Childbearing beyond age 40: pregnancy outcome in 24,032 cases

Objective: To examine pregnancy outcomes in women age 40 or older.Methods: We used data from the California Health Information for Policy Project, which consists of linked records from the birth certificate and the hospital discharge record of both mother and newborn of all births that occurred in acute care civilian hospitals in California between January 1, 1992, and December 31, 1993. The study population consisted of all women who delivered at age 40 or over. The control population was women who delivered between age 20 and 29 years during this 2-year period. We reviewed gestational age at delivery, birth weight, mode and type of delivery, discharge summary and birth certificate demographics, birth outcome, pregnancy, and delivery data.Results: Approximately 1,160,000 women delivered during the study period, and 24,032 (2%) of these women were age 40 or older. Of this latter group, 4777 (20%) were nulliparous. The cesarean delivery rate for nulliparous women in the study population was 47.0%, and the rate for multiparous patients in this group was 29.6%. The cesarean delivery rate was 22.5% for nulliparous and 17.8% for multiparous women in the control group. In the older group, the operative vaginal delivery rate (forceps and vacuum) was 14.2% for nulliparous women and 6.3% for multiparous women. Rates of birth asphyxia, fetal growth restriction, malpresentation, and gestational diabetes were significantly higher among older nulliparas (6, 2.5, 11, and 7%, respectively) compared with rates among control nulliparas (4, 1.4, 6, and 1.7%, respectively), and there were similar significant increases among older multiparas (3.4, 1.4, 6.9, and 7.8%, respectively), compared with younger multiparous controls (2.4, 1, 3.7, and 1.6%, respectively). Mean (± standard error) birth weight of infants delivered by older nulliparous women was 3201 ± 10 g, significantly lower than that among nulliparous controls (3317 ± 1 g), whereas mean birth weight in the group of older multiparas (3381 ± 5 g) was no different than that among younger multiparous controls (3387 ± 1 g). Gestational age at delivery was significantly lower among older nulliparas (273.4 ± 0.4 days), compared with nulliparous controls (278.5 ± 0.05 days), and similarly lower among older multiparous women (274.0 ± 0.2 days), compared with multiparous controls (278.3 ± 0.05 days). More white women age 40 or over than younger white women were having a first child (64 and 39%, respectively).Conclusion: Nulliparous women age 40 or over have a higher risk of operative delivery (cesarean, forceps, and vacuum deliveries: 61%) than do younger nulliparous women (35%). This increase occurs in spite of lower birth weight and gestational age and may be explained largely by the increase in other complications of pregnancy. The increased frequency at which white women are having their first child at age 40 or over may reflect career choices that involve delaying childbirth until the fifth decade of life. These data will allow us better to counsel patients about their pregnancy expectations and possible outcomes.     

Maternal complications of pregnancy increase beyond 40 weeks of gestation in low-risk women.

OBJECTIVE: We sought to determine when rates of maternal pregnancy complications increase for low-risk nulliparous and multiparous women at term. METHODS: We designed a retrospective cohort study of low-risk women delivered beyond 37 weeks gestational age from 1976 to 2001. Rates of mode of delivery and maternal complications of labor and delivery were examined by gestational age with both bivariate and multivariate analyses. Statistical significance was designated by P<0.05. RESULTS: We found that among the 32,828 low-risk women who delivered at 37 completed weeks and beyond, the rates of primary cesarean delivery, operative vaginal delivery, third- or fourth-degree perineal lacerations, and chorioamnionitis all increased at 40 weeks of gestation (P<0.001), and the rate of postpartum hemorrhage increased at 41 weeks of gestation (P<0.001). These increases of rates of complications were larger and increased at an earlier gestational age among nulliparous women. CONCLUSION: We found that the risk of maternal complications for otherwise low risk nulliparous and multiparous women increased as pregnancy progressed beyond 40 weeks of gestation. Counseling of women who progress past their EDC should include comparing the risks of induction of labor to that of expectant management.     

Term induction of labor and risk of cesarean delivery by parity

Abstract

Objective: To evaluate the risk of cesarean delivery among both nulliparous and multiparous women undergoing a term induction of labor compared to women that present in spontaneous labor at term.

Methods: We performed a retrospective cohort study of term (≥37 weeks) singleton pregnancies between 2005 and 2010 comparing women that had an induction to those that presented in spontaneous labor. Multiparity was defined as a prior delivery after 20 weeks’ gestation. Chi-square was used to compare categorical variables. Multivariable logistic regression was used to control for confounders. Analyses were stratified by parity.

Results: 863 women were included in the analysis. There were 605 inductions (cesarean rate 23%) and 257 spontaneous labor (cesarean rate 7%), OR 3.4, 95% CI [2.1–5.4]. Stratified by parity, nulliparas undergoing induction had an increased cesarean rate compared to spontaneous labor (27% versus 11%, OR 3.13, 95% CI [1.76–5.57]) as did multiparas (13% versus 3%, OR 4.04, 95% CI [1.36–11.94]). This increased risk for cesarean after induction remained in both nulliparous and multiparous women even after controlling for confounders (aOR 2.90, 95% CI [1.60–5.25] and aOR 3.47, 95% CI [1.12–10.67], respectively). Neither starting cervical exam nor indication for induction altered this increased risk.

Conclusions: The increased risk of cesarean in women undergoing an induction is present regardless of parity and indication for induction. This should be taken into account when counseling women regarding risks of induction, regardless of parity. Future studies should focus on other clinical characteristics of induction that may mitigate this risk.     

Impact of advanced maternal age on pregnancy outcome

The aim of this study was to compare the pregnancy outcome and delivery complications in women 40 years or older (cases) to that of women 20 to 30 years old (controls). Over a 5-year period, 319 cases had a singleton delivery in our institution. These women were compared with 326 controls. Parity was significantly higher in cases compared with controls (3.2 vs. 1.8). Advanced maternal age, compared with younger age, was associated with significantly higher rates of preterm delivery (16.0 vs. 8.0%), cesarean delivery (CS) (31.3 vs. 13.5%), and the occurrence of one or more antepartum complications (29.5 vs. 16.6%). When the two groups were subdivided according to parity, rates of preterm delivery, CS, preeclampsia, gestational diabetes, chronic hypertension, and labor induction were each significantly higher among older multiparas compared with control multiparas. However, only preterm delivery, CS rates, and uterine fibroids were found to be significantly higher in older nulliparous compared with young nulliparous women. We conclude that multiparous women at least 40 years old have a higher antepartum complication rate including intrauterine fetal death compared with younger women.     

Effect of parity and advanced maternal age on obstetric outcome.

OBJECTIVES: To examine the effect of parity on obstetric outcome in women aged 40 years or older. METHODS: A retrospective cohort of 16 427 singleton pregnancies delivered between 1998 and 2001 was studied. Obstetric outcomes in women aged 40 years or older versus women younger than 40 years were compared for both nulliparous and multiparous women. RESULTS: Of the 15 727 pregnancies (95.7%) that satisfied the inclusion criteria, 606 (3.9%) were in women aged 40 years or older. Advanced age was independently associated with cesarean delivery, birth and spontaneous preterm labor before 37 weeks, and low birth weight neonates in nulliparous women, but only with preterm birth before 37 weeks and cesarean delivery in multiparous women. CONCLUSION: Obstetric outcome in women aged 40 years or older was influenced by parity. Cesarean delivery and preterm birth before 37 weeks were independently associated with older age irrespective of parity. Advanced age is a risk factor for preterm birth.     

Demographic and obstetric factors influencing pregnancy outcome in twin gestations

OBJECTIVE: Our purpose was to identify the influence of parity and previous preterm delivery on pregnancy outcome in twin gestations. STUDY DESIGN: A retrospective comparative analysis of women with twin gestations completing an outpatient preterm labor surveillance program between April 1995 and February 2000 was performed. Included were those enrolled at <24 weeks' gestation. Parity, maternal age, prepregnancy body mass index (BMI), cerclage, tocolytic use, and pregnancy outcome were identified. Data were divided into nulliparas, multiparas without previous preterm delivery, and those with previous preterm delivery. Analysis of variance and the Pearson chi2 test were used for statistical analysis. RESULTS: Data were analyzed for 1268 twin pregnancies. The mean gestational age at delivery for the multiparous women without a history of previous preterm delivery (35.3 +/- 2.7 weeks) was significantly greater than the mean gestational age at delivery for nulliparous (34.4 +/- 3.2 weeks) and multiparous women with a previous preterm delivery (34.0 +/- 3.1 weeks), P <.001. The greater gestational age at delivery in the multiparous women without a previous preterm delivery was associated with a significantly shorter newborn hospital stay and a lower need for mechanical ventilation use compared with the other groups (all P values < or =.001). CONCLUSION: In twin gestations, multiparous women without history of previous preterm delivery have a significantly greater gestational age at delivery, a lower incidence of cerclage, and a reduced neonatal hospital stay than do nulliparous women or those with a history of a previous preterm delivery.     

Pregnancy outcome at age 40 and older

Objective: Our purpose was to examine pregnancy outcomes among women age 40 or older. Methods: Between January, 1997 and December 1999, we performed a case-control study compared pregnancy outcomes of 468 patients delivered at our hospital at > Or = 40 years old with outcomes in a control group consisting of the next two deliveries of women with ages 20 to 29 years. Retrospective analysis of the antepartum and intrapartum records was done to compare clinical outcome. Results: Approximately 25,356 women delivered during the study period, and 468 (1.8%). Of these women were at age 40 or older. Of this latter group, 50 (10.7%) were nulliparous. Mean birthweight of infants delivered by older nulliparous women was significantly lower than that among nulliparous controls (3210 ± 5 vs. 3320 ± 1 g), whereas mean birth weight in the group of older multiparous was not different than that among younger multiparous controls (3370 ± 1 vs. 3365 ± 4 g). Gestational age at delivery was significantly lower among older nulliparous, and multiparous compared with nulliparous and multiparous younger controls. Older women were at increased risk for cesarean delivery (nulliparous 18%; multiparous 14%) compared with nulliparous and multiparous younger control groups (nulliparous 8%; multiparous 6%). In the study group, the operative vaginal delivery rate was higher than that of the control group. The study groups were more likely to develop gestational diabetes, preeclampsia, and placenta praevia. Older nulliparous had an increased incidence of malpresentation, abnormal labour patterns, special care baby unit admission (SCBU), and low 1-minute Apgar score. Older multiparous were more likely to experience birth asphyxia, premature rupture of membranes, and antepartum vaginal bleeding. Conclusion: Nulliparous women age 40 or over have a higher risk of operative delivery than do youngr nulliparous women. This increase occurs in spite of lower birth weight and gestational age and may be explained by the increase incidence of obstetric complications. Although maternal morbidity was increased in the older women, the overall neonatal outcome did not appear to be affected. Received: 10 May 2000 / Accepted: 26 July 2000     

Increased risk of cesarean delivery with advancing maternal age: indications and associated factors in nulliparous women

OBJECTIVE: To investigate factors that contribute to the increased risk of cesarean delivery with advancing maternal age. STUDY DESIGN: We reviewed demographic and ante- and intrapartum variables from a data set of term, nulliparous women who delivered at Brigham and Women's Hospital in 1998 (n = 3715). RESULTS: Cesarean delivery rates increased with advancing maternal age (< 25 years, 11.6%; > or = 40 years, 43.1%). Older women were more likely to have cesarean delivery without labor (< 25 years, 3.6%; > or = 40 years, 21.1%). Malpresentation and prior myomectomy were the indications for cesarean delivery without labor that were more prevalent in our older population as compared to our younger population. Even among women with spontaneous or induced labor, cesarean delivery rates increased with maternal age (< 25 years, 8.3%; > or = 40 years, 30.6%). Cesarean delivery rates were higher with induced labor, and rates of induction rose directly and continuously with maternal age, especially the rate of elective induction. Cesarean delivery for failure to progress or fetal distress was more common among older parturients, regardless of whether labor was spontaneous or induced. Among women who underwent cesarean delivery because of failure to progress, use of oxytocin and length of labor did not vary with age. CONCLUSIONS: Older women are at higher risk for cesarean delivery in part because they are more likely to have cesarean delivery without labor. However, even among those women who labor, older women are more likely to undergo cesarean delivery, regardless of whether labor is spontaneous or induced. Part of the higher rate among older women who labor is explained by a higher rate of induction, particularly elective induction. Among women in both spontaneous and induced labor, cesarean delivery for the diagnoses of failure to progress and fetal distress was more frequent in older patients, although management of labor dystocia for these patients was similar to that for younger patients.     

The association of maternal weight with cesarean risk, labor duration, and cervical dilation rate during labor induction

OBJECTIVE: To assess the relationship among maternal weight and cesarean delivery, cervical dilation rate, and labor duration. METHODS: We used a secondary analysis of 509 term women who were previously enrolled in a prospective observational study of a labor induction protocol in which standardized criteria were used for labor management. A variety of analyses were performed, both unadjusted and adjusted. P <.05 was considered significant. RESULTS: The mean +/- standard deviation weight of women who underwent a cesarean (97 +/- 29 kg) was significantly higher than that of women who were delivered vaginally (87 +/- 22 kg, P <.001). In a logistic regression model of nulliparas who comprised 71% of the study population, after adjustment for the confounding effects of infant birth weight, maternal age, initial cervical dilation, and diabetes, for each 10-kg increase in maternal weight, the odds ratio for cesarean delivery was significantly increased (odds ratio 1.17; 95% confidence interval 1.04, 1.28). In a linear regression model also limited to nulliparas and after adjusting for the same confounders, the rate of cervical dilation was inversely associated with maternal weight: for each 10-kg increment, the rate of dilation was decreased by 0.04 cm/h (P =.05). Similarly, labor duration was positively associated with maternal weight: for each 10-kg increment, an increase in the oxytocin to delivery interval of 0.3 hours was observed in nulliparas (P =.02). Neither lower rates of oxytocin administration to heavier women nor diminished uterine responsiveness (as reflected in measured Montevideo units) accounted for the slower labor progress. CONCLUSION: In nulliparous women undergoing labor induction, maternal weight was associated with a higher cesarean risk and longer labor and was inversely proportional to the cervical dilation rate. LEVEL OF EVIDENCE: II-2     

Physicians who induce labor for fetal macrosomia do not reduce cesarean delivery rates.

OBJECTIVE: To determine whether obstetricians with high rates of induction for the indication of fetal macrosomia had higher or lower cesarean section rates. STUDY DESIGN: Data were analyzed from 1432 deliveries with birthweights > 4000 g. Four physician populations were identified: a faculty service and three groups of private practitioners with induction rates 20% to 40%, 40% to 60% and > 60%. The average cesarean section rate was determined for each group as well as the percentage of each group's deliveries occurring before 39 weeks, at 39, at 40, and after 40 weeks. In addition, the relative risk of cesarean delivery was calculated for the entire study population. RESULTS: No correlation was found between the rate of induction of labor and the rate of cesarean section. Delivery of nulliparous and multiparous patients after 40 weeks carried an increased risk of cesarean section. Delivery of multiparous patients before 39 weeks did also. Obstetricians with induction rates > 40% significantly decreased the incidence of delivery after 40 weeks, which lowered their cesarean section rates, but no net lowering occurred because of increased rate of cesarean section < 39 weeks. CONCLUSION: A fetal weight of 4000 g or more is not an indication for induction of labor. For multiparous patients, induction at 38 weeks or before is associated with an increased rate of cesarean delivery.     

Elective induction of labor in multiparous women. Does it increase the risk of cesarean section?

OBJECTIVE: To determine whether the medical initiation of labor places the multiparous woman at increased risk of cesarean section. STUDY DESIGN: This study was a retrospective, case-control assessment of the risk of cesarean section in multiparas with no medical or obstetric complications and vertex presentations whose induction of labor at term was judged to be elective by chart analysis. Case women were matched for age, parity, gestational age and staff obstetrician with controls in spontaneous labor, and the rates of cesarean delivery were compared. RESULTS: Three hundred four case-control pairs were studied. No significant difference was observed in the rate of cesarean delivery between the two groups. The rate of cesarean section in the electively induced group was 3.6% versus 4.3% in the control group (P = .6670). Neither cervical state nor use of cervical ripening agents significantly affected the rate of cesarean delivery. CONCLUSION: As compared with spontaneous labor, the elective induction of labor in multiparous women without complications does not predispose to cesarean delivery.     

The influence of maternal age on pregnancy outcome in nulliparous women with twin gestation

We sought to determine if outcomes of nulliparous twin pregnancies differ based on maternal age. Nulliparous women with current twin pregnancies were identified from a database of women enrolled for outpatient nursing surveillance. Data were stratified into four groups by maternal age: less than 20, 20 to 34, 35 to 39, and greater than or equal to 40 years. Maternal and neonatal outcomes for women less than 20, 35 to 39, and 40 or more were compared with 20- to 34-year-old controls using Kruskal-Wallis, Mann-Whitney, and Pearson chi-square analyses. We analyzed 2144 nulliparous twin pregnancies. Patients ≥35 years (34 to 39, 78.5% or ≥40, 85.9%) were more likely to have cesarean deliveries compared with controls 20 to 34 years old (71.2%). Women aged 35 to 39 were less likely to deliver at <37 weeks, and women in the ≥40 group were less likely to deliver at <35 weeks due to spontaneous preterm labor compared with the controls. Neonates born to women aged 35 to 39 had a greater gestational age at delivery and larger average birth weight than controls. Maternal and neonatal outcomes were not adversely influenced by advanced maternal age in nulliparous women carrying twin gestations.     

Bishop score and risk of cesarean delivery after induction of labor in nulliparous women

OBJECTIVE: To quantify the risk and risk factors for cesarean delivery associated with medical and elective induction of labor in nulliparous women. METHODS: A prospective cohort study was performed in nulliparous women at term with vertex singleton gestations who had labor induced at 2 obstetrical centers. Medical and elective indications and Bishop scores were recorded before labor induction. Obstetric and neonatal data were analyzed and compared with the results in women with a spontaneous onset of labor. Data were analyzed using univariate and multivariable regression modeling. RESULTS: A total of 1,389 women were included in the study. The cesarean delivery rate was 12.0% in women with a spontaneous onset of labor (n = 765), 23.4% in women undergoing labor induction for medical reasons (n = 435) (unadjusted odds ratio [OR] 2.24; 95% confidence interval [CI] 1.64-3.06), and 23.8% in women whose labor was electively induced (n = 189) (unadjusted OR 2.29; 95% CI 1.53-3.41). However, after adjusting for the Bishop score at admission, no significant differences in cesarean delivery rates were found among the 3 groups. A Bishop score of 5 or less was a predominant risk factor for a cesarean delivery in all 3 groups (adjusted OR 2.32; 95% CI 1.66-3.25). Other variables with significantly increased risk for cesarean delivery included maternal age of 30 years or older, body mass index of 31 or higher, use of epidural analgesia during the first stage of labor, and birth weight of 3,500 g or higher. In both induction groups, more newborns required neonatal care, more mothers needed a blood transfusion, and the maternal hospital stay was longer. CONCLUSION: Compared with spontaneous onset of labor, medical and elective induction of labor in nulliparous women at term with a single fetus in cephalic presentation is associated with an increased risk of cesarean delivery, predominantly related to an unfavorable Bishop score at admission. LEVEL OF EVIDENCE: II-2.     

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.     

Induction of labor in elderly nulliparous women

Purpose: Maternal age is an important consideration for antenatal care, labor and delivery. We aimed to evaluate the induction of labor (IoL) failure rates among elderly nulliparous women.

Materials and methods: We conducted a retrospective analysis of all nulliparous women at 34?+?0 to 41?+?6 weeks, undergoing cervical ripening by prostaglandin E2 (PGE2) vaginal insert. Study group included elderly (≥35 years) nulliparous and control group included non-elderly (<35 years) nulliparous women. Primary outcome was IoL failure rate and secondary outcome was cesarean delivery rate. Outcomes were compared between the groups by univariate analysis followed by regression analysis to adjust results to potential confounders.

Results: Of 537 women undergoing IoL, 69 (12.8%) were elderly. The univariate analysis demonstrated no difference in IoL failure rate (26.5% versus 34.8%, p?=?0.502) between groups. However, elderly nulliparous women had higher rates of cesarean delivery (36.2% versus 21.4%, p?=?0.009). This difference was no longer significant after adjustment for maternal body mass index, indication for delivery, birth weight and gestational age at delivery.

Conclusion: Among nulliparous women, older maternal age is not associated with higher rates of IoL failure or cesarean deliveries.     

Is preeclampsia associated with an increased risk of cesarean delivery if labor is induced?

Objective.?To determine whether preeclampsia is associated with an increased risk of cesarean delivery if labor is induced.

Methods.?This retrospective cohort study of 3505 women ≥24 weeks gestation with singleton pregnancies undergoing labor induction compares cesarean delivery rates between preeclamptics and non-preeclamptics. Multivariable logistic regression analysis was used to control for potential confounders including unfavorable cervix (Bishop score ≤5), method of labor induction, maternal age, parity, gestational age, race/ethnicity, epidural use, medical insurance, and marital status.

Results.?Among term nulliparous women undergoing labor induction, preeclamptics had a higher cesarean delivery rate then non-preeclamptics (81/267, 30% vs. 363/1568, 23%; p?=?0.011), as did preeclamptic compared with non-preeclamptic women who were term and multiparous (10/64, 16% vs. 55/900, 6%, p?=?0.003). Preterm preeclamptics also had more cesarean deliveries compared with non-preeclamptics among nulliparous (48/164, 29% vs. 16/245, 7%; p?<?0.001) and multiparous (13/72, 18% vs. 18/225, 8%; p?=?0.015) women. In multivariable analysis, preeclampsia still conferred an increased risk of cesarean delivery if labor was induced (adjusted odd ratio?=?1.90, 95% CI 1.45–2.48).

Conclusion.?Women with preeclampsia undergoing labor induction had higher cesarean delivery rates compared with non-preeclamptics regardless of parity or gestational age. However, the majority of women with preeclampsia still had successful vaginal deliveries.     

Three-dimensional ultrasound power Doppler assessment of the cervix: comparison between nulliparas and multiparas

AIM: To assess the sonographic cervical characteristics between nulliparous and multiparous women. SUBJECT AND METHODS: Transvaginal three-dimensional ultrasound and power Doppler using the virtual organ computer-aided analysis (VOCAL) program were performed on 71 nulliparas and 59 multiparas at a mean gestational age of 25.3+/-7.9 weeks. We compared the cervical volume and power Doppler vascularization index (VI), flow index (FI), and vascularization-flow index (VFI) between nulliparas and multiparas. RESULTS: The mean cervical volume and mean VI, VFI, FI measurements were not significantly different between multiparas and nulliparas. CONCLUSION: Our observations suggest that the morphological changes in the cervix of parous women are merely configurational without a change in cervical mass and vascularization. These configurational changes might result from the inevitable cervical stretching during labor and represent a healing process that does not involve a subsequent change in mass or vascularity.     

Effect of availability of a parturient-elective regional labor pain relief service on the mode of delivery.

BACKGROUND/PURPOSE: Regional analgesia for labor pain relief is effective and widely used. This study evaluated the controversial association between mode of operative delivery and patient-elective labor regional analgesia. METHODS: We retrospectively compared the rates of instrumental vaginal and cesarean deliveries in parturients before the introduction, in the first 15 months after, and in the subsequent 36 months after the implementation of an elective labor regional analgesia service. A total of 9779 low-risk singleton cephalic pregnancies above 36 weeks of gestation were included. The maternal and fetal outcomes for parturients before the service was implemented and in those with or without pain relief service in the two postimplementation periods were analyzed. Multivariate logistic regression analyses were used to investigate the effects of maternal age, gestational weeks and newborn weight, in addition to regional analgesia, on the mode of delivery in nulliparous women. RESULTS: After adjusting for maternal age, gestational weeks, and newborn weight, no significant association was found between regional analgesia and cesarean delivery in nulliparas. Further, this lack of association was not affected by the receipt of regional analgesia in the early period of program implementation or in the period after staff had become familiar with the service. A higher rate of instrumental vaginal delivery was noted in nulliparas given regional analgesia. CONCLUSION: Regional analgesia for pain relief increased the likelihood of instrumental vaginal delivery, but did not increase the likelihood of cesarean delivery.     

Models for the prediction of successful induction of labor based on pre-induction sonographic measurement of cervical length.

OBJECTIVE: To examine the effect of pre-induction cervical length, parity, gestational age at induction, maternal age and body mass index (BMI) on the possibility of successful delivery in women undergoing induction of labor. METHODS: In 822 singleton pregnancies, induction of labor was carried out at 35 to 42(+6) weeks of gestation. The cervical length was measured by transvaginal sonography before induction. The effect of cervical length, parity, gestational age, maternal age and BMI on the interval between induction and vaginal delivery within 24 hours was investigated using Cox's proportional hazard model. The likelihood of vaginal delivery within 24 hours and risk for cesarean section overall and for failure to progress was investigated using logistic regression analysis. RESULTS: Successful vaginal delivery within 24 hours of induction occurred in 530 (64.5%) of the 822 women. Cesarean sections were performed in 161 (19.6%) cases, 70 for fetal distress and 91 for failure to progress. Cox's proportional hazard model indicated that significant prediction of the induction-to-delivery interval was provided by the pre-induction cervical length (HR=0.89, 95% CI 0.88-0.90, p<0.0001), parity (HR=2.39, 95% CI 1.98-2.88, p<0.0001), gestational age (HR=1.13, 95% CI 1.07-1.2, p=or<0.0001) and birth weight percentile (HR=0.995, 95% CI 0.99-0.995, p=0.001), but not by maternal age or BMI. Logistic regression analysis indicated that significant prediction of the likelihood of vaginal delivery within 24 hours was provided by pre-induction cervical length (OR=0.86, 95% CI 0.84-0.88, p<0.0001), parity (OR=3.59, 95% CI 2.47-5.22, p<0.0001) and gestational age (OR=1.19, 95% CI 1.07-1.32, p=or<0.0001) but not by BMI or maternal age. The risk of cesarean section overall was significantly associated with all the variables under consideration, i.e., pre-induction cervical length (OR=1.09, 95% CI 1.06-1.11, p<0.0001), parity (OR=0.25, 95% CI 0.17-0.38, p<0.0001), BMI (OR=1.85, 95% CI 1.24-2.74, p=0.0024), gestational age (OR=0.88, 95% CI 0.78-0.98, p=0.0215) and maternal age (OR=1.04, 95% CI 1.01-1.07, p=0.0192). The risk of cesarean section for failure to progress was also significantly associated with pre-induction cervical length (OR=1.11, 95% CI 1.07-1.14, p<0.0001), parity (OR=0.26, 95% CI 0.15-0.43, p<0.0001), gestational age (OR=0.83, 95% CI 0.73-0.96, p=0.0097) and BMI (OR=2.07, 95% CI 1.27-3.37, p=0.0036). CONCLUSION: In women undergoing induction of labor, pre-induction cervical length, parity, gestational age at induction, maternal age and BMI have a significant effect on the interval between induction and delivery within 24 hours, likelihood of vaginal delivery within 24 hours and the risk of cesarean section.     

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.