Mercury exposure from dental filling placement during pregnancy and low birth weight risk.

Several European countries have guidelines suggesting that women should not receive mercury-containing dental amalgam fillings during pregnancy. One concern raised by several studies is that mercury exposure during pregnancy may lead to decreased birth weight. A population-based, case-control study was designed to investigate whether placement of mercury-containing fillings in 1993-2000 during pregnancy increased the low-birth-weight risk. Cases and controls were sampled from enrollees of a dental insurance plan with live singleton births in Washington State; 1,117 women with low-birth-weight infants (< 2,500 g) were compared with a random sample of 4,468 women with infants weighing 2,500 g or more. The results indicated that 13% of a dentally insured population had one or more restorative procedures during pregnancy that, regardless of chemical composition, did not increase the low-birth-weight risk (odds ratio = 0.96, 95% confidence interval: 0.88, 1.05). The 4.9% of the women (n = 249) who had at least one mercury-containing amalgam filling during pregnancy were not at an increased risk for a low-birth-weight infant (odds ratio = 0.75, 95% confidence interval: 0.45, 1.26) and neither were women who had 4-11 amalgam fillings placed (odds ratio = 1.00, 95% confidence interval: 0.27, 3.68). This study found no evidence that mercury-containing dental fillings placed during pregnancy increased low-birth-weight risk.

Delivery method and self-reported postpartum general health status among primiparous women.

Despite nearly four million deliveries in the United States each year, minimal information exists on unintended health consequences following childbirth, particularly in relation to delivery method. The purpose of this study was to assess the association between method of delivery and the general health status, sexual, bowel and urinary functioning of primiparous women as measured at 7 weeks postpartum. Data from the Statewide Obstetrical Review of Quality System (StORQS) Survey of Maternity Care in Washington State were analysed. Participants included all primiparous women with a delivery of a singleton infant discharged alive between August and December 1991 from 10 non-federal short-stay hospitals who responded to the StORQS Survey of Maternity Care (n = 971). The main outcome measures included the modified Medical Outcomes Study 36-Item Short-Form Health Survey and self-reported sexual, bowel and urinary functioning. At 7 weeks postpartum, women who had caesarean or assisted vaginal deliveries reported significantly lower postpartum general health status scores than women with unassisted vaginal delivery. Additionally, women with assisted vaginal delivery reported significantly worse sexual, bowel and urinary functioning. Our results suggest that more careful attention to the postpartum general health and sexual functioning of women with caesarean and assisted vaginal delivery may be merited.

Risk of uterine rupture during labor among women with a prior cesarean delivery.

BACKGROUND: Each year in the United States, approximately 60 percent of women with a prior cesarean delivery who become pregnant again attempt labor. Concern persists that a trial of labor may increase the risk of uterine rupture, an uncommon but serious obstetrical complication. METHODS: We conducted a population-based, retrospective cohort analysis using data from all primiparous women who gave birth to live singleton infants by cesarean section in civilian hospitals in Washington State from 1987 through 1996 and who delivered a second singleton child during the same period (a total of 20,095 women). We assessed the risk of uterine rupture for deliveries with spontaneous onset of labor, those with labor induced by prostaglandins, and those in which labor was induced by other means; these three groups of deliveries were compared with repeated cesarean delivery without labor. RESULTS: Uterine rupture occurred at a rate of 1.6 per 1000 among women with repeated cesarean delivery without labor (11 women), 5.2 per 1000 among women with spontaneous onset of labor (56 women), 7.7 per 1000 among women whose labor was induced without prostaglandins (15 women), and 24.5 per 1000 among women with prostaglandin-induced labor (9 women). As compared with the risk in women with repeated cesarean delivery without labor, uterine rupture was more likely among women with spontaneous onset of labor (relative risk, 3.3; 95 percent confidence interval, 1.8 to 6.0), induction of labor without prostaglandins (relative risk, 4.9; 95 percent confidence interval, 2.4 to 9.7), and induction with prostaglandins (relative risk, 15.6; 95 percent confidence interval, 8.1 to 30.0). CONCLUSIONS: For women with one prior cesarean delivery, the risk of uterine rupture is higher among those whose labor is induced than among those with repeated cesarean delivery without labor. Labor induced with a prostaglandin confers the highest risk.

First-birth cesarean and placental abruption or previa at second birth(1).

OBJECTIVE: To assess the association between first-birth cesarean delivery and second-birth placental abruption and previa. METHODS: We conducted a population-based, retrospective cohort analysis using data from the Washington State Birth Events Record Database. The study cohort included all primiparas who gave birth to live singleton infants in nonfederal short-stay hospitals from January 1, 1987, through December 31, 1996, and who had second singleton births during the same period (n = 96,975). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for placental abruption or previa at second births associated with first-birth cesareans. RESULTS: Among our study cohort, abruptio placentae complicated 11.5 per 1000 and placenta previa 5.2 per 1000 singleton deliveries at second births. In logistic regression analyses adjusted for maternal age, women with first-birth cesareans had significantly increased risk of abruptio placentae (OR 1.3, 95% CI 1.1, 1.5), and placenta previa (OR 1.4, 95% CI 1.1, 1.6) at second births, compared with women with prior vaginal deliveries. CONCLUSION: We found moderately increased risk of placental abruption and previa as a long-term effect of prior cesarean delivery on second births.

Midwives and maternal and child health: building resource capacity.

With dramatic changes in health, social services, and welfare systems and escalating pressure to increase clinical productivity, midwives need to enhance their capacity to work with federal, regional, and state partners to promote and protect comprehensive, culturally competent, and community-based quality health care for pregnant women and their families. Information about maternal and child health (MCH) regional and state resources is provided, and strategies for obtaining additional MCH resources are suggested, so that midwives and other women's health care providers can more effectively improve health care programs and systems that benefit women and their families. In addition, ways to work with MCH programs at the regional and state levels are described.

Cesarean delivery and postpartum mortality among primiparas in Washington State, 1987-1996(1).

OBJECTIVE: To examine the association between delivery method and mortality within 6 months of delivery among primiparas. METHODS: We conducted a population-based, retrospective cohort analysis using statewide, maternally linked birth certificate, hospital discharge, and death certificate data. The present cohort was all primiparas who gave birth to live-born infants in civilian hospitals in Washington State from January 1, 1987 through December 31, 1996 (n = 265,471). Odd ratios (OR) and 95% confidence intervals (CI) were calculated for overall mortality, pregnancy-related mortality, and pregnancy-unrelated mortality associated with delivery method. RESULTS: Thirty-two women (12.1 per 100,000 singleton live births) died within 6 months of delivery of their first child. Eleven of 32 deaths were pregnancy related (4.1 per 100,000 singleton live births, 95% CI 1.6, 6.5), and 21 of the 32 deaths were not pregnancy related (7.9 per 100,000 singleton live births, 95% CI 4.5, 11.3). The pregnancy-related mortality rate was higher among women delivered by cesarean (10.3/100,000) than among women delivered vaginally (2.4/100,000). In logistic regression analyses, women who had cesarean delivery were not at significantly higher risk of death overall after adjustment for maternal age (OR 1.7, 95% CI 0.3, 3.6), pregnancy-related death after adjustment for maternal age and severe preeclampsia (OR 2.2, 95% CI 0.6, 7.9), or pregnancy-unrelated death after adjustment for maternal age and marital status (OR 0.9, 95% CI 0.3, 2.7), relative to women who had vaginal delivery. CONCLUSION: Cesarean delivery might be a marker for serious preexisting morbidities associated with increased mortality risk rather than a risk factor for death in and of itself. Data from additional sources such as medical records and autopsy reports are necessary to disentangle preexisting mortality risk from risk associated solely with delivery method.

Maternal and neonatal outcomes after induction of labor without an identified indication.

OBJECTIVE: This study was undertaken to examine associations between induction of labor and maternal and neonatal outcomes among women without an identified indication for induction. STUDY DESIGN: This was a population-based cohort study of 2886 women with induced labor and 9648 women with spontaneous labor who were delivered at 37 to 41 weeks' gestation, all without identified medical and obstetric indications for induction. RESULTS: Among nulliparous women 19% of women with induced labor versus 10% of those with spontaneous labor underwent cesarean delivery (adjusted relative risk, 1.77; 95% confidence interval, 1.50-2.08). No association was seen in multiparous women (relative risk, 1.07; 95% confidence interval, 0. 81-1.39). Among all women induction was associated with modest increases in instrumental delivery (19% vs 15%; relative risk, 1.20; 95% confidence interval, 1.09-1.32) and shoulder dystocia (3.0% vs 1. 7%; relative risk, 1.32; 95% confidence interval, 1.02-1.69). CONCLUSION: Among women who lacked an identified indication for induction of labor, induction was associated with increased likelihood of cesarean delivery for nulliparous but not multiparous women and with modest increases in the risk of instrumental delivery and shoulder dystocia for all women.

Duration of treatment for asymptomatic bacteriuria during pregnancy.

BACKGROUND: A Cochrane systematic review has shown that drug treatment of asymptomatic bacteriuria in pregnant women substantially decreases the risk of pyelonephritis and reduces the risk of preterm delivery. However, it is not clear whether single dose therapy is as effective as longer conventional antibiotic treatment. OBJECTIVES: The objective of this review was to assess the effects of different durations of treatment for asymptomatic bacteriuria in pregnancy. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and the reference lists of articles. SELECTION CRITERIA: Randomised and quasi-randomised trials comparing antimicrobial therapeutic regimens that differed in duration (particularly comparing single dose with longer duration regimens) in pregnant women diagnosed with asymptomatic bacteriuria. DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted independently by the reviewers. MAIN RESULTS: Eight studies involving over 400 women were included. All were comparisons of single dose treatment with four to seven day treatments. The trials were generally of poor quality. No difference in 'no-cure' rate was detected between single dose and short course (4-7 day) treatment for asymptomatic bacteriuria in pregnant women (relative risk 1.13, 95% confidence interval 0.82 to 1.54) as well as in the recurrent asymptomtic bacteriuria (relative risk 1.08, 95% confidence interval 0.70 to 1.66). However these results showed significant heterogeneity. No differences were detected for preterm births and pyelonephritis although sample size of trials was small. Longer duration treatment was associated with an increase in reports of adverse effects (relative risk 0.53, 95% confidence interval 0.31 to 0.91). REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate whether single dose or longer duration doses are more effective in treating asymptomatic bacteriuria in pregnant women. Because single dose has lower cost and increases compliance, this comparison should be explored in a properly sized randomized controlled trial.

Association between method of delivery and maternal rehospitalization.

CONTEXT: Despite nearly 4 million deliveries in the United States each year, minimal information exists on unintended health consequences following childbirth, particularly in relation to delivery method. OBJECTIVE: To assess the risk for maternal rehospitalization associated with cesarean or assisted vaginal delivery compared with spontaneous vaginal delivery. DESIGN: Retrospective cohort study of data from the Washington State Birth Events Record Database for 1987 through November 1, 1996. SETTING AND PARTICIPANTS: All primiparous women without selected chronic medical conditions who delivered live singleton infants in nonfederal short-stay hospitals in Washington State (N =256,795). MAIN OUTCOME MEASURES: Relative risks (RRs) of rehospitalization within 60 days of cesarean or assisted vaginal vs spontaneous vaginal deliveries. RESULTS: A total of 3149 women (1.2%) were rehospitalized within 60 days of delivery. In logistic regression analyses adjusting for maternal age, rehospitalization was found to be more likely among women with cesarean delivery (RR, 1.8; 95% confidence interval [CI], 1.6-1.9) or assisted vaginal delivery (RR, 1.3; 95% CI, 1.2-1.4) than among women with spontaneous vaginal delivery. Cesarean delivery was associated with significantly increased risks of rehospitalization for uterine infection, obstetrical surgical wound complications, and cardiopulmonary and thromboembolic conditions. Among women with assisted vaginal delivery, significant increased risks were seen for rehospitalization with postpartum hemorrhage, obstetrical surgical wound complications, and pelvic injury. CONCLUSIONS: Women with cesarean and assisted vaginal deliveries were at increased risk for rehospitalization, particularly with infectious morbidities. Effective strategies for preventing and controlling peripartum infection should be an obstetrical priority.

Cesarean delivery rates in women cared for by certified nurse-midwives in the United States: a review.

The frequency of cesarean deliveries for women attended by certified nurse-midwives in the United States (1.8-10.4%) is lower than the rate for the general population of woman who gave birth in the United States in 1990 (23%). This paper describes the research that reported cesarean birth rates for certified nurse-midwives. Major methodology limitations of the research suggest that significant information gaps exist regarding nurse-midwifery care and its effect on cesarean delivery. Issues surrounding this common clinical procedure are complex, with its high cost and controversy over determinant factors. It is important to develop convincing evidence about the influence of nurse-midwives' care on reducing the frequency of cesarean delivery in the United States.

Perineal outcomes and nurse-midwifery management.

This article describes the association among perineal outcomes, selected risk factors, and alternative intrapartum approaches used by nurse-midwives. This nonrandomized concurrent (cohort) study analyzed all spontaneous vaginal births (N = 1211) attended by nurse-midwives at a university hospital over a 2-year period. Univariate analysis was used to calculate relative risks for the associations between two perineal outcomes and selected variables. Study results indicated that parity, ethnicity, birth weight, and use of two techniques (hot compresses and lubrication) were associated with lacerations. The same factors that increase the risk of perineal lacerations also made the performance of an episiotomy more likely; however, for episiotomy, an inverse relationship with perineal hot compresses was noted, and perineal lubrication had no effect. Lack of perineal support was associated with a 66% rise in the risk of episiotomy. Use of birthing positions other than lithotomy significantly reduced the likelihood of episiotomy. The authors concluded that selected care measures to protect the perineum may reduce maternal morbidity and simplify intrapartum care. The risks and benefits of alternative strategies commonly used by nurse-midwives while caring for diverse populations during birth should be further evaluated in large multiethnic populations.

Maternal age and labor complications in healthy primigravidas at term.

The objective of this study was to describe the association between maternal age and selected risk indicators (both recognized and potential) to determine whether any were predictive of labor complications in women having a first child. Low-risk primigravidas (n = 1,792) were selected from a large national probability sample of births for 1988 (the National Maternal and Infant Health Survey). Recognized and potential risk indicators were described according to categories of maternal age and the occurrence of labor problems. Stratified analysis and logistic regression were used to assess the association of various risk factors with labor complications adjusted for maternal age. Only cesarean delivery varied significantly across maternal age groups, the rate being 11.6% for those < 20, 15.9% for those age 20-29, and 28.3% for those > or = 30. Cesarean delivery was associated with several characteristics of social advantage. Independent risk factors for cesarean delivery were maternal age (particularly > or = 30), epidural anesthesia, and receipt of adequate prenatal care. We conclude that older primigravidas have significantly more cesarean deliveries, and this is partially explained by characteristics of social advantage. To address the high cesarean rate, care providers need a better understanding of the relationship between social circumstances and cesarean delivery.

Effectiveness of postpartum education received by certified nurse-midwives' clients at a university hospital.

This pilot study's objective was to determine the effectiveness of postpartum education received by midwifery clients at the University of New Mexico Hospital. The authors of the study randomized 100 women following delivery to two groups. Group one, n = 55, received written postpartum instructions only. Group two, n = 45, received oral instructions by the certified nurse-midwife in addition to the written instructions. Both groups answered a written questionnaire after the teaching. Analyses were carried out on 100 posttest scores. Mean test scores for group one was 17.9 out of a possible score of 20. Mean score for group two was 18.3. No significant difference was detected between these two mean scores. A 95% confidence interval for the difference between mean scores was -1.9 to 1.1 (P > .05). Reliability of instrument was established via the Kuder-Richardson formula 21. This conservative estimate of internal consistency yielded r = .50. The authors found that oral instructions by the certified nurse-midwife did not significantly increase the knowledge of primiparas as evidenced by posttest results. However, results must be interpreted cautiously for three reasons: low reliability of the instrument, the small difference between groups, and the sample size. The need to determine how best to approach postpartum education is imperative in this era of early hospital discharge. A certified nurse-midwife's time may be better spent focusing on individual concerns rather than on a set teaching agenda. Alternative opportunities such as postpartum home visits need to be explored as a means of providing support and guidance to new mothers.

Research trends in the Journal of Nurse-Midwifery 1987-1992.

To identify selected research trends, 69 research reports were analyzed from a sample of feature articles that were published in the Journal of Nurse-Midwifery between 1987 and 1992. Systematic appraisal was performed to classify these articles according to topic, design, sampling methodology, sample size, and funding. The largest proportion of studies were conducted on clinical topics (83%). Descriptive study designs were utilized most frequently (67%). Nonprobability sampling (81%) far exceeded probability sampling (19%); however, in 1992, probability sampling increased to 75%. With the exception of 1988, funding steadily increased over the study period. These results suggest that research has primarily focused upon clinical issues and has utilized descriptive designs and nonprobability sampling.

Accuracy of Leopold maneuvers in screening for malpresentation: a prospective study.

This study describes the accuracy of Leopold maneuvers as a screening procedure for fetal malpresentation. The frequency of fetal malpresentation ranges from 15 percent at 32 weeks to 4 percent at term. We prospectively determined fetal presentation by performing Leopold maneuvers on 150 women, followed by a fetal ultrasound examination for comparison. Experienced certified nurse-midwives performed the maneuvers with high sensitivity (88%), specificity (94%), positive predictive value (74%), and negative predictive value (97%) in a population with a 17 percent frequency of fetal malpresentation. We conclude that the maneuvers used by experienced clinicians can be effective as a screening tool for fetal malpresentation, particularly in settings where ultrasound may not be readily available.

Nurse-midwifery service model in an academic environment.

The Nurse-Midwifery Division, with the full support of the Department of Obstetrics and Gynecology, and with committed partners in the College of Nursing, is proceeding forward with a three-part mission: nurse-midwifery practice, teaching, and research. Our practice sites are likely to remain varied but stable, with half of our clients being either Hispanic or Native American. Our commitment to nurse-midwifery education is solid, and our participation in the process will continue to take several forms, including the central one of clinical preceptorships. Our research agenda will grow. We hope our experience with GRAVI-DATA will contribute to the development of a national nurse-midwifery data base. Other future goals of our research program include collaboration in multisite clinical research projects, obtaining substantial external funding and recruiting doctorally prepared investigators.