotic fluid embolisms: a population-based study on 3 million births in the United States. Am J Obstet Gynecol 2008; 199: 49; e1-e8
    PubMedGoogle Scholar
  • 34 AHRQ Quality Indicators. Rockville MD: : Agency for Healthcare Research and Quality; ; September 2010
    Google Scholar
  • 35 The Joint Commission. Available at: www.jointcommission.org/assets/1/18/VTE_CORE_MEASURE_SET_SELECTION_FORM.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 36 Royal College of Obstetricians and Gynaecologists. Reducing the risk of thrombosis and embolism during pregnancy and the puerperium. Green-top Guideline No. 37. Available at: http://www.rcog.org.uk/files/rcog-corp/GT37ReducingRiskThrombo.pdf . Accessed May 2, 2011
    PubMedGoogle Scholar
  • 37 National Quality Forum. National Quality Forum endorses national consensus standards for perinatal care. Available at: http://www.qualityforum.org/News_And_Resources/Press_Releases/2008/National_Quality_Forum_Endorses_National_Consensus_Standards_for_Perinatal_Care.aspx . Accessed May 2, 2011
    PubMedGoogle Scholar
  • 38 Lang CT, King JC. Maternal mortality in the United States. Best Pract Res Clin Obstet Gynaecol 2008; 22: 517-531
    CrossrefPubMedGoogle Scholar
  • 39 National Vital Statistics Reports. Deaths: final data for 2006. Natl Vital Stat Rep 2009; 57. Available at: http://www.cdc.gov/nchs/data/nvsr/nvsr57/nvsr57_14.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 40 National Vital Statistics Report. Deaths: final data for 2007. Natl Vital Stat Rep 2010; 58. Available at: http://www.cdc.gov/nchs/data/nvsr/nvsr58/nvsr58_19.pdf . Accessed May 1, 2011
    PubMedGoogle Scholar
  • 41 Maryland Department of Health and Mental Hygiene Family Health Administration Center for Maternal and Child Health. Maternal Mortality Review Program. 2010 Annual Report.
    PubMedGoogle Scholar
  • 42 Harper MA, Byington RP, Espeland MA, Naughton M, Meyer R, Lane K. Pregnancy-related death and health care services. Obstet Gynecol 2003; 102: 273-278
    CrossrefPubMedGoogle Scholar
  • 43 Schuitemaker N, van Roosmalen J, Dekker G, van Dongen P, van Geijn H, Gravenhorst JB. Maternal mortality after cesarean section in The Netherlands. Acta Obstet Gynecol Scand 1997; 76: 332-334
    CrossrefPubMedGoogle Scholar
  • 44 Martin JA, Hamilton BE, Sutton PD , et al. Births: final data for 2007. Natl Vital Stat Rep 2010; 58: 1-85
    PubMedGoogle Scholar
  • 45 Ananth CV, Smulian JC, Vintzileos AM. The association of placenta previa with history of cesarean delivery and abortion: a metaanalysis. Am J Obstet Gynecol 1997; 177: 1071-1078
    CrossrefPubMedGoogle Scholar
  • 46 Lydon-Rochelle M, Holt VL, Easterling TR, Martin DP. First-birth cesarean and placental abruption or previa at second birth(1). Obstet Gynecol 2001; 97 (5 Pt 1) 765-769
    CrossrefPubMedGoogle Scholar
  • 47 Silver RM, Landon MB, Rouse DJ , et al; National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network Maternal morbidity associated with multiple repeat cesarean deliveries. Obstet Gynecol 2006; 107: 1226-1232
    CrossrefPubMedGoogle Scholar
  • 48 Hemminki E. Impact of caesarean section on future pregnancy—a review of cohort studies. Paediatr Perinat Epidemiol 1996; 10: 366-379
    CrossrefPubMedGoogle Scholar
  • 49 Silver RM. Delivery after previous cesarean: long-term maternal outcomes. Semin Perinatol 2010; 34: 258-266
    CrossrefPubMedGoogle Scholar
  • 50 Oral E, Elter K. The impact of cesarean birth on subsequent fertility. Curr Opin Obstet Gynecol 2007; 19: 238-243
    CrossrefPubMedGoogle Scholar
  • 51 Kennare R, Tucker G, Heard A, Chan A. Risks of adverse outcomes in the next birth after a first cesarean delivery. Obstet Gynecol 2007; 109 (2 Pt 1) 270-276
    CrossrefPubMedGoogle Scholar
  • 52 Smith GC, Pell JP, Dobbie R. Caesarean section and risk of unexplained stillbirth in subsequent pregnancy. Lancet 2003; 362: 1779-1784
    CrossrefPubMedGoogle Scholar
  • 53 Chongsuvivatwong V, Bachtiar H, Chowdhury ME , et al. Maternal and fetal mortality and complications associated with cesarean section deliveries in teaching hospitals in Asia. J Obstet Gynaecol Res 2010; 36: 45-51
    CrossrefPubMedGoogle Scholar
  • 54 Farrell SA, Allen VM, Baskett TF. Parturition and urinary incontinence in primiparas. Obstet Gynecol 2001; 97: 350-356
    CrossrefPubMedGoogle Scholar
  • 55 Hannah ME, Hannah WJ, Hodnett ED , et al; Term Breech Trial 3-Month Follow-up Collaborative Group Outcomes at 3 months after planned cesarean vs planned vaginal delivery for breech presentation at term: the international randomized Term Breech Trial. JAMA 2002; 287: 1822-1831
    CrossrefPubMedGoogle Scholar
  • 56 Turner CE, Young JM, Solomon MJ, Ludlow J, Benness C. Incidence and etiology of pelvic floor dysfunction and mode of delivery: an overview. Dis Colon Rectum 2009; 52: 1186-1195
    CrossrefPubMedGoogle Scholar
  • 57 MacLennan AH, Taylor AW, Wilson DH, Wilson D. The prevalence of pelvic floor disorders and their relationship to gender, age, parity and mode of delivery. BJOG 2000; 107: 1460-1470
    CrossrefPubMedGoogle Scholar
  • 58 Nygaard IE, Rao SS, Dawson JD. Anal incontinence after anal sphincter disruption: a 30-year retrospective cohort study. Obstet Gynecol 1997; 89: 896-901
    CrossrefPubMedGoogle Scholar
  • 59 Hannah ME, Whyte H, Hannah WJ , et al. Term Breech Trial Collaborative Group. Maternal outcomes at 2 years after planned cesarean vs planned vaginal birth for breech presentation at term: the international randomized Term Breech Trial. Am J Obstet Gynecol 2004; 191: 917-927
    CrossrefPubMedGoogle Scholar
  • 60 Buchsbaum GM, Chin M, Glantz C, Guzick D. Prevalence of urinary incontinence and associated risk factors in a cohort of nuns. Obstet Gynecol 2002; 100: 226-229
    CrossrefPubMedGoogle Scholar
  • 61 Connolly TJ, Litman HJ, Tennstedt SL, Link CL, McKinlay JB. The effect of mode of delivery, parity, and birth weight on risk of urinary incontinence. Int Urogynecol J Pelvic Floor Dysfunct 2007; 18: 1033-1042
    PubMedGoogle Scholar
  • 62 Goldstein SR. The role of transvaginal ultrasound or endometrial biopsy in the evaluation of the menopausal endometrium. Am J Obstet Gynecol 2009; 201: 5-11
    CrossrefPubMedGoogle Scholar
  • 63 Wax JR, Herson V, Carignan E, Mather J, Ingardia CJ. Contribution of elective delivery to severe respiratory distress at term. Am J Perinatol 2002; 19: 81-86
    Article in Thieme ConnectPubMedGoogle Scholar
  • 64 Hook B, Kiwi R, Amini SB, Fanaroff A, Hack M. Neonatal morbidity after elective repeat cesarean section and trial of labor. Pediatrics 1997; 100 (3 Pt 1) 348-353
    CrossrefPubMedGoogle Scholar
  • 65 Zanardo V, Simbi AK, Franzoi M, Soldà G, Salvadori A, Trevisanuto D. Neonatal respiratory morbidity risk and mode of delivery at term: influence of timing of elective caesarean delivery. Acta Paediatr 2004; 93: 643-647
    Google Scholar
  • 66 Bailit JL, Gregory KD, Reddy UM , et al. Maternal and neonatal outcomes by labor onset type and gestational age. Am J Obstet Gynecol 2010; 202: 245; e1-e245, e12
    PubMedGoogle Scholar
  • 67 Morrison JJ, Rennie JM, Milton PJ. Neonatal respiratory morbidity and mode of delivery at term: influence of timing of elective caesarean section. Br J Obstet Gynaecol 1995; 102: 101-106
    CrossrefPubMedGoogle Scholar
  • 68 Zanardo V, Nicolussi S, Carlo G , et al. Beta endorphin concentrations in human milk. J Pediatr Gastroenterol Nutr 2001; 33: 160-164
    CrossrefPubMedGoogle Scholar
  • 69 Wax JR, Cartin A, Pinette MG, Blackstone J. Patient choice cesarean: an evidence-based review. Obstet Gynecol Surv 2004; 59: 601-616
    CrossrefPubMedGoogle Scholar
  • 70 Laubereau B, Filipiak-Pittroff B, von Berg A, Grubl A, Reinhardt D, Wichmann HE , et al, for the GINI Study Group Cesarean section and gastrointestinal symptoms, atopic dermatitis, and sensation during the first year of life. Arch Dis Child 2004; 89: 993-997
    CrossrefPubMedGoogle Scholar
  • 71 Biasucci G, Benenati B, Morelli L, Bessi E, Boehm G. Cesarean delivery may affect the early biodiversity of intestinal bacteria. J Nutr 2008; 138: 1796S-1800S
    PubMedGoogle Scholar
  • 72 Dominguez-Bello MG, Costello EK, Contreras M , et al. Delivery mode shapes the acquisition and structure of the initial microbiota across multiple body habitats in newborns. Proc Natl Acad Sci U S A 2010; 107: 11971-11975
    CrossrefPubMedGoogle Scholar
  • 73 Huurre A, Kalliomäki M, Rautava S, Rinne M, Salminen S, Isolauri E. Mode of delivery—effects on gut microbiota and humoral immunity. Neonatology 2008; 93: 236-240
    CrossrefPubMedGoogle Scholar
  • 74 Grönlund MM, Lehtonen OP, Eerola E, Kero P. Fecal microflora in healthy infants born by different methods of delivery: permanent changes in intestinal flora after cesarean delivery. J Pediatr Gastroenterol Nutr 1999; 28: 19-25
    CrossrefPubMedGoogle Scholar
  • 75 Eggesbø M, Botten G, Stigum H, Nafstad P, Magnus P. Is delivery by cesarean section a risk factor for food allergy?. J Allergy Clin Immunol 2003; 112: 420-426
    CrossrefPubMedGoogle Scholar
  • 76 Negele K, Heinrich J, Borte M , et al; LISA Study Group Mode of delivery and development of atopic disease during the first 2 years of life. Pediatr Allergy Immunol 2004; 15: 48-54
    CrossrefPubMedGoogle Scholar
  • 77 Renz-Polster H, David MR, Buist AS , et al. Caesarean section delivery and the risk of allergic disorders in childhood. Clin Exp Allergy 2005; 35: 1466-1472
    CrossrefPubMedGoogle Scholar
  • 78 Koplin J, Allen K, Gurrin L, Osborne N, Tang ML, Dharmage S. Is caesarean delivery associated with sensitization to food allergens and IgE-mediated food allergy: a systematic review. Pediatr Allergy Immunol 2008; 19: 682-687
    CrossrefPubMedGoogle Scholar
  • 79 Acker DB, Sachs BP, Friedman EA. Risk factors for shoulder dystocia in the average-weight infant. Obstet Gynecol 1986; 67: 614-618
    CrossrefPubMedGoogle Scholar
  • 80 Gross SJ, Shime J, Farine D. Shoulder dystocia: predictors and outcome. A five-year review. Am J Obstet Gynecol 1987; 156: 334-336
    CrossrefPubMedGoogle Scholar
  • 81 Nocon JJ, McKenzie DK, Thomas LJ, Hansell RS. Shoulder dystocia: an analysis of risks and obstetric maneuvers. Am J Obstet Gynecol 1993; 168 (6 Pt 1) 1732-1737; discussion 1737–1739
    CrossrefPubMedGoogle Scholar
  • 82 Baskett TF, Allen AC. Perinatal implications of shoulder dystocia. Obstet Gynecol 1995; 86: 14-17
    CrossrefPubMedGoogle Scholar
  • 83 McFarland LV, Raskin M, Daling JR, Benedetti TJ. Erb/Duchenne's palsy: a consequence of fetal macrosomia and method of delivery. Obstet Gynecol 1986; 68: 784-788
    PubMedGoogle Scholar
  • 84 Dunn DW, Engle WA. Brachial plexus palsy: intrauterine onset. Pediatr Neurol 1985; 1: 367-369
    CrossrefPubMedGoogle Scholar
  • 85 Koenigsberger MR. Brachial plexus palsy at birth: intrauterine or due to birth trauma?. Ann Neurol 1980; 8: 228-230
    PubMedGoogle Scholar
  • 86 Landon MB, Hauth JC, Leveno KJ , et al; National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery. N Engl J Med 2004; 351: 2581-2589
    CrossrefPubMedGoogle Scholar
  • 87 American College of Obstetricians and Gynecologists Committee on ethics: Committee Opinion #321: Maternal decision making, ethics and the law. Obstet Gynecol 2005; 106: 1127-1137
    CrossrefPubMedGoogle Scholar
  • 88 Chervenak FA, McCullough LB. Neglected ethical dimensions of the professional liability crisis. Am J Obstet Gynecol 2004; 190: 1198-1200
    CrossrefPubMedGoogle Scholar
  • 89 Lyerly AD, Little MO. Toward an ethically responsible approach to vaginal birth after cesarean. Semin Perinatol 2010; 34: 337-344
    CrossrefPubMedGoogle Scholar
  • 90 Rybak EA. Hippocratic ideal, Faustian bargain and Damocles' sword: erosion of patient autonomy in obstetrics. J Perinatol 2009; 29: 721-725
    CrossrefPubMedGoogle Scholar
  • 91 Smith GCS. Life-table analysis of the risk of perinatal death at term and post term in singleton pregnancies. Am J Obstet Gynecol 2001; 184: 489-496
    CrossrefPubMedGoogle Scholar
  • 92 Gregory KD, Fridman M, Shah S, Korst LM. Global measures of quality- and patient safety-related childbirth outcomes: should we monitor adverse or ideal rates?. Am J Obstet Gynecol 2009; 200: 681; e1-e7
    PubMedGoogle Scholar