Yanfang Guo

Examining Caesarean Section Rates in Canada Using the Robson Classification System

OBJECTIVE To determine the groups within the obstetric population contributing most substantially to the Caesarean section rate in five Canadian provinces. METHODS Hospital births from five participating provinces were grouped into Robsons 10 mutually exclusive and totally inclusive classification categories. The relative contribution of each group to the overall CS rate, relative size of group, and CS rate were calculated for British Columbia, Alberta, Ontario, Nova Scotia, and Newfoundland and Labrador for the four-year period from 2007-2008 to 2010-2011. RESULTS In all five provinces (accounting for approximately 64% of births in Canada), and for all years examined, the group making the largest relative contribution to the CS rate was women with at least one previous CS and a term, singleton, cephalic-presenting pregnancy (Robson Group 5). The CS rate for this group ranged from 76.1% in Alberta to 89.9% in Newfoundland and Labrador in 2010 to 2011, accounting for 11.3% of all deliveries. The rate of CS for Group 5 decreased slightly over the four years, except in Ontario. The next largest contributing group was nulliparous women with a term, singleton, cephalic-presenting pregnancy. Those with induced labour or Caesarean section before labour (Robson Group 2) had CS rates ranging from 34.4% in Nova Scotia to 44.6% in British Columbia (accounting for 13.1% of all deliveries), and those with spontaneous onset of labour (Robson Group 1) had CS rates of 14.5% to 20.3% in 2010 to 2011 (accounting for 23.6% of all deliveries). CONCLUSION All hospitals and health authorities can use this standardized classification system as part of a quality improvement initiative to monitor Caesarean section rates. This classification system identifies relevant areas for interventions and resources to reduce rates of Caesarean section.

Maternal exposure to moderate ambient carbon monoxide is associated with decreased risk of preeclampsia

OBJECTIVE Carbon monoxide (CO) in cigarette smoke may be the mechanism by which tobacco use during pregnancy decreases the risk of the development of preeclampsia. We attempted to test this hypothesis by examining the effect of maternal exposure to ambient CO on preeclampsia. STUDY DESIGN Births that occurred between 2004 and 2009 in the Canadian province of Ontario were extracted from the data. Study subjects were divided into 4 groups according to quartiles of CO concentration that were based on maternal residence. Adjusted odds ratio and 95% confidence interval were used to estimate the independent effect of CO on preeclampsia. RESULTS Rates of preeclampsia were 2.32%, 1.97%, 1.59%, and 1.26%, respectively, in the first, second, third, and fourth quartile of CO concentration. The inverse association between CO concentration and preeclampsia risk remained the same after adjustment for several important confounding factors. CONCLUSION Maternal exposure to moderate ambient CO is associated independently with a decreased risk of preeclampsia.

Infant sex, family support and postpartum depression in a Chinese cohort

Objectives To assess the impact of prenatal and postnatal family support on the association between infant sex and postpartum depression (PPD). Design Prospective cohort study. Setting Pregnant women seen at Hunan Maternal and Infant Hospital, the First Affiliated and the Third Affiliated Hospitals of the Central South University in Changsha, Hunan, Peoples Republic of China from February to September 2007. Participants 534 Pregnant women who were consecutively recruited from the participating hospital during their prenatal visits at 30–32 weeks of gestation and who completed the 2 weeks postpartum survey, with no recorded major psychiatric disorders and obstetric and/or pregnancy complications. Main outcome measure PPD, which was defined as a score of 13 or higher of the Edinburgh Postnatal Depression Scale. Results Postnatal family support scores were much lower in women who gave birth to a female infant, and the OR of PPD was 3.67 (95% CI 2.31 to 5.84) for them as compared to women who gave birth to a male infant. After adjusting by postnatal support from all family members, husband and parents, the ORs of PPD for women who gave birth to a female infant decreased to 2.06 (95% CI 1.20 to 3.53), 2.89 (95% CI 1.76 to 4.77) and 2.20 (95% CI 1.28 to 3.77), respectively. Discussion Increased risk of PPD in Chinese women who gave birth to a female infant can be explained to large extent by inadequate or poor postpartum support from family members, particularly husband and parents.

Folic Acid Supplementation in Pregnancy and the Risk of Pre-Eclampsia—A Cohort Study

This prospective cohort study designed to assess the effect of folic acid supplementation in pregnancy on the risk of preeclampsia (PE) took place in Ottawa, ON and Kingston, ON, Canada, from September 1, 2002 to August 31, 2008. Pregnant women, less than 20 weeks gestational age were recruited and delivered in the Ottawa region and the Kingston General Hospital. Demographic characteristics of the study participants and the patterns of supplementation of folic acid were described and occurrence of PE between women with folic acid supplementation during pregnancy and women without were compared. Multiple logistic regression was used in the estimation of the independent effect of supplementation of folic acid. Additional analyses assessing the effect of low RBC and serum folate and dose-response relationship were performed. Analyses were performed in all study participants, and then in high risk and low risk sub-groups, respectively. A total of 7,669 participants were included in the final analysis. Ninety five percent of the study participants were taking folic acid supplementation in early second trimester. The rate of PE was lower in the supplementation group than in the no supplementation group, and the difference was statistically significant in high risk women. Similar patterns of associations were observed in analysis by RBC and serum folate levels and in dose-response analysis. Folic acid supplementation in pregnancy may reduce PE risk in pregnant women, especially in those women with increased risk of developing PE.

A National Survey of Endoscopic Practice Among Gynaecologists in Canada

OBJECTIVE To assess the current status of endoscopic gynaecological surgery in Canada, as well as the attitudes, perceptions, and educational preferences regarding endoscopy among Canadian obstetrician-gynaecologists. METHODS An electronic online survey was sent to 630 obstetrician-gynaecologists in Canada through the Society of Obstetricians and Gynaecologists of Canada electronic mailing list. Survey respondents were asked about demographic variables, level of training and current practice of endoscopic procedures, reasons for and barriers to performing endoscopy, and interest in continuing surgical education in laparoscopy and hysteroscopy. RESULTS A total of 178 responses (28.3%) were collected and 152 (85.4%) analyzed. The majority of respondents were general obstetrician-gynaecologists (78.0%). More gynaecologic surgeons performed abdominal (92.7%) and vaginal hysterectomies (89.7%) than laparoscopic (68.4%) and robotic hysterectomies (2.2%). Even though 93.2% of respondents selected the endoscopic approach as the preferred approach to surgery for their patients, 38.7% of respondents did not feel that they had adequate training during residency to perform endoscopy. Lack of operating room resources and lack of time and opportunity for further training were frequently selected as major barriers to performing endoscopy. Participants identified weekend continuing medical education courses and trained endoscopic surgeon outreach as preferred methods of acquiring endoscopic skills. CONCLUSION This survey provides a contemporary assessment of the current endoscopic practice patterns of Canadian obstetrician-gynaecologists, and it helps to identify some potentially modifiable factors hindering the practice of endoscopy and some possible solutions to overcoming these barriers.

Association between labetalol use for hypertension in pregnancy and adverse infant outcomes

OBJECTIVE Labetalol and methyldopa are the two antihypertensive drugs most frequently used to control blood pressure for hypertensive disorders of pregnancy. The objective of this study was to assess if labetalol is associated with poor infant outcomes. STUDY DESIGN Retrospective population-based cohort study using the linked maternal/infant databases in the Province of Saskatchewan. Women with a diagnosis of a hypertensive disorder of pregnancy who delivered a singleton in Saskatchewan from January 1, 1990 to December 31, 2005 and who were dispensed only labetalol or only methyldopa were included in the study. Occurrences of small for gestational age (SGA)<10th percentile, SGA<3rd percentile, preterm birth, stillbirth, hospitalization for respiratory distress syndrome (RDS), sepsis, and seizure during infancy, and infant death were compared. Multiple logistic regression analysis was performed to adjust for potential confounding. RESULTS A total of 1223 eligible women were included in the final analysis. Among them, 300 received labetalol only and 923 received methyldopa only during pregnancy. For women with chronic hypertension, the rate of hospitalization for RDS, sepsis, and seizure during infancy was significantly higher for infants born to mothers who were dispensed labetalol only as compared with infants born to mothers who were dispensed methyldopa only (adjusted odds ratio (OR) 1.51, 95% confidence interval (CI) 1.02-2.22). CONCLUSION Compared with methyldopa, the use of labetalol for chronic hypertension of pregnancy may be associated with increased rate of hospitalization during infancy.

Beta-Blockers increase the risk of being born small for gestational age or of being institutionalised during infancy

To compare infant outcomes between mothers with hypertension treated by beta‐blockers alone and by methyldopa alone during pregnancy.

Trends in using beta-blockers and methyldopa for hypertensive disorders during pregnancy in a Canadian population

OBJECTIVE To describe trends in and patterns of antihypertensive drug use in a general obstetric population. STUDY DESIGN Historical cohort study. A total of 18,117 women who gave birth in a Saskatchewan hospital between January 1, 1980 and December 31, 2005 with a diagnosis of hypertensive disorders in pregnancy were identified and included in the analysis. RESULTS The rate of treatment with antihypertensive drugs for pregnant women with chronic hypertension rose from 19.94% in 1980-1984 to 37.63% in 2000-2005. There were similar increases in antihypertensive drug use from 1.51% to 14.47% for gestational hypertension/non-severe preeclampsia, and from 1.56% to 20.86% for severe preeclampsia/eclampsia. Methyldopa was the most frequently used drug, followed by beta-blockers, with other antihypertensive drugs accounting for about 18.43% of total uses. The use of both methyldopa and labetalol has increased in recent years while the use of other antihypertensive drugs has decreased. Other antihypertensive drugs were more commonly prescribed in earlier gestation, while methyldopa and labetalol were generally prescribed in later gestation. CONCLUSION The use of antihypertensive drugs in pregnancy is relatively common and is increasing, with the liberal use of methyldopa and (especially) labetalol contributing appreciably to this increase.

Cost-effectiveness of transdermal nitroglycerin use for preterm labor.

OBJECTIVE The objective of this study was to determine the cost-effectiveness of using transdermal nitroglycerin (GTN) for cases of preterm labor. METHODS The study included 153 women with clinical preterm labor, who were randomly allocated to either a GTN or placebo arm. All randomized cases were included in the final economic analysis. Differences between the two arms in gestational age at delivery, neonatal intensive care unit (NICU) admission, length of NICU stay, and NICU cost were assessed. Costs for non-NICU cases were calculated using Ottawa Hospital data through the Ontario Case Costing Initiative (OCCI). Cost-effectiveness and sensitivity analyses using a hospital perspective were both conducted. RESULTS In the 153 randomized cases, 55 babies were admitted to NICU (GTN = 24; placebo = 31). We found no significant differences between the two arms in gestational age at delivery, NICU admission rate (32.4% vs. 39.2%), NICU length of stay (42.7 days vs. 52.8 days), or NICU cost (CAN

Effect of folic acid supplementation during pregnancy on gestational hypertension/preeclampsia: A systematic review and meta-analysis

34,306 vs. CAN