Estonian medical birth registry 1992–1994: Association of risk factors with perinatal mortality

Objective: To investigate the association of different maternal sociodemographic characteristics and infant sex with perinatal mortality among primiparas and multiparas. Study design: Analysis of routine data from the Estonian Medical Birth Registry covering the whole of Estonia. A total of 47 358 infants (including stillborns) with a birth weight 1000 g or more from 1992 through 1994 were studied. Perinatal mortality rate, crude odds ratio (OR) and adjusted OR (calculated by a logistic regression model) were used to evaluate the association. OR values were adjusted for maternal age at delivery, maternal ethnicity, educational level, residence, marital status, smoking status, history of previous abortion and infant sex. Results: The perinatal mortality rate was 12.2 per 1000 total births among primiparous and 14.3 among multiparous women. The highest adjusted ORs of perinatal deaths were found in older (35 years and over) primiparas (1.78; 95% confidence interval (CI 0.88-3.57)) and multiparas (1.81; 95% CI 1.29-2.55), in unmarried (single) primiparas (1.59; 95% CI 1.14-2.20) and multiparas (1.98; 95% CI 1.29-3.05), in smoking primiparas (1.69; 95% CI 1.09-2.63) and multiparas (1.51; 95% CI 1.02-2.25), and in multiparas with unknown smoking status (1.98; 95% CI 1.18-3.33). Conclusion: The study provides further evidence that perinatal mortality is positively associated with increased maternal age, unmarried (single) status and smoking.     

Obstetric outcomes in adolescent pregnancies: a racial/ethnic comparison

Abstract

Objective: To examine obstetric outcomes for adolescents among the major US racial/ethnic groups.

Methods: This is a retrospective cohort study of singleton births to nulliparous women aged 12 to 19 years from 1988 to 2008. The prevalence of preterm delivery, cesarean delivery, preeclampsia, gestational diabetes, low birth weight and low Apgar score were compared across African-American, Asian, Latina and White adolescents.

Results: 1865 adolescents were included in the analysis. Differences between racial/ethnic groups for rates of preterm delivery, cesarean delivery and gestational diabetes were statistically significant at p?<?0.05. African Americans had lower odds of preterm delivery (OR?=?0.58, 95% CI [0.38–0.90]) and gestational diabetes (OR?=?0.17, 95% CI [0.05–0.55]) than White adolescents. White adolescents had increased odds of cesarean delivery compared to African-American (OR?=?0.69, 95% CI [0.48–0.98]), Latina (OR?=?0.62, 95% CI [0.41–0.94]) and Asian adolescents (OR?=?0.41, 95% CI [0.25–0.68]). Although not statistically significant, White adolescents also had higher odds of low Apgar score. In the multivariate analysis, non-White adolescents continued to have improved outcomes, except in the case of low birth weight.

Conclusions: African-American, Asian and Latina adolescents may have similar or decreased risk of obstetric complications compared to White adolescents.     

Meta-analysis of the Safety of Home Birth

ABSTRACT: Background : The safety of planned home birth is controversial. This study examined the safety of planned home birth backed up by a modern hospital system compared with planned hospital birth in the Western world. Methods : A meta-analysis of six controlled observational studies was conducted, and the perinatal outcomes of 24,092 selected and primarily low-risk pregnant women were analyzed to measure mortality and morbidity, including Apgar scores, maternal lacerations, and intervention rates. Confounding was controlled through restriction, matching, or in the statistical analysis. Results : Perinatal mortality was not significantly different in the two groups (OR = 0.87, 95% CI 0.54–1.41). The principal difference in the outcome was a lower frequency of low Apgar scores (OR = 0.55; 0.41–0.74) and severe lacerations (OR = 0.61; 0.54–0.83) in the home birth group. Fewer medical interventions occurred in the home birth group: induction (statistically significant ORs in the range 0.06–0.39), augmentation (0.26–0.69), episiotomy (0.02–0.39), operative vaginal birth (0.03–0.42), and cesarean section (0.05–0.31). No maternal deaths occurred in the studies. Some differences may be partly due to bias. The findings regarding morbidity are supported by randomized clinical trials of elements of birth care relevant for home birth, however, and the finding relating to mortality is supported by large register studies comparing hospital settings of different levels of care. Conclusion : Home birth is an acceptable alternative to hospital confinement for selected pregnant women, and leads to reduced medical interventions.     

Transfers in Planned Home Births Related to Midwife Availability and Continuity: A Nationwide Population‐Based Study

ABSTRACT: Background: Planning a home birth does not necessarily mean that the birth will take place successfully at home. The object of this study was to describe reasons and risk factors for transfer to hospital during or shortly after a planned home birth. Methods: A nationwide study including all women who had given birth at home in Sweden between January 1, 1992, and July 31, 2005. A total of 735 women had given birth to 1,038 children. One questionnaire for each planned home birth was sent to the women. Of the 1,038 questionnaires, 1,025 were returned. Reasons for transfer and obstetric, socioeconomic, and care‐related risk factors for being transferred were measured using logistic regression. Results: Women were transferred in 12.5 percent of the planned home births. Transfers were more common among primiparas compared with multiparas (relative risk [RR] 2.5; 95% CI 1.8–3.5). Failure to progress and unavailability of the chosen midwife at the onset of labor were the reasons for 46 and 14 percent of transfers, respectively. For primiparas, the risk was four times greater if a midwife other than the one who carried out the prenatal checkups assisted at the birth (RR 4.4; 95% CI 2.1–9.5). A pregnancy exceeding 42 weeks increased the risk of transfer for both primiparas (RR 3.0; 95% CI 1.1–9.4) and multiparas (RR 3.4; 95% CI 1.3–9.0). Conclusions: The most common reasons for transfer to hospital during or shortly after delivery were failure to progress followed by the midwife’s unavailability at the onset of labor. Primiparas whose midwife for checkups during pregnancy was different from the one who assisted at the home birth were at increased risk of being transferred. (BIRTH 35:1 March 2008)     

Outcomes of Planned Hospital Birth Attended by Midwives Compared with Physicians in British Columbia

ABSTRACT: Background: The impact of midwifery versus physician care on perinatal outcomes in a population of women planning birth in hospital has not yet been explored. We compared maternal and newborn outcomes between women planning hospital birth attended by a midwife versus a physician in British Columbia, Canada. Methods: All women planning a hospital birth attended by a midwife during the 2‐year study period who were of sufficiently low‐risk status to meet eligibility requirements for home birth as defined by the British Columbia College of Midwives were included in the study group (n =488). The comparison group included women meeting the same eligibility requirements but planning a physician‐attended birth in hospitals where midwives also practiced (n =572). Outcomes were ascertained from the British Columbia Reproductive Care Program Perinatal Registry to which all hospitals in the province submit data. Results: Adjusted odds ratios for women planning hospital birth attended by a midwife versus a physician were significantly reduced for exposure to cesarean section (OR 0.58, 95% CI 0.39–0.86), narcotic analgesia (OR 0.26, 95% CI 0.18–0.37), electronic fetal monitoring (OR 0.22, 95% CI 0.16–0.30), amniotomy (OR 0.74, 95% CI 0.56–0.98), and episiotomy (OR 0.62, 95% CI 0.42–0.93). The odds of adverse neonatal outcomes were not different between groups, with the exception of reduced use of drugs for resuscitation at birth (OR 0.19, 95% CI 0.04–0.83) in the midwifery group. Conclusions: A shift toward greater proportions of midwife‐attended births in hospitals could result in reduced rates of obstetric interventions, with similar rates of neonatal morbidity. (BIRTH 34:2 June 2007)     

The effect of prepregnancy body mass index on birth weight,preterm birth,cesarean section,and preeclampsia in pregnant women

Objective: The objective of this study is to determine the impact of maternal prepregnancy BMI on birth weight, preterm birth, cesarean section, and preeclampsia among pregnant women delivering singleton life birth.

Methods: A cross-sectional study of 4397 women who gave singleton birth in Tehran, Iran from 6 to 21 July 2015, was conducted. Women were categorized into four groups: underweight (BMI?2), normal (BMI 18.5–25?kg/m²), overweight (BMI 25–30?kg/m²) and obese (BMI >30?kg/m²), and their obstetric and infant outcomes were analyzed using both univariate and multivariate logistic regression.

Results: Prepregnancy BMI of women classified 198 women as underweight (4.5%), 2293 normal (52.1%), 1434 overweight (32.6%), and 472 as obese (10.7%). In comparison with women of normal weight, women who were overweight or obese were at increased risk of preeclampsia (odds ratio (OR)?=?1.47, 95% CI?=?1.06–2.02; OR?=?3.67, 95% CI?=?2.57–5.24, respectively) and cesarean section (OR?=?1.21, 95% CI?=?1.04–1.41; OR?=?1.35, 95% CI?=?1.06–1.72, respectively). Infants of obese women were more likely to be macrosomic (OR?=?2.43, 95% CI?=?1.55–3.82).

Conclusion: Prepregnancy obesity is a risk factor for macrosomia, preeclampsia, and cesarean section and need for resuscitation.     

Adaptive growth restriction as a pattern of birth weight discordance in twin gestations

OBJECTIVE: To challenge the hypothesis that discordant growth is a normal variation by relating birth weight discordance to total twin birth weight. METHODS Among 12,565 Israeli live-born twin pairs (1993-98), we compared total twin birth weight decile, the frequencies of three levels of discordance in the general population, over 25% discordance between like- versus unlike-sex pairs, and over 25% discordance between pairs delivered by primiparas versus multiparas. RESULTS: We found a marked change in the best-fit correlation function with increased discordance: level 15-24.9% was inversely linear whereas levels 25-34.9% and over 34.9% were inversely logarithmic (R(2) =.47,.88, and.9, respectively). The best-fit correlation of frequencies of more than 25% discordance was inversely logarithmic and similar in like- and unlike-sexed twins across deciles functions (P =.7, odds ratio [OR] 1.0, 95% confidence interval [CI] 0.9, 1.2). The overall frequencies of discordance were also similar (9.3% versus 10.2%, P =.11, OR 0.9, 95% CI 0.8, 1.0). The frequencies of primiparas decreased linearly (R(2) =.98) and the frequencies of more than 25% discordant pairs in multiparas and primiparas across the deciles had similar inversely logarithmic patterns (P =.55, OR 1.0, 95% CI 0.9, 1.2). Discordance over 25% was significantly more frequent among primiparas (P <.001, OR 1.45, 95% CI 1.3, 1.6). CONCLUSION: The observed patterns of birth weight discordance did not substantiate normal variation but an adaptive growth restriction that might explain why the likelihood of discordant growth decreases as total twin birth weight increases.     

Impact of First Childbirth on Changes in Women’s Preference for Mode of Delivery: Follow‐up of a Longitudinal Observational Study

ABSTRACT: Background: A woman’s childbirth experience has an influence on her future preferred mode of delivery. This study aimed to identify determinants for women who changed from preferring a planned vaginal birth to an elective cesarean section after their first childbirth. Methods: This prospective longitudinal observational study involved two units that provide obstetric care in Hong Kong. A mail survey was sent to 259 women 6 months after their first childbirth. These women had participated in a longitudinal cohort study that examined their preference for elective cesarean section in the antenatal period of their first pregnancies. Univariate and multivariate analyses were performed to identify determinants for women who changed from preferring vaginal birth to elective cesarean section. Results: Twenty‐four percent (23.8%, 95% CI 18.4–29.3) of women changed from preferring vaginal birth to elective cesarean section after their first childbirth. Determinants found to be positively associated with this change included actual delivery by elective cesarean section (OR 106.3, 95% CI 14.7–767.4) intrauterine growth restriction (OR 19.5, 95% CI 1.1–353.6), actual delivery by emergency cesarean section (OR 8.4, 95% CI 3.4–20.6), higher family income (OR 3.2, 95% CI 1.1–8.8), use of epidural analgesia (OR 2.6, 95% CI 1.0–6.8), and higher trait anxiety score (OR 1.1, 95% CI 1.0–1.3). The most important reason for women who changed from preferring vaginal birth to elective cesarean section was fear of vaginal birth (24.4%). Conclusions: A significant proportion of women changed their preferred mode of delivery after their first childbirth. Apart from reducing the number of cesarean sections in nulliparous women, prompt provision of education to women who had complications and investigations into fear factors during vaginal birth might help in reducing women’s wish to change to elective cesarean section. (BIRTH 35:2 June 2008)     

Admission of Term Infants to Neonatal Intensive Care: A Population‐Based Study

ABSTRACT: Background: Neonatal intensive care and special care nurseries provide a level of care that is both high in cost and low in volume. The aim of our study was to determine the rate of admission of term babies to neonatal intensive care in association with each method of giving birth among low‐risk women. Methods: We examined the records of 1,001,249 women who gave birth in Australia during 1999 to 2002 using data from the National Perinatal Data Collection. Among low‐risk women, we calculated the adjusted odds of admission to neonatal intensive care at term separated for each week of gestational age between 37 and 41 completed weeks. We also calculated the odds of admission to neonatal intensive care in association with cesarean section before or after the onset of labor, and vacuum or instrumental birth compared with unassisted vaginal birth at 40 weeks’ gestation. Results: The overall rate of admission to neonatal intensive care of term babies was 8.9 percent for primiparas and 6.3 percent for multiparas. After a cesarean section before the onset of labor, the adjusted odds of admission among low‐risk primiparas at 37 weeks’ gestation were 12.08 (99% CI 8.64–16.89); at 38 weeks, 7.49 (99% CI 5.54–10.11); and at 39 weeks, 2.80 (99% CI 2.02–3.88). At 41 weeks, the adjusted odds were not significantly higher than those at 40 weeks’ gestation. Among low‐risk multiparas who had a cesarean section before the onset of labor, the adjusted odds of admission to neonatal intensive care at 37 weeks’ gestation were 15.40 (99% CI 12.87–18.43); at 38 weeks, 12.13 (99% CI 10.37–14.19); and at 39 weeks, 5.09 (99% CI 4.31–6.00). At 41 weeks’ gestation, the adjusted odds of admission were significantly lower than those at 40 weeks (AOR 0.64, 99% CI 0.47–0.88). Babies born after any operative method of birth were at increased odds of being admitted to neonatal intensive care compared with those born after unassisted vaginal birth at 40 weeks’ gestation. Conclusions: The adjusted odds of admission to neonatal intensive care for babies of low‐risk women were increased after birth at 37 weeks’ gestation. In a climate of rising cesarean sections, this information is important to women who may be considering elective procedures. (BIRTH 34:4 December 2007)     

Induction of labor after one prior cesarean: predictors of vaginal delivery

OBJECTIVE: To estimate the characteristics most associated with vaginal birth in patients undergoing induction of labor after 1 prior cesarean delivery. METHODS: All patients who presented for induction of labor from 1996 to 2001 with a history of 1 prior cesarean delivery were identified. Relevant demographic and obstetric data were abstracted from the charts. Univariate analysis was used to identify predictive factors associated with vaginal birth after cesarean. Binary logistic regression was further used to identify which factors were independently associated with the outcome measure. RESULTS: Of the 429 women included in the study, 334 (77.9%) had a successful trial of labor. In the final binary logistic regression equation, prior vaginal delivery (odds ratio [OR] 3.75; 95% confidence interval [CI] 1.96, 7.18) remained independently associated with an increased chance of a vaginal delivery after a trial of labor. Conversely, prior cesarean delivery for dystocia (OR 0.46; 95% CI 0.27, 0.79), induction on or past the estimated date of delivery (OR 0.46; 95% CI 0.27, 0.78), need for cervical ripening (OR 0.35; 95% CI 0.20, 0.61), and maternal gestational or preexisting diabetes (OR 0.16; 95% CI 0.06, 0.40) were all factors associated with a decreased likelihood of achieving a successful trial of labor. CONCLUSION: Several factors are available which may assist in identifying patients with the best chance of vaginal delivery after an induction of labor in the presence of a prior low-transverse cesarean scar. LEVEL OF EVIDENCE: II-2     

Childhood Abuse and Fear of Childbirth—A Population‐based Study

Abstract: Background: Childhood abuse affects adult health. The objective of this study was to examine the association between a self‐reported history of childhood abuse and fear of childbirth. Methods: A population‐based, cross‐sectional study was conducted of 2,365 pregnant women at five obstetrical departments in Norway. We measured childhood abuse using the Norvold Abuse Questionnaire and fear of childbirth using the Wijma Delivery Expectancy Questionnaire. Severe fear of childbirth was defined as a Wijma Delivery Expectancy Questionnaire score of ≥85. Results: Of all women, 566 (23.9%) had experienced any childhood abuse, 257 (10.9%) had experienced emotional abuse, 260 (11%) physical abuse, and 290 (12.3%) sexual abuse. Women with a history of childhood abuse reported severe fear of childbirth significantly more often than those without a history of childhood abuse, 18 percent versus 10 percent (p = 0.001). The association between a history of childhood abuse and severe fear of childbirth remained significant after adjustment for confounding factors for primiparas (adjusted OR: 2.00; 95% CI: 1.30–3.08) but lost its significance for multiparas (adjusted OR: 1.17; 95% CI: 0.76–1.80). The factor with the strongest association with severe fear of childbirth among multiparas was a negative birth experience (adjusted OR: 5.50; 95% CI: 3.77–8.01). Conclusions: A history of childhood abuse significantly increased the risk of experiencing severe fear of childbirth among primiparas. Fear of childbirth among multiparas was most strongly associated with a negative birth experience. (BIRTH 37:4 December 2010)     

Effect of fear of litigation on obstetric care: a nationwide analysis on obstetric practice

The aim of our study was to investigate the influence of malpractice premiums paid by obstetricians on obstetric care across the United States. We conducted a retrospective cross-sectional population-based study using patient-level data obtained from the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample on every woman who delivered in 2006. Mode of delivery was compared with the average state medical liability insurance premium paid by obstetricians (Medical Liability Monitor and the National Association of Insurance Commissioners) using a generalized estimating equation to calculate crude and adjusted odds ratios. Our cohort included 890,266 women who delivered across 37 states in 2006. Average state malpractice premium of over $100,000 was associated with higher incidences of total cesarean deliveries (odds ratio [OR] 1.17, 95% confidence interval [CI]: 1.02, 1.35); lower incidences of vaginal births after cesarean deliveries (OR 0.60, 95% CI: 0.37, 0.98); and lower rates of instrumental deliveries (OR 0.72, 95% CI: 0.63, 0.83) compared with when the average state malpractice premium was less than $50,000. Fear of litigation appears to have a marked effect on obstetric practice, particularly total cesarean delivery, vaginal birth after cesarean, and instrumental delivery, when malpractice premiums rise above $100,000 per annum.     

New postnatal urinary incontinence: obstetric and other risk factors in primiparae

OBJECTIVE: To identify obstetric and other risk factors for urinary incontinence that occurs during pregnancy or after childbirth. DESIGN: Questionnaire survey of women. SETTING: Maternity units in Aberdeen (Scotland), Birmingham (England) and Dunedin (New Zealand). POPULATION: A total of 3405 primiparous women with singleton births delivered during 1 year. METHODS: Questionnaire responses and obstetric case note data were analysed using multivariate analysis to identify associations with urinary incontinence. MAIN OUTCOME MEASURES: Urinary incontinence at 3 months after delivery first starting in pregnancy or after birth. RESULTS: The prevalence of urinary incontinence was 29%. New incontinence first beginning after delivery was associated with older maternal age (oldest versus youngest group, OR 2.02, 95% CI 1.35-3.02) and method of delivery (caesarean section versus spontaneous vaginal delivery, OR 0.28, 95% CI 0.19-0.41). There were no significant associations with forceps delivery (OR 1.18, 95% CI 0.92-1.51) or vacuum delivery (OR 1.16, 95% CI 0.83-1.63). Incontinence first occurring during pregnancy and still present at 3 months was associated with higher maternal body mass index (BMI>25, OR 1.68, 95% CI 1.16-2.43) and heavier babies (birthweight in top quartile, OR 1.56, 95% CI 1.12-2.19). In these women, caesarean section was associated with less incontinence (OR 0.39, 95% CI 0.27-0.58) but incontinence was not associated with age. CONCLUSIONS: Women have less urinary incontinence after a first delivery by caesarean section whether or not that first starts during pregnancy. Older maternal age was associated with new postnatal incontinence, and higher BMI and heavier babies with incontinence first starting during pregnancy. The effect of further deliveries may modify these findings.     

Risk of cesarean delivery with elective induction of labor at term in nulliparous women.

OBJECTIVE: To quantify the risk of cesarean delivery associated with elective induction of labor in nulliparous women at term. METHODS: We performed a cohort study on a major urban obstetric service that serves predominantly private obstetric practices. All term, nulliparous women with vertex, singleton gestations who labored during an 8-month period (n = 1561) were divided into three groups: spontaneous labor, elective induction, and medical induction. The risk of cesarean delivery in the induction groups was determined using stepwise logistic regression to control for potential confounding factors. RESULTS: Women experiencing spontaneous labor had a 7.8% cesarean delivery rate, whereas women undergoing elective labor induction had a 17.5% cesarean delivery rate (adjusted odds ratio [OR] 1.89; 95% confidence interval [CI] 1.12, 3.18) and women undergoing medically indicated labor induction had a 17.7% cesarean delivery rate (OR 1.69; 95% CI 1.13, 2.54). Other variables that remained significant risk factors for cesarean delivery in the model included: epidural placement at less than 4 cm dilatation (OR 4.66; 95% CI 2.25, 9.66), epidural placement after 4 cm dilatation (OR 2.18; 95% CI 1.06, 4.48), chorioamnionitis (OR 4.61; 95% CI 2.89, 7.35), birth weight greater than 4000 g (OR 2.59; 95% CI 1.69, 3.97), maternal body mass index greater than 26 kg/m2 (OR 2.36; 95% CI 1.61, 3.47), Asian race (OR 2.35; 95% CI 1.04, 5.34), and magnesium sulfate use (OR 2.18; 95% CI 1.04, 4.55). CONCLUSION: Elective induction of labor is associated with a significantly increased risk of cesarean delivery in nulliparous women. Avoiding labor induction in settings of unproved benefit may aid efforts to reduce the primary cesarean delivery rate.     

Safety of birth centre care: perinatal mortality over a 10-year period

Objective   To study perinatal mortality in women booked for birth centre care during pregnancy.
Design   Retrospective cohort study.
Setting   In-hospital birth centre and standard maternity care in Stockholm.
Population   Two thousand and five hundred and thirty-four women (3256 pregnancies) admitted to an in-hospital birth centre over 10 years (1989–2000) and 126,818 women (180,380 pregnancies) who gave birth in standard care during the same period and who met the same medical inclusion criteria as in the birth centre. Multiple pregnancies were excluded.
Methods   Data were collected from the Swedish Medical Birth Register. Information on all cases of perinatal death in the birth centre group was retrieved from the medical records.
Main outcome measure   Perinatal mortality.
Results   No statistically significant difference in the overall perinatal mortality rate was observed between the birth centre group and the standard care group (odds ratio [OR] 1.5, 95% CI 0.9–2.4), but infants of primiparas were at greater risk (OR 2.2, 95% CI 1.3–3.9). Infants of multiparas tended to be at lower risk, but this difference was not statistically significant (OR 0.7, 95% CI 0.3–1.9). These figures were adjusted for maternal age and gestation in multiple regression analyses.
Conclusion   Birth centre care may be less safe for infants of first-time mothers.     

Continuity of Nursing Care and Its Link to Cesarean Birth Rate

ABSTRACT: Background: High cesarean birth rates are an international concern. The role of patterns of nursing care responsibility in preventing or contributing to cesarean births has been understudied. Our study sought to identify and describe indicators of continuity of nursing care responsibility during labor and to explore whether any association between these indicators and risk of cesarean birth could be identified empirically using an existing data set. Methods: We obtained a representative sample of low‐risk women giving birth in an intrapartum unit at a university hospital in Quebec, Canada, with approximately 3,700 births per year. To be considered for inclusion, women needed to have been primiparous, carrying singletons in vertex position, and at 37 weeks’ gestation or more. All women giving birth over a 13‐month period were assessed for eligibility using the hospital’s birth log. Data were extracted from the medical records of every second eligible birth, including information related to patterns of nursing care responsibility, maternal and infant characteristics, obstetric procedures, non–health‐related risk factors, and type of birth. Results: Data on all variables of interest were available for 467 women. These women were cared for by 1–17 nurses, care responsibility changed hands for them from 1 to 28 times, and the mean length of labor for which the same nurse was responsible for a woman ranged from 10 to 1,045 minutes. After controlling for length of labor, maternal age, maternal height, infant weight, gestational age, induction, type of rupture, and epidural analgesia, the odds ratio for cesarean birth due to number of nurses was 1.17 (95% CI 1.04, 1.32); 1 or more nurses switch per 2 hours (i.e., number of times care responsibilities changed hands), 1.04 (95% CI 0.62, 1.74); and 33 percent or more of the labor attended by the same nurse, 0.74 (95% CI 0.42, 1.30). Conclusions: An association was observed between number of nurses caring for a laboring woman and risk of cesarean delivery. Estimates of the association of other patterns of nursing care responsibility on cesarean birth were not sufficiently precise to draw conclusions. (BIRTH 34:1 March 2007)     

Prolonged labour attributed to large fetus

The aim of this study is to assess the interactive dynamics of power, passenger and passage in relation to an adverse course of labour. The design was a community-based follow-up of all women with singleton pregnancies experiencing spontaneous term labour. Median of first stage was 2.6 h for multiparas and 3.7 h for primiparas. Median of second stage was 20 min for multiparas and 91 min for primiparas. Heavy birth weight significantly influenced a prolonged late first stage OR 6.6 (CI 2.1-21) and second stage of labour OR 4. 5 (CI 1.5-14) among primiparas. The attributable proportions of heavy birth weight for prolonged labour were 19-21%. Large paediatric head circumference showed a positive correlation to prolonged late first stage OR 3.2 (CI 1.2-9) and intervention OR 7.2 (CI 1.8-35), with an attributable proportion of 22%. For multiparas no significant association were found. To conclude, this study indicates that heavy birth weight and large head circumference contribute to 1/5th of the prolongation of labour and interventions among primiparas.     

The Effect of Maternal Age on Adverse Birth Outcomes: Does Parity Matter?

ObjectivesTo examine the effect of parity on the association between older maternal age and adverse birth outcomes, specifically stillbirth, neonatal death, preterm birth, small for gestational age, and neonatal intensive care unit admission.MethodsWe conducted a retrospective cohort study of singleton births in British Columbia between 1999 and 2004. In the cohort, 69 023 women were aged 20 to 29, 25 058 were aged 35 to 39, and 4816 were aged 40 and over. Perinatal risk factors, obstetric history, and birth outcomes were abstracted from the British Columbia Perinatal Database Registry. Logistic regression was used to calculate adjusted odds ratios (aOR) and 95% confidence intervals for adverse outcomes in the two older age groups compared with the young control subjects.ResultsCompared with younger control subjects, women aged 35 to 39 years had an aOR of stillbirth of 1.5 (95% CI 1.2 to 1.9) and women aged ≥ 40 years also had an aOR of 1.5 (95% CI 1.0 to 2.4). The aOR for NICU admission was 1.2 (95% CI 1.0 to 1.3) in women aged 35 to 39 years and 1.4 (95% CI 1.1 to 17) in women aged ≥ 40 years compared with younger control subjects. The risk of preterm birth and SGA differed by parity. The aOR for preterm birth compared with younger primiparas was 1.5 (95% CI 1.4 to 1.7) for women aged 35 to 39 years and 1.6 (95% CI 1.3 to 2.0) for women aged ≥ 40 years. In multiparas the aOR for preterm birth was 1.1 (95% CI 1.1 to 1.2) in women aged 35 to 39 and 1.3 (95% CI 1.1 to 1.5) in women > 40 years. The aOR for SGA in primiparas was 1.2 (95% CI 1.1 to 1.4) for women aged 35 to 39 and 1.4 (95% CI 1.1 to 1.7) for women aged ≥ 40 years. The risk of neonatal death was not significantly different between groups.ConclusionOlder women were at elevated risk of stillbirth, preterm birth, and NICU admission regardless of parity. Parity modified the effect of maternal age on preterm birth and SGA. Older primiparas were at elevated risk for SGA, but no association between age and SGA was found in multiparas. Older primiparas were at higher risk of preterm birth than older multiparas compared with younger women.