Risk factors for arrest of descent during the second stage of labor.

OBJECTIVE: To define obstetrical risk factors for arrest of descent during the second stage of labor and to determine perinatal outcome. STUDY DESIGN: All singleton, vertex, term deliveries with an unscarred uterus, between the years 1988 and 1999 were included. Univariable and multivariable analysis were performed to investigate independent risk factors associated with arrest of descent during the second stage of labor and the perinatal outcome. RESULTS: The study included 93266 deliveries, of these 1545 (1.7%) were complicated with arrest of descent during the second stage of labor. Using a multivariable analysis, the following obstetric risk factors were found to be significantly associated with arrest of descent: nulliparity (OR=7.8, 95% CI=6.9-8.7; P<0.001), birth weight >4 kg (OR=2.3, 95% CI=1.9-2.8; P<0.001), epidural analgesia (OR=1.8, 95% CI=1.6-2.0; P<0.001), hydramnios (OR=1.6, 95% CI=1.3-2.0; P<0.001), hypertensive disorders (OR=1.5, 95% CI=1.3-1.8; P<0.001), gestational diabetes A1 and A2 (OR=1.5, 95% CI=1.2-1.8; P<0.001), male gender (OR=1.4, 95% CI=1.2-1.5; P<0.001), premature rupture of membranes (PROM, OR=1.3, 95% CI=1.04-1.6; P=0.021), and induction of labor (OR=1.2, 95% CI=1.02-1.4; P=0.030). Deliveries complicated by arrest of descent resulted in cesarean section in 20.6%, vacuum extraction in 74.0%, and forceps delivery in 5.4%. Newborns delivered after arrest of descent during the second stage of labor had significantly higher rates of low Apgar scores (<7) at 1 and 5 min, as compared to the controls (12.7 vs. 2.1%, P<0.001; and 0.9 vs. 0.2%, P<0.001, respectively). Nevertheless, no significant differences were noted between the groups regarding perinatal mortality (0.38 vs. 0.44%; P=0.759). CONCLUSIONS: Major risk factors for arrest of descent during the second stage of labor were nulliparity, fetal macrosomia, epidural analgesia, hydramnios, hypertensive disorders and gestational diabetes mellitus. These risk factors should be carefully evaluated during pregnancy in order to actively manage high-risk pregnancies.     

Gender does matter in perinatal medicine

OBJECTIVE: To investigate complications and outcome of pregnancies with male and female fetuses. METHODS: A population-based study comparing all singleton deliveries between the years 1988 and 1999 was performed. We compared pregnancies with male vs. female fetuses. Patients with a previous cesarean section (CS) were excluded from the study. Statistical analyses with the Mantel-Haenszel technique and multiple logistic regression models were performed to control for confounders. RESULTS: During the study period there were 55,891 deliveries of male and 53,104 deliveries of female neonates. Patients carrying male fetuses had higher rates of gestational diabetes mellitus (OR = 1.1; 95% CI 1.01-1.12; p = 0.012), fetal macrosomia (OR = 2.0; 95% CI 1.8-2.1; p < 0.001), failure to progress during the first and second stages of labor (OR = 1.2; 95% CI 1.1-1.3; p < 0.001 and OR = 1.4; 95% CI 1.3-1.5; p < 0.001, respectively), cord prolapse (OR = 1.3; 95% CI 1.1-1.6; p = 0.014), nuchal cord (OR = 1.2; 95% CI 1.1-1.2; p < 0.001) and true umbilical cord knots (OR = 1.5; 95% CI 1.3-1.7; p < 0.001). Higher rates of CS were found among male compared with female neonates (8.7 vs. 7.9%; OR = 1.1; 95% CI 1.06-1.16; p < 0.001). Using three multivariate logistic regression models and controlling for birth weight and gestational age, male gender was significantly associated with non-reassuring fetal heart rate patterns (OR = 1.5; 95% CI 1.4-1.6; p < 0.001), low Apgar scores at 5 min (OR = 1.5; 95% CI 1.3-1.8; p < 0.001) and CS (OR = 1.2; 95%CI 1.2-1.3; p < 0.001). Controlling for possible confounders like gestational diabetes, cord prolapse, failed induction, nonprogressive labor, fetal macrosomia, nuchal cord and true umbilical cord knots using the Mantel-Haenszel technique did not change the significant association between male gender and CS. CONCLUSION: Male gender is an independent risk factor for adverse pregnancy outcome.     

Precipitate labor: higher rates of maternal complications

OBJECTIVE: The study was aimed to identify risk factors and to elucidate pregnancy outcome following precipitate labor, i.e. expulsion of the fetus within less than 3 h of commencement of contractions. METHODS: A comparison of patients with and without precipitate labor, delivered during the years 1988-2002, was conducted. Patients who underwent cesarean deliveries were excluded from the analysis. A multiple logistic regression model, with backward elimination, was performed to investigate independent risk factors for precipitate labor. RESULTS: The number of vaginal deliveries that occurred during the study period was 137,171. Of these, 99 were precipitate. Independent risk factors for precipitate labor, using a backward, stepwise multivariate analysis were: placental abruption (odds ratio (OR) = 30.9, 95% confidence interval (CI) 15.9-60.4, P < 0.001); fertility treatments (OR = 3.9, 95% CI 1.7-9.0, P = 0.002); chronic hypertension (OR = 3.1, 95% CI 1.2-7.8, P = 0.015); intrauterine growth restriction (IUGR) (OR = 2.9, 95% CI 1.2-6.8, P = 0.014); prostaglandin E2 induction (OR = 1.9, 95% CI 1.1-3.5, P = 0.045); birth weight < 2,500 g (OR = 1.8, 95% CI 1.1-3.1, P = 0.020); and nulliparity (OR = 1.7, 95% CI 1.1-2.6, P = 0.014). No significant differences were noted between the groups regarding perinatal complications such as meconium stained amniotic fluid, perinatal mortality and low Apgar scores. However, there were higher rates of maternal complications in the precipitate labor group such as cervical tears and grade 3 perineal tears (18.2% versus 0.3%, P < 0.001; and 2.0% versus 0.1%, P < 0.001, respectively), post-partum hemorrhage (13.1% versus 0.4%, P < 0.001); retained placenta (2.0% versus 0.5%, P = 0.02); the need for revision of uterine cavity and packed-cells transfusions (34.3% versus 4.9%, P < 0.001; and 11.1% versus 1.1%, P < 0.001, respectively) and prolonged hospitalization (27.6% versus 19.2%, P = 0.035) as compared to the controls. CONCLUSION: Precipitate labor is associated with higher rates of maternal complications.     

Umbilical cord prolapse and perinatal outcomes.

OBJECTIVES: To determine obstetric risk factors and perinatal outcomes of pregnancies complicated by umbilical cord prolapse. METHODS: A population-based study was performed comparing all deliveries complicated by cord prolapse to deliveries without this complication. Statistical analysis was performed using multiple logistic regression models. RESULTS: Prolapse of the umbilical cord complicated 0.4% (n=456) of all deliveries included in the study (n=121,227). Independent risk factors for cord prolapse identified by a backward, stepwise multivariate logistic regression model were: malpresentation (OR=5.1; 95% CI 4.1-6.3), hydramnios (OR=3.0; 95% CI 2.3-3.9), true knot of the umbilical cord (OR=3.0; 95% CI 1.8-5.1), preterm delivery (OR=2.1; 95% CI 1.6-2.8), induction of labor (OR=2.2; 95% CI 1.7-2.8), grandmultiparity (>five deliveries, OR=1.9; 95% CI 1.5-2.3), lack of prenatal care (OR=1.4; 95% CI 1.02-1.8), and male gender (OR=1.3; 95% CI 1.1-1.6). Newborns delivered after umbilical cord prolapse graded lower Apgar scores, less than 7, at 5 min (OR=11.9, 95% CI 7.9-17.9), and had longer hospitalizations (mean 5.4+/-3.5 days vs. 2.9+/-2.1 days; P<0.001). Moreover, higher rates of perinatal mortality were noted in the cord prolapse group vs. the control group (OR=6.4, 95% CI 4.5-9.0). Using a multiple logistic regression model controlling for possible confounders, such as preterm delivery, hydramnios, etc., umbilical cord prolapse was found to be an independent contributing factor to perinatal mortality. CONCLUSIONS: Prolapse of the umbilical cord is an independent risk factor for perinatal mortality.     

Third degree perineal tears in a university medical center where midline episiotomies are not performed

Objective Midline episiotomy is a known major risk factor for severe perineal lacerations. The study was aimed to define obstetric risk factors for third-degree perineal tears in a university medical center where midline episiotomies are not performed.Study design A comparison between vaginal deliveries complicated with third-degree perineal tears and deliveries without third-degree perineal tears was performed. Deliveries occurred between the years 1988–1999 in a tertiary medical center. Multiple gestations, preterm deliveries (<37 weeks gestation), cesarean deliveries and cases of shoulder dystocia were excluded from the analysis. A multiple logistic regression model was constructed in order to find independent risk factors for third-degree perineal tears. Odds ratios (OR) and their 95% confidence interval (CI) were calculated from the regression coefficient.Results During the study period, 79 (0.1%) consecutive cases of third degree perineal tears were identified. Significant risk factors from the univariate analysis were fetal macrosomia (OR 2.7, 95%CI 1.2–5.5), nulliparity (OR 2.9, 95%CI 1.8–4.6), labor induction (OR 1.9, 95%CI 1.0–3.5), failure of labor to progress during the second stage (OR 10.8, 95%CI 5.4–21.1), non-reassuring fetal heart rate patterns (OR 11.7, 95%CI 6.1–21.5), mediolateral episiotomy (OR 2.8, 95%CI 1.8–4.5), vacuum extraction (OR 10.6, 95%CI 6.1–18.3), and forceps delivery (OR 29.2, 95%CI 7.3–97.2). However, using a multivariable analysis, only fetal macrosomia (OR 2.5, 95%CI 1.2–4.9), vacuum extraction (OR 8.2, 95%CI 4.7–14.5), and forceps delivery (OR 26.7, 95%CI 8.0–88.5) remained as independent risk factors. The combined risk for instrumental deliveries of macrosomic newborns was 8.6 (95% CI 1.2–62.5; p=0.010).Conclusions After adjustment for possible confounding variables, mediolateral episiotomy per se was not an independent risk factor for third-degree perineal tears. Instrumental vaginal deliveries of macrosomic fetuses should be avoided whenever possible to decrease the occurrence of third-degree perineal tears.Presented in part at the Society for Gynecologic Investigation 50th Annual Scientific Meeting, Washington, DC, 27–30 March 2003     

Obstetric characteristics and perinatal outcome of pregnancies with uterine leiomyomas

OBJECTIVE: To determine the rate, obstetric characteristics and perinatal outcome of pregnancies with uterine leiomyomas. STUDY DESIGN: A population-based study comparing all singleton deliveries between the years 1988 and 1999 in women with and without uterine leiomyomas was performed. Patients lacking prenatal care were excluded from the analysis. Multivariable analysis, adjusting for possible confounders, such as maternal age, parity and gestational age, was performed to investigate associations between uterine leiomyomas and selected outcomes. RESULTS: There were 105,909 singleton deliveries with 690 (0.65%) complicated by uterine leiomyomas during the study period. Using a multivariable analysis, the following conditions were significantly associated with uterine leiomyomas: nulliparity (odds ratio [OR]=4.0, 95% confidence interval [CI] 3.3-4.7, P<.001), chronic hypertension (OR=1.9, 95% CI 1.6-2.4, P<.001), hydramnios (OR=1.5, 95% CI 1.2-2.0, P<.001), diabetes mellitus (OR=1.4, 95% CI 1.1-1.7, P=.001) and advanced maternal age (OR=1.2, 95% CI 1.1-1.2, P<.001). Higher rates of perinatal mortality (2.2% vs. 1.2%, OR=1.8, 95% CI 1.1-3.2, P<.001) were found in the uterine leiomyoma group as compared to the control group. While adjusting for maternal age, parity, gestational age and malpresentation, pregnancies with uterine leiomyomas had higher rates of cesarean deliveries (OR=6.7, 95% CI 5.5-8.1, P<.001), placental abruption (OR=2.6, 95% CI 1.6-4.2, P<.001) and preterm deliveries (<36 weeks' gestation, OR=1.4, 95% CI 1.1-1.7, P=.009) as compared to pregnancies without uterine leiomyomas. Conversely, no significant differences were noted regarding perinatal mortality (OR=1.4, 95% CI 0.7-2.8, P=.351) after controlling for maternal age, parity and gestational age using a multivariable analysis. CONCLUSION: Uterine leiomyomas increase the risk of adverse pregnancy outcomes, thus emphasizing the importance of appropriate intrapartum management of these high-risk pregnancies.     

Uterine rupture: risk factors and pregnancy outcome

OBJECTIVES: This study aimed at determining risk factors and pregnancy outcome in women with uterine rupture. STUDY DESIGN: We conducted a population-based study, comparing all singleton deliveries with and without uterine rupture between 1988 and 1999. RESULTS: Uterus rupture occurred in 0.035% (n=42) of all deliveries included in the study (n=117,685). Independent risk factors for uterine rupture in a multivariable analysis were as follows: previous cesarean section (odds ratio [OR]=6.0, 95% CI 3.2-11.4), malpresentation (OR=5.4, 95% CI 2.7-10.5), and dystocia during the second stage of labor (OR=13.7, 95% CI 6.4-29.3). Women with uterine rupture had more episodes of postpartum hemorrhage (50.0% vs 0.4%, P<.01), received more packed cell transfusions (54.8% vs 1.5%, P<.01), and required more hysterectomies (26.2% vs 0.04%, P<.01). Newborn infants delivered after uterine rupture were more frequently graded Apgar scores lower than 5 at 5 minutes and had higher rates of perinatal mortality when compared with those without rupture (10.3% vs 0.3%, P<.01; 19.0% vs 1.4%, P<.01, respectively). CONCLUSION: Uterine rupture, associated with previous cesarean section, malpresentation, and second-stage dystocia, is a major risk factor for maternal morbidity and neonatal mortality. Thus, a repeated cesarean delivery should be considered among parturients with a previous uterine scar, whose labor failed to progress.     

Short stature--an independent risk factor for Cesarean delivery

OBJECTIVE: The present study was aimed to investigate pregnancy outcome of patients with short stature (height<155 cm), and specifically to elucidate if patients with short stature are at an increased risk for Cesarean section (CS) even after controlling for labor dystocia. METHODS: A population-based study comparing pregnancy outcome of patients with and without short stature, was performed. Deliveries occurred during the years 1988-2002, in a tertiary medical center. Stratified analyses, using the Mantel-Haenszel technique, and a multiple logistic regression model were performed to control for confounders. RESULTS: During the study period, 159,210 deliveries occurred. Of these, 5822 (3.65%) were of patients with short stature. Patients with short stature had statistically significant higher rates of CS compared with patients>or=155 cm (21.3% versus 11.9%, odds ratio (OR)=2.0; 95% confidence interval (CI): 1.9-2.1; P<0.001). Furthermore, there patients had higher rated of previous deliveries by CS (17.5% versus 10.3%, OR=1.8; 95% CI: 1.7-2.0; P<0.001), intrauterine growth restriction (IUGR, 3.2% versus 1.9%, OR=1.7; 95% CI: 1.4-1.9; P<0.001), premature rupture of membranes (PROM, 7.1% versus 5.6%, OR=1.3; 95% CI: 1.2-1.4; P<0.001), failed induction (0.7% versus 0.4%, OR=2.0; 95% CI: 1.5-2.8; P<0.001), labor dystocia (6.1% versus 3.5%, OR=1.8; 95% CI: 1.6-2.0; P<0.001), mal-presentations (7.6% versus 6.1%, OR=1.3; 95% CI: 1.1-1.4; P<0.001), and cephalopelvic disproportion (CPD, 0.9% versus 0.3%, OR=2.6; 95% CI: 1.9-3.4; P<0.001). No significant differences were noted between the groups regarding perinatal complications such as low birth-weight, meconium-stained amniotic fluid, perinatal mortality, and low Apgar scores at 5 min. Controlling for possible confounders such as previous CS, IUGR, PROM, failed induction, labor dystocia, mal-presentations and CPD, using the Mantel-Haenszel technique, did not change the significant association between short stature and CS. Moreover, a multiple logistic regression model was constructed with CS as the outcome variable, controlling for all these confounders. The model found short stature to be an independent risk factor for CS (OR=1.7; 95% CI: 1.6-1.9; P<0.001). CONCLUSION: Short stature is an independent risk factor for Cesarean delivery. Further studies investigating the actual indication for CS should be performed in order to make an informed recommendation regarding the preferred mode of delivery in short parturient women.     

Pregnancy outcome of asthmatic patients: a population-based study.

OBJECTIVE: To investigate pregnancy outcome of asthmatic patients. METHODS: A retrospective population-based study comparing all singleton pregnancies in women with and without asthma was conducted. Patients lacking prenatal care (less than three visits in prenatal care facilities) were excluded from the study. Deliveries occurred during the years 1988-2002. Stratified analysis, using a multiple logistic regression model was performed to control for confounders. RESULTS: During the study period 139 168 singleton deliveries occurred, of which 1.4% in asthmatic patients (n = 963). Using a multivariate analysis, with backward elimination, the following complications were significantly associated with maternal asthma: diabetes mellitus (OR = 1.8, 95%CI 1.5-2.0, p < 0.001), fertility treatments (OR = 1.6, 95%CI 1.3-2.1, p < 0.001), intrauterine growth restriction (IUGR) (OR = 1.5, 95%CI 1.1-1.9, p = 0.004), hypertensive disorders (OR = 1.5, 95%CI 1.2-1.7, p < 0.001) and premature rupture of membranes (OR = 1.2, 95%CI 1.1-1.5, p = 0.013). Higher rates of cesarean deliveries were found among asthmatic patients as compared to the controls (17.1% vs. 11.4%, p < 0.001). This association persisted even after controlling for possible confounders such as failure to progress in labor, mal-presentations, IUGR, etc. No significant differences regarding low Apgar scores (less than 7) at 1 and 5 minutes were noted between the groups (3.9% vs. 4.4%, p = 0.268 and 0.4% vs. 0.6%, p = 0.187, respectively). Likewise, the perinatal mortality rate was similar among patients with and without asthma (1.3% vs. 1.3%, p = 0.798). CONCLUSION: Pregnant women with asthma are at an increased risk for adverse maternal outcome. This association persists after controlling for variables considered to co-exist with maternal asthma. However, perinatal outcome is favorable. Careful surveillance is required in pregnancies of asthmatic patients, for early detection of possible complications.     

Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001.

OBJECTIVE: To identify maternal and fetal risk factors associated with persistent occiput posterior position at delivery, and to examine the association of occiput posterior position with subsequent obstetric outcomes. METHODS: This is a retrospective cohort study of 30 839 term, cephalic, singleton births. Women with persistent occiput posterior (OP) position at delivery were compared to those with occiput anterior (OA) position. Demographics, obstetric history, and labor management were evaluated and subsequent obstetric outcomes examined. Potential confounding variables were controlled for using multivariate logistic regression analysis. RESULTS: The overall frequency of OP position was 8.3% in the study population. When compared to Caucasians, a higher rate of OP was observed among African-Americans (OR = 1.4, 95% CI 1.25-1.64) while no other racial/ethnic differences were noted. Other associated factors included nulliparity, maternal age > or =35, gestational age > or =41 weeks, and birth weight >4000 g, as well as artificial rupture of the membranes (AROM) and epidural anesthesia (p < 0.001 for all). Persistent OP was associated with increased rates of operative vaginal (OR = 4.14, 95% CI 3.57-4.81) and cesarean deliveries (OR = 13.45, 95% CI 11.94-15.15) and other peripartum complications including third or fourth degree perineal lacerations (OR = 2.38, 95% CI 2.03-2.79), and chorioamnionitis (OR = 2.10, 95% CI 1.81-2.44). CONCLUSION: Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications. This information can be useful in counseling patients regarding risks and associated outcomes of persistent OP position.     

Is the risk of obstetric anal sphincter injuries increased in vaginal twin deliveries?

Objective: Vaginal twin deliveries have a higher rate of intrapartum interventions. We aimed to determine whether these characteristics are associated with an increased rate of obstetric anal sphincter injuries compared with singleton.

Study design: Retrospective study of all twin pregnancies undergoing vaginal delivery trial was conducted from January 2000–September 2014. Sphincter injury rate compared with all concurrent singleton vaginal deliveries. Multivariable analysis was used to determine twin delivery association with sphincter injuries while adjusting for confounders.

Results: About 717 eligible twin deliveries. Outcome was compared with 33?886 singleton deliveries. Twin pregnancies characterized by a higher rate of nulliparity (54.8% versus 49.5%, p?=?0.005), labor induction (42.7% versus 29.1%, p?<?0.001), and instrumental deliveries (27.5% versus 16.7%, p?<?0.001), lower gestational (34.6?±?3.3 versus 38.8?±?2.3, p?<?0.001), and lower birth weight. Total breech extraction was performed in 29.0% (208/717) of twin deliveries. Overall obstetric sphincter injury rate was significantly lower in the twins group (2.8% versus 4.4%, p?=?0.03, OR?=?0.6, 95% CI 0.4–0.9), due to lower rate of 3rd degree tears in twins versus singletons (2.2% versus 4.0%, p?=?0.02), rate of 4th degree tears similar among the groups (0.6% versus 0.4%, p?=?0.5). In multivariable analysis, sphincter injuries were associated with nulliparity (OR?=?3.9, 95% CI 3.4–4.5), forceps (OR?=?6.8, 95% CI 5.8–7.8), vacuum (OR?=?2.9, 95% CI 2.5–3.3), earlier gestational age (OR?=?0.2, 95% CI 0.1–0.3), episiotomy (OR?=?0.8, 95% CI 0.7–0.9), and birth weight over 3500?g (OR?=?1.8, 95% CI 1.6–2.0). However, the association between twins (versus singletons) deliveries and sphincter injuries was lost after adjustment for delivery gestational age (OR?=?0.7, 95% CI 0.4–1.2).

Conclusion: Despite a higher rate of intrapartum interventions, the rate of sphincter injuries is lower in twins versus singleton deliveries, mainly due to a lower gestational age at delivery.     

Obstetric risk factors and outcome of pregnancies complicated with early postpartum hemorrhage: a population-based study.

OBJECTIVE: The study was aimed to identify obstetric risk factors for early postpartum hemorrhage (PPH) in singleton gestations and to evaluate pregnancy outcome. STUDY DESIGN: A comparison between consecutive singleton deliveries with and without early PPH was performed. Deliveries occurred during the years 1988-2002 in a tertiary medical center. A multivariate logistic regression model was constructed in order to define independent risk factors for PPH. RESULTS: Postpartum hemorrhage complicated 0.4% (n = 666) of all deliveries enrolled in the study (n = 154 311). Significant risk factors for PPH, identified using a multivariable analysis, were: retained placenta (OR 3.5, 95%CI 2.1-5.8), failure to progress during the second stage of labor (OR 3.4, 95%CI 2.4-4.7), placenta accreta (OR 3.3, 95%CI 1.7-6.4), lacerations (OR 2.4, 95%CI 2.0-2.8), instrumental delivery (OR 2.3, 95%CI 1.6-3.4), large for gestational age (LGA) newborn (OR 1.9, 95%CI 1.6-2.4), hypertensive disorders (OR 1.7, 95%CI 1.2-2.1), induction of labor (OR 1.4, 95%CI 1.1-1.7) and augmentation of labor with oxytocin (OR 1.4, 95%CI 1.2-1.7). Women were assigned into three different groups according to the assessed severity of PPH, assuming that the severe cases were handled by revision of the birth canal under anesthesia, and the most severe cases required in addition treatment with blood products. A significant linear association was found between the severity of bleeding and the following factors: vacuum extraction, oxytocin augmentation, hypertensive disorders as well as perinatal mortality, uterine rupture, peripartum hysterectomy and uterine or internal iliac artery ligation (p < 0.001 for all variables). CONCLUSION: Hypertensive disorder, failure to progress during the second stage of labor, oxytocin augmentation, vacuum extraction and LGA were found to be major risk factors for severe PPH. Special attention should be given after birth to hypertensive patients, and to patients who underwent induction of labor or instrumental delivery, as well as to those delivering LGA newborns.     

Maternal rehospitalization after singleton term vaginal delivery

Objective: To determine risk factors for maternal rehospitalization after term vaginal delivery. Study design: The study group consisted of all women who were rehospitalized following singleton vaginal deliveries during 1996-1998 (n = 194). The control group consisted of 427 women who were not rehospitalized during the same period. Results: The incidence of rehospitalization was 0.75% (194/25 885). Maternal chronic diseases, preterm contractions and pre-eclampsia rates were significantly higher among the study group as compared to the controls (25.3% vs. 8.4%, p < 0.001; 6.7% vs. 2.8%, p = 0.022; 9.3% vs. 4.9%, p = 0.037, respectively). Duration of labor was significantly longer in the study group as opposed to the controls (379 ± 406 min vs. 259 ± 276 min, p < 0.001). The rates of postpartum hemorrhage, blood transfusion and antibiotic treatment during delivery hospitalization were significantly higher among the study group (1.5% vs. 0.2%, p = 0.021; 4.6% vs. 0.7%, p < 0.001; 26.8% vs. 14.1%, p < 0.001, respectively). Using a forward logistic regression analysis, prolonged labor and blood transfusion during labor were found as independent risk factors associated with rehospitalization (OR 1.001, 95% CI 1.001-1.002, p = 0.001; OR 4.751, 95% CI 1.698-13.292, p = 0.003). In contrast, vertex presentation had a protective effect against rehospitalization (p = 0.027, OR 0.084, 95% CI 0.009-0.758). Conclusions: Blood transfusion and prolonged labor are independent risk factors for rehospitalization after term vaginal delivery. Special attention should be given during the early postpartum period to patients receiving blood transfusions and those with prolonged deliveries, in order to reduce rehospitalization rates.     

Obstetric characteristics and neonatal outcome of unplanned out-of-hospital term deliveries: a prospective, case-control study

OBJECTIVE: To describe the obstetric characteristics and neonatal outcomes in unplanned out-of-hospital deliveries. STUDY DESIGN: Obstetric characteristics and neonatal outcomes were compared between 151 consecutive parturients with unplanned, out-of-hospital term deliveries and 151 hospital term deliveries. RESULTS: Women who delivered out of hospital tended to be older (32 +/- 5.5 vs. 28 +/- 5.0 years, p = 0.046) and less educated (4.4 +/- 5.1 vs. 6.5 +/- 5.0 years, p = 0.005) as compared to women who delivered in the hospital. Unplanned out-of-hospital deliveries resulted in statistically significant higher rate of low-birth-weight newborns (< 2,500 g) (OR= 3.9, 95% CI 2.0-7.7, p<0.001), postpartum hemorrhage (OR = 8.4, 95% CI 1.1-181.1, p = 0.018) and trended for higher rate of manual lysis of retained placenta and membranes (4.0% vs. 0%, p = 0.013). Higher rates of admission to the neonatal intensive care unit due to neonatal complications, such as polycythemia (12.6% vs. 0%, p < 0.001), hypoglycemia (9.3% vs. 0.6%, p = 0.001) and convulsions (3.3% vs. 0%, p = 0.024), were noted in the out-of-hospital delivery group as compared to the controls. Using a multivariable analysis, lower educational level (OR = 0.4, 95% CI 0.3-0.4, p < 0.001), maternal age > 35 (OR = 6.2, 95% CI 2.3-16.7, p < 0.001) and high parity (OR = 7.9, 95% CI 4.9-12.9, p<0.001) were found to be independent risk factors for an unplanned outof hospital delivery. CONCLUSION: Unplanned out-of-hospital birth is an important risk factor for such complications as postpartum hemorrhage, low birth weight and adverse neonatal outcome.     

Nuchal cord is not associated with adverse perinatal outcome

Objective: The present study was aimed at evaluating the outcome of pregnancies with nuchal cord. Methods: A retrospective population-based study of all deliveries during the years 1988–2003 in a tertiary medical center was conducted. Immediate perinatal outcome of patients with and without nuchal cord was compared. Results: Of 166,318 deliveries during the study period, 14.7% had a nuchal cord, documented at birth (n=24,392). Higher rates of labor induction and non-reassuring fetal heart rate patterns were noted among pregnancies with nuchal cord as compared with the control group (30.1% vs. 24.2%; OR=1.3, 95% CI 1.3–1.4, P<0.001 and 4.5% vs. 2.6%; OR=1.8, 95% CI 1.6–1.9, P<0.001; respectively). The cesarean delivery rate was significantly lower among pregnancies with nuchal cord (11.5% vs. 12.7%; OR=0.9, 95% CI 0.8–0.9, P=0.001). Although 1 min Apgar scores lower than 7 were more common in pregnancies with nuchal cord (4.8% vs. 4.4%; OR=1.1, 95% CI 1.01–1.2, P=0.008), these pregnancies actually had lower rates of 5 min Apgar scores less than 7 (0.5% vs. 0.7%; OR=0.8, 95% CI 0.6–0.9, P=0.004). Likewise, the perinatal mortality rate was significantly lower in pregnancies with nuchal cord as compared with the comparison group (11/1,000 vs. 16/1,000; OR=0.7, 95% CI 0.6–0.8, P=0.001). Conclusions: Nuchal cord is not associated with adverse perinatal outcome. Thus, labor induction in such cases is probably unnecessary.Presented in part at the 15th World Congress on Ultrasound in Obstetrics and Gynecology 25–29 September 2005, Vancouver, Canada.     

Using anovaginal distance at the beginning of labor to predict the likelihood of instrumental delivery

OBJECTIVE: To investigate whether anovaginal distance in parturients has an impact on the instrumental delivery rate. STUDY DESIGN: In this study with prospective data collection and a convenience sample, 400 parturients planning for vaginal delivery at term with a singleton fetus in vertex presentation were enrolled. Anovaginal distance was measured in the lithotomy position during the latent phase of labor or early first stage. This distance is thought to reflect the angle of inclination of the birth canal axis. RESULTS: At the cutoff point of 25 mm for anovaginal distance, the odds ratio for instrumental delivery was 2.5 (95% CI 1.48-6.6, p<0.05). A final model of instrumental delivery, controlling for various confounding variables, correctly predicted 91.38% of the instrumental deliveries (p<0.0001). The variables anovaginal distance >25 mm (OR 2.9, 95% CI 1.2-6.7, p=0.01), parity (OR 0.54, 95% CI 0.29-0.99, p=0.046) and duration of second stage of labor (OR 1.01, 95% CI 1.004-1.01, p=0.001) significantly contributed to the prediction of instrumental delivery after controlling for the other parameters. CONCLUSION: Women with an anovaginal distance of >25 mm at the beginning of labor was 2.5 more likely to undergo instrumental delivery than were women with an anovaginal distance of <25 mm.     

Idiopathic bleeding during the second half of pregnancy as a risk factor for adverse perinatal outcome.

OBJECTIVE: To investigate pregnancy outcome in women suffering from idiopathic vaginal bleeding (IVB) during the second half of pregnancy. METHODS: A comparison between patients admitted to the hospital due to bleeding during the second half of pregnancy and patients without bleeding was performed. Patients lacking prenatal care as well as multiple gestations were excluded from the analysis. Stratified analyses using the Mantel-Haenszel technique and a multiple logistic regression model were performed to control for confounders. RESULTS: During the study period, 173,621 singleton deliveries occurred at our institute. Of these, 2077 (1.19%) were complicated with bleeding upon admission during the second half of pregnancy. After excluding cases with bleeding due to placental abruption, placenta previa, cervical problems, etc., 67 patients were classified as having IVB (0.038%). Independent risk factors associated with IVB, using a backward, stepwise multivariable analysis were oligohydramnios (OR=6.2; 95% CI 3.1-12.7; p < 0.001), premature rupture of membranes (OR=3.4; 95% CI 1.8-6.2; p < 0.001), intrauterine growth restriction (IUGR, OR 5.6; 95% CI 2.5-12.2; p < 0.001), and Jewish ethnicity (OR=1.9; 95% CI 1.0-3.5; p=0.036). These patients subsequently were more likely to deliver preterm (<37 weeks, 56.7% vs. 7.3%; mean gestational age of 33.6+/-5.7 weeks vs. 39.2+/-2.1 weeks; p < 0.001) and by cesarean delivery (CD, 35.8% vs. 12.1%, OR=4.0; 95% CI 2.4-6.6; p < 0.001). Higher rates of low Apgar scores (<7) at 1 and 5 minutes were noted in these patients (OR=10.3; 95% CI 5.9-17.8; p < 0.001 and OR=17.8; 95% CI 7.1-44.5; p < 0.001, respectively). Moreover, perinatal mortality rate among patients admitted due to idiopathic bleeding was significantly higher as compared to patients without bleeding (9.6% vs. 1.2%, OR=8.4; 95% CI 3.3-21.2; p < 0.001). However, when controlling for preterm delivery, using the Mantel-Haenszel technique, the association lost its significance. CONCLUSION: Idiopathic vaginal bleeding during the second half of pregnancy is a risk factor for adverse perinatal outcome, mostly due to its significant association with preterm delivery. Careful surveillance, including fetal monitoring, is suggested in these cases in order to reduce the adverse perinatal outcome.     

Identifying risk factors for peripartum cesarean hysterectomy. A population-based study

OBJECTIVE: To determine the incidence of, and obstetric risk factors for, emergency peripartum hysterectomy. STUDY DESIGN: A population-based study comparing all singleton deliveries between the years 1988 and 1999 that were complicated with peripartum hysterectomy to deliveries without this complication. Statistical analysis was performed with multiple logistic regression analysis. RESULTS: Emergency peripartum hysterectomy complicated 0.048% (n = 56) of deliveries in the study (n = 117,685). Independent risk factors for emergency peripartum hysterectomy from a backward, stepwise, multivariable logistic regression model were: uterine rupture (OR = 521.4, 95% CI 197.1-1379.7), placenta previa (OR = 8.2, 95% CI 2.2-31.0), postpartum hemorrhage (OR = 33.3, 95% CI 12.6-88.1), cervical tears (OR = 18.0, 95% CI 6.2-52.4), placenta accreta (OR = 13.2, 95% CI 3.5-50.0), second-trimester bleeding (OR = 9.5, 95% CI 2.3-40.1), previous cesarean section (OR = 6.9, 95% CI 3.7-12.8) and grand multiparity (> 5 deliveries) (OR = 3.4, 95% CI 1.8-6.3). Newborns delivered after peripartum hysterectomy had lower Apgar scores (< 7) at 1 and 5 minutes than did others (OR = 11.5, 95% CI 6.2-20.9 and OR = 27.4, 95% CI 11.2-67.4, respectively). In addition, higher rates of perinatal mortality were noted in the uterine hysterectomy vs. the comparison group (OR = 15.9, 95% CI 7.5-32.6). Affected women were more likely than the controls to receive packed-cell transfusions (OR = 457.7, 95% CI 199.2-1105.8) and had lower hemoglobin levels at discharge from the hospital (9.9 +/- 1.3 vs. 12.8 +/- 5.7, P < .001). CONCLUSION: Cesarean deliveries in patients with suspected placenta accreta, specifically those performed due to placenta previa in women with a previous uterine scar, should involve specially trained obstetricians. In addition, detailed informed consent about the possibility of emergency peripartum hysterectomy and its associated morbidity should be obtained.     

Does dystocia during labor pose a risk factor for another non-progressive labor during the subsequent delivery?

Objective: To establish whether failure to progress during labor poses a risk factor for another non-progressive labor (NPL) during the subsequent delivery.

Methods: A retrospective cohort study including singleton pregnancies that failed to progress during the previous labor and resulted in a cesarean section (CS) was conducted. Parturients were classified into three groups for both previous and subsequent labors: CS due to NPL stage I, stage II and an elective CS as a comparison group.

Results: Of 202?462 deliveries, 10?654 women met the inclusion criteria: 3068 women were operated due to NPL stage I and 1218 due to NPL stage II. The comparison group included 6368 women. Using a multivariable logistic regression models, NPL stage I during the previous delivery was found as an independent risk factor for another NPL stage I in the subsequent labor (adjusted odds ratio [OR]?=?2.9; 95% confidence interval [CI]?=?2.4–3.7; p?p?=?0.033; adjusted OR?=?5.3; 95% CI?=?3.7–7.5; p?Conclusion: A previous CS due to a NPL is an independent risk factor for another NPL in the subsequent pregnancy and for recurrent cesarean delivery.     

Outcome in obstetric care related to oxytocin use. A population-based study

BACKGROUND: The purpose of this study was to investigate the delivery outcome in relation to oxytocin use in labor. METHODS: We studied 106,755 deliveries from 1995 to 2002 in the Perinatal Revision South, a population-based register comprising information from 10 hospitals in southern Sweden. RESULTS: Oxytocin use in labor increased from 27.6% in 1995/96 to 33.2% in 2001/02 (p<0.000006). Oxytocin was administered to 47.7% of the nulliparas and 18.5% of the multiparas. There were large differences between hospitals (range among nulliparas: 32.6-60.4%; among multiparas: 13.9-27.0%). After exclusion of deliveries with induction of labor and deliveries lasting >12 h, there was a significant association between oxytocin use and Apgar score < 7 at 5 min (OR 2.3; 95% CI 1.8-2.9), need for neonatal intensive care (OR 1.6; 95% CI 1.5-1.7), and operative delivery (OR 4.0; 95% CI 3.7-4.2). CONCLUSIONS: In deliveries with relatively short duration (< or =12 h), a significant association was seen between oxytocin use and adverse outcome. Even though the results are difficult to interpret, the significant difference between the use of oxytocin in different hospitals, as well as the increase of oxytocin use over time, calls for a randomized controlled study to elucidate the advantages and disadvantages of oxytocin use during labor and delivery.