The 3G Multigenerational Cohort of Nova Scotian women and their mothers and offspring.

BACKGROUND: The negative impact of exposures such as maternal obesity, excessive gestational weight gain, and hypertension in pregnancy on the health of the next generation has been well studied. Evidence from animal studies suggests that the effects of in utero exposures may persist into the second generation, but the epidemiological literature on the influence of pregnancy-related exposures across three generations in humans is sparse. OBJECTIVES: This cohort was established to investigate associations between antenatal and perinatal exposures and health outcomes in women and their offspring. POPULATION: The cohort includes women who were born and subsequently had their own pregnancies in the Canadian province of Nova Scotia from 1980 onward. DESIGN: Intergenerational linkage of data in the Nova Scotia Atlee Perinatal Database was used to establish a population-based dynamic retrospective cohort. METHODS: The cohort has prospectively collected information on sociodemographics, maternal health and health behaviours, pregnancy health and complications, and obstetrical and neonatal outcomes for two generations of women and their offspring. PRELIMINARY RESULTS: As of October 2018, the 3G cohort included 14 978 grandmothers (born 1939-1986), 16 766 mothers or cohort women (born 1981-2003), and 28 638 children (born 1996-2018). The cohort women were generally younger than Nova Scotian women born after 1980, and as a result, characteristics associated with pregnancy at a younger age were more frequently seen in the cohort women; sampling weights will be created to account for this design effect. The cohort will be updated annually to capture future deliveries to women who are already in the cohort and women who become eligible for inclusion when they deliver their first child. CONCLUSIONS: The 3G Multigenerational Cohort is a population-based cohort of women and their mothers and offspring, spanning a time period of 38 years, and provides the opportunity to study inter- and transgenerational associations across the maternal line.

No. 298-The Prevention of Early-Onset Neonatal Group B Streptococcal Disease.

OBJECTIVE: To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes. OUTCOMES: Maternal outcomes evaluated included exposure to antibiotics in pregnancy and labour and complications related to antibiotic use. Neonatal outcomes of rates of early-onset group B streptococcal infections are evaluated. EVIDENCE: Published literature was retrieved through searches of MEDLINE, CINAHL, and The Cochrane Library from January 1980 to July 2012 using appropriate controlled vocabulary and key words (group B streptococcus, antibiotic therapy, infection, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: The recommendations in this guideline are designed to help clinicians identify and manage pregnancies at risk for neonatal group B streptococcal disease to optimize maternal and perinatal outcomes. No cost-benefit analysis is provided. SUMMARY STATEMENT: There is good evidence based on randomized control trial data that in women with pre-labour rupture of membranes at term who are colonized with group B streptococcus, rates of neonatal infection are reduced with induction of labour (I). There is no evidence to support safe neonatal outcomes with expectant management in this clinical situation.

No. 276-Management of Group B Streptococcal Bacteriuria in Pregnancy.

OBJECTIVE: To provide information regarding the management of group B streptococcal (GBS) bacteriuria to midwives, nurses, and physicians who are providing obstetrical care. OUTCOMES: The outcomes considered were neonatal GBS disease, preterm birth, pyelonephritis, chorioamnionitis, and recurrence of GBS colonization. EVIDENCE: Medline, PubMed, and the Cochrane database were searched for articles published in English to December 2010 on the topic of GBS bacteriuria in pregnancy. Bacteriuria is defined in this clinical practice guideline as the presence of bacteria in urine, regardless of the number of colony-forming units per mL (CFU/mL). Low colony counts refer to <100 000 CFU/mL, and high (significant) colony counts refer to ≥100 000 CFU/mL. Results were restricted to systematic reviews, randomized controlled trials, and relevant observational studies. Searches were updated on a regular basis and incorporated in the guideline to February 2011. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: Recommendations were quantified using the evaluation of evidence guidelines developed by the Canadian Task Force on Preventive Health Care (Table). BENEFITS, HARMS, AND COSTS: The recommendations in this guideline are designed to help clinicians identify pregnancies in which it is appropriate to treat GBS bacteriuria to optimize maternal and perinatal outcomes, to reduce the occurrences of antibiotic anaphylaxis, and to prevent increases in antibiotic resistance to GBS and non-GBS pathogens. No cost-benefit analysis is provided.

The Prevention of Early-Onset Neonatal Group B Streptococcal Disease.

OBJECTIVE: To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes. OUTCOMES: Maternal outcomes evaluated included exposure to antibiotics in pregnancy and labour and complications related to antibiotic use. Neonatal outcomes of rates of early-onset group B streptococcal infections are evaluated. EVIDENCE: Published literature was retrieved through searches of MEDLINE, CINAHL, and The Cochrane Library from January 1980 to July 2012 using appropriate controlled vocabulary and key words (group B streptococcus, antibiotic therapy, infection, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: The recommendations in this guideline are designed to help clinicians identify and manage pregnancies at risk for neonatal group B streptococcal disease to optimize maternal and perinatal outcomes. No cost-benefit analysis is provided. SUMMARY STATEMENT: There is good evidence based on randomized control trial data that in women with pre-labour rupture of membranes at term who are colonized with group B streptococcus, rates of neonatal infection are reduced with induction of labour (I). There is no evidence to support safe neonatal outcomes with expectant management in this clinical situation.

Effects of socioeconomic position and clinical risk factors on spontaneous and iatrogenic preterm birth.

BACKGROUND: The literature shows a variable and inconsistent relationship between socioeconomic position and preterm birth. We examined risk factors for spontaneous and iatrogenic preterm birth, with a focus on socioeconomic position and clinical risk factors, in order to explain the observed inconsistency. METHODS: We carried out a retrospective population-based cohort study of all singleton deliveries in Nova Scotia from 1988 to 2003. Data were obtained from the Nova Scotia Atlee Perinatal Database and the federal income tax T1 Family Files. Separate logistic models were used to quantify the association between socioeconomic position, clinical risk factors and spontaneous preterm birth and iatrogenic preterm birth. RESULTS: The study population included 132,714 singleton deliveries and the rate of preterm birth was 5.5%. Preterm birth rates were significantly higher among the women in the lowest (versus the highest) family income group for spontaneous (rate ratio 1.14, 95% confidence interval (CI) 1.03, 1.25) but not iatrogenic preterm birth (rate ratio 0.95, 95% CI 0.75, 1.19). Adjustment for maternal characteristics attenuated the family income-spontaneous preterm birth relationship but strengthened the relationship with iatrogenic preterm birth. Clinical risk factors such as hypertension were differentially associated with spontaneous (rate ratio 3.92, 95% CI 3.47, 4.44) and iatrogenic preterm (rate ratio 14.1, 95% CI 11.4, 17.4) but factors such as diabetes mellitus were not (rate ratio 4.38, 95% CI 3.21, 5.99 for spontaneous and 4.02, 95% CI 2.07, 7.80 for iatrogenic preterm birth). CONCLUSIONS: Socioeconomic position and clinical risk factors have different effects on spontaneous and iatrogenic preterm. Recent temporal increases in iatrogenic preterm birth appear to be responsible for the inconsistent relationship between socioeconomic position and preterm birth.

The prevention of early-onset neonatal group B streptococcal disease.

OBJECTIVE: To review the evidence in the literature and to provide recommendations on the management of pregnant women in labour for the prevention of early-onset neonatal group B streptococcal disease. The key revisions in this updated guideline include changed recommendations for regimens for antibiotic prophylaxis, susceptibility testing, and management of women with pre-labour rupture of membranes. OUTCOMES: Maternal outcomes evaluated included exposure to antibiotics in pregnancy and labour and complications related to antibiotic use. Neonatal outcomes of rates of early-onset group B streptococcal infections are evaluated. EVIDENCE: Published literature was retrieved through searches of MEDLINE, CINAHL, and The Cochrane Library from January 1980 to July 2012 using appropriate controlled vocabulary and key words (group B streptococcus, antibiotic therapy, infection, prevention). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date or language restrictions. Searches were updated on a regular basis and incorporated in the guideline to May 2013. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: The recommendations in this guideline are designed to help clinicians identify and manage pregnancies at risk for neonatal group B streptococcal disease to optimize maternal and perinatal outcomes. No cost-benefit analysis is provided. SUMMARY STATEMENT: There is good evidence based on randomized control trial data that in women with pre-labour rupture of membranes at term who are colonized with group B streptococcus, rates of neonatal infection are reduced with induction of labour. (I) There is no evidence to support safe neonatal outcomes with expectant management in this clinical situation. RECOMMENDATIONS: 1. Offer all women screening for colonization with group B streptococcus at 35 to 37 weeks' gestation with culture taken from one swab first to the vagina and then to the rectum (through the anal sphincter). (II-1A) This includes women with planned Caesarean delivery because of their risk of labour or ruptured membranes earlier than the scheduled Caesarean delivery. (II-2B) 2. Because of the association of heavy colonization with early onset neonatal disease, provide intravenous antibiotic prophylaxis for group B streptococcus at the onset of labour or rupture of the membranes to: • any woman positive for group B streptococcus by vaginal/rectal swab culture screening done at 35 to 37 weeks' gestation (II-2B); • any woman with an infant previously infected with group B streptococcus (II-3B); • any woman with documented group B streptococcus bacteriuria (regardless of level of colony-forming units) in the current pregnancy. (II-2A) 3. Manage all women who are < 37 weeks' gestation and in labour or with rupture of membranes with intravenous group B streptococcus antibiotic prophylaxis for a minimum of 48 hours, unless there has been a negative vaginal/rectal swab culture or rapid nucleic acid-based test within the previous 5 weeks. (II-3A) 4. Treat all women with intrapartum fever and signs of chorioamnionitis with broad spectrum intravenous antibiotics targeting chorioamnionitis and including coverage for group B streptococcus, regardless of group B streptococcus status and gestational age. (II-2A) 5. Request antibiotic susceptibility testing on group B streptococcus-positive urine and vaginal/rectal swab cultures in women who are thought to have a significant risk of anaphylaxis from penicillin. (II-1A) 6. If a woman with pre-labour rupture of membranes at ≥ 37 weeks' gestation is positive for group B streptococcus by vaginal/rectal swab culture screening, has had group B streptococcus bacteriuria in the current pregnancy, or has had an infant previously affected by group B streptococcus disease, administer intravenous group B streptococcus antibiotic prophylaxis. Immediate obstetrical delivery (such as induction of labour) is indicated, as described in the Induction of Labour guideline published by the Society of Obstetricians and Gynaecologist in September 2013. (II-2B) 7. At ≥ 37 weeks' gestation, if group B streptococcus colonization status is unknown and the 35- to 37-week culture was not performed or the result is unavailable and the membranes have been ruptured for greater than 18 hours, administer intravenous group B streptococcus antibiotic prophylaxis. (II-2B) 8. If a woman with pre-labour rupture of membranes at < 37 weeks' gestation has an unknown or positive group B streptococcus culture status, administer intravenous group B streptococcus prophylaxis for 48 hours, as well as other antibiotics if indicated, while awaiting spontaneous or obstetrically indicated labour. (II-3B).

Objectif : Analyser les données issues de la littérature et formuler des recommandations sur la prise en charge des parturientes en vue de prévenir l'infection néonatale à streptocoques du groupe B d'apparition précoce. Parmi les révisions clés que renferme la présente directive clinique mise à jour, on trouve des modifications quant aux recommandations en ce qui concerne les schémas posologiques d'antibioprophylaxie, les épreuves de sensibilité et la prise en charge des femmes présentant une rupture prématurée des membranes. Issues : Parmi les issues maternelles évaluées, on trouvait l'exposition aux antibiotiques au cours de la grossesse et du travail, ainsi que les complications associées à l'administration d'antibiotiques. Les issues néonatales associées aux taux d'infection néonatale à streptocoques du groupe B d'apparition précoce ont été évaluées. Résultats : La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans PubMed, CINAHL et The Cochrane Library entre janvier 1980 et juillet 2012, au moyen d'un vocabulaire contrôlé et de mots clés appropriés (« Group B streptococcus ¼, « antibiotic therapy ¼, « infection ¼, « prevention ¼). Les résultats ont été restreints aux analyses systématiques, aux essais comparatifs randomisés / essais cliniques comparatifs et aux études observationnelles. Aucune restriction n'a été appliquée en matière de date ou de langue. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en mai 2013. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. Valeurs : La qualité des résultats est évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau). Avantages, désavantages et coûts : Les recommandations que renferme la présente directive clinique sont conçues de façon à aider les cliniciens à identifier et à assurer la prise en charge des grossesses exposées à un risque d'infection néonatale à streptocoques du groupe B, en vue d'optimiser les issues maternelles et périnatales. Aucune analyse de rentabilité n'est fournie. Déclaration sommaire Nous disposons de bonnes données (issues d'essais comparatifs randomisés) indiquant que, chez les femmes présentant une rupture prématurée des membranes à terme qui sont colonisées par des streptocoques du groupe B, le déclenchement du travail entraîne une baisse des taux d'infection néonatale. (I) Aucune donnée ne permet de soutenir que, dans une telle situation clinique, la prise en charge non interventionniste permet l'obtention de bonnes issues néonatales. Recommandations 1. Offrir, à toutes les femmes, un dépistage de la colonisation par des streptocoques du groupe B à 35 - 37 semaines de gestation au moyen d'une mise en culture effectuée à partir d'un écouvillonnage du vagin, en premier lieu, et du rectum par la suite (au-delà du sphincter anal). (II-1A) Cette approche s'applique également aux femmes chez qui une césarienne est planifiée, et ce, en raison de leur risque de connaître un travail ou une rupture des membranes avant la date prévue de la césarienne. (II-2B) 2. En raison de l'association entre une forte colonisation et l'infection néonatale d'apparition précoce, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B dans les cas suivants, au moment de l'apparition du travail ou de la rupture des membranes : • toutes les femmes ayant obtenu des résultats positifs (indiquant la présence de streptocoques du groupe B) dans le cadre du dépistage par mise en culture d'un écouvillonnage vaginal / rectal mené à 35 - 37 semaines de gestation (II-2B); • toute femme ayant déjà accouché d'un enfant présentant une infection à streptocoques du groupe B (II-3B); • toute femme ayant présenté une bactériurie à streptocoques du groupe B documentée (peu importe le taux d'unités formatrices de colonies) dans le cadre de la grossesse en cours (II-2A). 3. Administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B pendant un minimum de 48 heures à toutes les femmes se trouvant à < 37 semaines de gestation et connaissant un travail ou une rupture des membranes, sauf lorsqu'un résultat négatif a été obtenu au cours des cinq semaines précédentes dans le cadre d'un test rapide fondé sur les acides nucléiques ou d'un dépistage par mise en culture d'un écouvillonnage vaginal / rectal. (II-3A) 4. Administrer (par voie intraveineuse) des antibiotiques à large spectre ciblant la chorioamnionite et les streptocoques du groupe B à toutes les femmes qui présentent une fièvre intrapartum et des symptômes de chorioamnionite (sans égard à l'âge gestationnel ni à l'état quant aux streptocoques du groupe B). (II-2A) 5. Demander la tenue d'une épreuve de sensibilité aux antibiotiques chez les femmes qui ont obtenu des résultats positifs en ce qui concerne la présence de streptocoques du groupe B, à la suite d'un dépistage urinaire et de la mise en culture d'un écouvillonnage vaginal/rectal, et que l'on soupçonne être exposées à un risque considérable d'anaphylaxie attribuable à la pénicilline. (II-1A) 6. Lorsqu'une femme présentant une rupture prématurée des membranes à ≥ 37 semaines de gestation obtient des résultats positifs (au dépistage par mise en culture d'un écouvillonnage vaginal / rectal) indiquant la présence de streptocoques du groupe B, qu'elle a connu une bactériurie à streptocoques du groupe B pendant la grossesse en cours ou qu'elle a déjà accouché d'un enfant atteint d'une infection à streptocoques du groupe B, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B. La tenue immédiate d'un accouchement obstétrical (tel que le déclenchement du travail) s'avère indiquée, comme le décrit la directive clinique intitulée « Déclenchement du travail ¼ qui a été publiée par la Société des obstétriciens et gynécologues du Canada en septembre 2013. (II-2B) 7. À ≥ 37 semaines de gestation, lorsque le statut quant à la colonisation par des streptocoques du groupe B est inconnu, qu'une mise en culture n'a pas été menée à 35 - 37 semaines de gestation (ou que les résultats d'une telle mise en culture ne sont pas disponibles) et que les membranes sont rompues depuis plus de 18 heures, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B. (II-2B) 8. Lorsque, chez une femme présentant une rupture prématurée des membranes à < 37 semaines de gestation, les résultats du dépistage des streptocoques du groupe B par mise en culture sont inconnus ou positifs, administrer une antibioprophylaxie intraveineuse visant les streptocoques du groupe B pendant 48 heures, ainsi que d'autres antibiotiques lorsque cela s'avère indiqué, en attendant la mise en œuvre spontanée ou obstétricalement indiquée du travail. (II-3B).

Management of group B streptococcal bacteriuria in pregnancy.

OBJECTIVE: To provide information regarding the management of group B streptococcal (GBS) bacteriuria to midwives, nurses, and physicians who are providing obstetrical care. OUTCOMES: The outcomes considered were neonatal GBS disease, preterm birth, pyelonephritis, chorioamnionitis, and recurrence of GBS colonization. EVIDENCE: Medline, PubMed, and the Cochrane database were searched for articles published in English to December 2010 on the topic of GBS bacteriuria in pregnancy. Bacteriuria is defined in this clinical practice guideline as the presence of bacteria in urine, regardless of the number of colony-forming units per mL (CFU/mL). Low colony counts refer to < 100 000 CFU/mL, and high (significant) colony counts refer to ≥ 100 000 CFU/mL. Results were restricted to systematic reviews, randomized controlled trials, and relevant observational studies. Searches were updated on a regular basis and incorporated in the guideline to February 2011. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: Recommendations were quantified using the evaluation of evidence guidelines developed by the Canadian Task Force on Preventive Health Care (Table). BENEFITS, HARMS, AND COSTS: The recommendations in this guideline are designed to help clinicians identify pregnancies in which it is appropriate to treat GBS bacteriuria to optimize maternal and perinatal outcomes, to reduce the occurrences of antibiotic anaphylaxis, and to prevent increases in antibiotic resistance to GBS and non-GBS pathogens. No cost-benefit analysis is provided. RECOMMENDATIONS: 1. Treatment of any bacteriuria with colony counts ≥ 100 000 CFU/mL in pregnancy is an accepted and recommended strategy and includes treatment with appropriate antibiotics. (II-2A) 2. Women with documented group B streptococcal bacteriuria (regardless of level of colony-forming units per mL) in the current pregnancy should be treated at the time of labour or rupture of membranes with appropriate intravenous antibiotics for the prevention of early-onset neonatal group B streptococcal disease. (II-2A) 3. Asymptomatic women with urinary group B streptococcal colony counts < 100 000 CFU/mL in pregnancy should not be treated with antibiotics for the prevention of adverse maternal and perinatal outcomes such as pyelonephritis, chorioamnionitis, or preterm birth. (II-2E) 4. Women with documented group B streptococcal bacteriuria should not be re-screened by genital tract culture or urinary culture in the third trimester, as they are presumed to be group B streptococcal colonized. (II-2D).

Recent changes in maternal characteristics by socioeconomic status.

OBJECTIVE: To describe changes in maternal characteristics by socioeconomic status, in order to provide a context for recent changes in the frequency of obstetric procedures and outcomes, and information for health planning purposes. METHODS: All NS residents who delivered between 1988 and 2007 were included in the study. Information on maternal characteristics was obtained from the Nova Scotia Atlee Perinatal Database, and socioeconomic status information was obtained through a confidential link with federal income tax T1 Family Files (1988 to 2003). RESULTS: Total births to women < 20 years of age were high (31.5% in 2003) and increased in the lowest family income group between 1988 and 2003, while rates were low (0.7% in 2003) and decreased in the highest family income group. Total births to women >/= 35 years increased by 136% (95% CI 122, 150) between 1988-89 and 2006-07. Births to women with a weight >/= 90 kg also increased, while those to smokers decreased in all socioeconomic groups. The proportion of births to multiparous women with a previous low birth weight infant did not change (-5 %, 95% CI -14, 6), although births to women with a previous perinatal death declined by 52% (95% CI -60,-42). CONCLUSION: Large secular changes have occurred in maternal characteristics over the past two decades, and the magnitude of these changes has differed by socioeconomic status.

Cumulative economic implications of initial method of delivery.

OBJECTIVE: To examine the cumulative costs of hospital care in the first and subsequent pregnancies associated with different methods in the initial delivery of nulliparous women. METHODS: An 18-year population-based cohort study (1985-2002) using the Nova Scotia Atlee Perinatal Database compared cumulative delivery costs in the first and subsequent pregnancies. Women were identified by initial method of delivery for nulliparous women with singleton cephalic presentation at term undergoing spontaneous or induced labor for planned vaginal delivery, and for nulliparous women undergoing cesarean delivery without labor. Costs that were assessed included nursing hours in antepartum, labor and delivery, postpartum and neonatal intensive care units, physician costs, labor induction agents, consumables, and costs for postpartum hysterectomy, tubal ligation, and dilatation and curettage. RESULTS: A total of 27,613 pregnancies satisfied inclusion and exclusion criteria. When cumulative costs by type of labor at first delivery were considered, induction of labor (7,220 dollars) was more costly than spontaneous onset of labor (6,919 dollars, P = .006). The cumulative costs of assisted vaginal delivery at first delivery (7,288 dollars) and cesarean delivery in labor at first delivery (9,524 dollars) were similar in magnitude and were higher than spontaneous vaginal delivery at first delivery (P < .001). Cesarean delivery in labor in the first delivery was the most costly type of delivery (9,524 dollars), and the differences in cost increased with increasing number of deliveries (P < .05). CONCLUSION: Cesarean delivery in labor in the first delivery is associated with increased cumulative costs compared with other methods of delivery, regardless of the number or type of subsequent deliveries.

Economic implications of method of delivery.

OBJECTIVE: This study was undertaken to examine the costs of hospital care associated with different methods of delivery. STUDY DESIGN: An 18-year population-based cohort study (1985-2002) using the Nova Scotia Atlee Perinatal Database compared outcomes in nulliparous women at term undergoing spontaneous or induced labor for planned vaginal delivery, or undergoing cesarean delivery without labor. Costs that were assessed included physician fees, nursing hours in the labor and delivery, postpartum and neonatal intensive care units, epidural use, induction of labor agents, and consumables. RESULTS: A total of 27,614 pregnancies satisfied inclusion and exclusion criteria, 5233 of which had labor induced. A comparison of mean costs per mother/infant pair demonstrated that cesarean delivery in labor ($2137) was increased compared with spontaneous vaginal delivery ($1340, P=.01), assisted vaginal delivery ($1594, P=.01), and cesarean delivery without labor ($1532, P=.01). The cost of delivery after induction of labor ($1715) was increased compared with spontaneous onset of labor ($1474, P<.001). CONCLUSION: Cesarean delivery in labor occurs more frequently with labor induction and is associated with increased costs compared with other methods of delivery.