Symptomatic pelvic organ prolapse: prevalence and risk factors in a population-based, racially diverse cohort

OBJECTIVE: To estimate the prevalence of and identify risk factors associated with symptomatic pelvic organ prolapse and level of distress in racially diverse women aged older than 40 years. METHODS: The Reproductive Risks for Incontinence Study at Kaiser is a population-based study of 2,001 randomly selected women. Symptomatic prolapse was determined by self-report of a feeling of bulge, pressure, or protrusion or a visible bulge from the vagina. Risk factors were assessed by self-report, interview, physical examination, and record review. Distress was assessed by self-report. Multivariable logistic regression analysis was used to identify independent risk factors. RESULTS: Symptomatic prolapse was reported by 118 (6%) women. Almost 50% of these women reported moderate or great distress, and 35% reported that the symptoms affected at least one physical, social or sexual activity. In multivariable analysis, the risk of prolapse was significantly increased in women with one (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.1-7.2), two (OR 4.1, 95% CI 1.8-9.5), and three or more (OR 5.3, 95% CI 2.3-12.3) vaginal deliveries compared with nulliparous women. Irritable bowel syndrome, constipation, and self-reported fair or poor health status were strongly associated with prolapse, with ORs of 2.8 (95% CI 1.7-4.6), 2.5 (95% CI 1.7-3.7), and 2.3 (95% CI 1.1-4.9), respectively. African-American women were significantly less likely to report symptomatic prolapse compared with white women (OR 0.4, 95% CI 0.2-0.8). CONCLUSION: Symptomatic prolapse is less common among African-American women and more common among women with a prior vaginal delivery, poor health status, constipation, or irritable bowel syndrome. Nearly one half of women with symptomatic prolapse are substantially bothered by their symptoms.     

Pelvic organ prolapse in nulliparous women and their parous sisters

OBJECTIVE: To investigate the role of vaginal delivery and familial factors in the development of pelvic organ prolapse by comparing the prevalence of this condition in nulliparous women and their parous sisters. METHODS: Pairs of nulliparous and parous postmenopausal sisters were recruited for assessment of pelvic organ prolapse. One hundred one sister pairs underwent clinical evaluation. Pelvic organ prolapse was recorded using the Pelvic Organ Prolapse Quantification System. RESULTS: The majority of women had no pelvic organ prolapse. By compartment there was a 74.3% to 91.1% concordance in prolapse stage within sister pairs. In discordant sister pairs, the parous sister was found to have the more advanced prolapse 88% of the time. CONCLUSION: High concordance of pelvic organ prolapse in nulliparous and parous sister pairs suggests a familial predisposition toward developing this condition. However, vaginal delivery does appear to confer a risk for more advanced pelvic organ prolapse. LEVEL OF EVIDENCE: II-2.     

Parity, mode of delivery, and pelvic floor disorders

OBJECTIVE: This study aimed to assess the associations between parity, mode of delivery, and pelvic floor disorders. METHODS: The prevalence of pelvic organ prolapse, stress urinary incontinence, overactive bladder, and anal incontinence was assessed in a random sample of women aged 25-84 years by using the validated Epidemiology of Prolapse and Incontinence Questionnaire. Women were categorized as nulliparous, vaginally parous, or only delivered by cesarean. Adjusted odds ratios and 95% confidence intervals (CIs) for each disorder were calculated with logistic regression, controlling for age, body mass index, and parity. RESULTS: In the 4,458 respondents the prevalence of each disorder was as follows: 7% prolapse, 15% stress urinary incontinence, 13% overactive bladder, 25% anal incontinence, and 37% for any one or more pelvic floor disorders. There were no significant differences in the prevalence of disorders between the cesarean delivery and nulliparous groups. The adjusted odds of each disorder increased with vaginal parity compared with cesarean delivery: prolapse = 1.82 (95% CI 1.04-3.19), stress urinary incontinence = 1.81 (95% CI 1.25-2.61), overactive bladder = 1.53 (95% CI 1.02-2.29), anal incontinence = 1.72 (95% CI 1.27-2.35), and any one or more pelvic floor disorders = 1.85 (95% CI 1.42-2.41). Number-needed-to-treat analysis revealed that 7 women would have to deliver only by cesarean delivery to prevent one woman from having a pelvic floor disorder. CONCLUSION: The risk of pelvic floor disorders is independently associated with vaginal delivery but not with parity alone. Cesarean delivery has a protective effect, similar to nulliparity, on the development of pelvic floor disorders when compared with vaginal delivery. LEVEL OF EVIDENCE: II-2.     

Short-term maternal and neonatal outcomes by mode of delivery. A case-controlled study

OBJECTIVE: Side-by-side comparisons of short-term maternal and neonatal outcomes for spontaneous vaginal delivery, instrumental vaginal delivery, planned caesarean section and caesarean section during labor in patients matched for clinical condition, age, and week of gestation are lacking. This case-controlled study was undertaken to evaluate short-term maternal and neonatal complications in a healthy population at term by mode of delivery. STUDY DESIGN: Four groups of healthy women, with antenatally normal singleton pregnancies at term, who underwent instrumental vaginal delivery (no. 201), spontaneous delivery (no. 402), planned caesarean section without labor (no. 402) and caesarean section in labor (no. 402) have been retrospectively selected. Outcome measures were maternal and neonatal short-term complications. Odds ratios (OR) and 95% confidence intervals (CI) were calculated. RESULTS: Maternal complications were mostly associated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 6.9; 95% CI: 2.9-16.4 and OR 3.0; 95% CI 1.1-8.8, respectively, versus spontaneous deliveries). No significant differences in overall complications were observed between spontaneous vaginal deliveries and caesarean sections, whether planned or in labor. By comparison with caesarean sections in labor, instrumental deliveries significantly increased the risk of complications (OR: 3.2; 95% CI: 1.6-6.5). Neonatal complications were also mostly correlated with forceps-assisted and vacuum-assisted instrumental deliveries (OR: 3.5; 95% CI: 1.9-6.7 and OR 3.8; 95% CI 2.0-7.4, respectively, versus spontaneous deliveries). By comparison with caesarean sections in labor, instrumental vaginal deliveries significantly increased the risk of complications (OR: 4.2; 95% CI: 2.4-7.4). CONCLUSIONS: In healthy women with antenatally normal singleton pregnancies at term, instrumental deliveries are associated with the highest rate of short-term maternal and neonatal complications.     

Racial differences in severe perineal lacerations after vaginal delivery

OBJECTIVE: The purpose of this study was to determine the relationship between maternal race and rates of third- and fourth-degree laceration after vaginal delivery. STUDY DESIGN: An electronic audit of the medical procedures database at Thomas Jefferson University Hospital from 1983 through 2000 was completed. Univariate and multivariable models were computed with the use of logistic regression models. RESULTS: From the database, 34,048 vaginal deliveries were identified, with 3487 deliveries resulting in third- or fourth-degree laceration (10.2%). Overall severe laceration rates by race with all vaginal deliveries for patients without and with episiotomy were as follows: white, 4.3% and 15.1%; black, 2.0% and 19.3%; Asian 9.1% and 32.3%; Hispanic, 3.4% and 17.0%, respectively. After being controled for other variables with multivariable logistic regression in all vaginal deliveries, Asian race (odds ratio, 2.04; 95% CI, 1.43-2.92), forceps (odds ratio, 3.71; 95% CI, 3.39-4.05), vacuum-assisted delivery (odds ratio, 1.86; 95% CI, 1.64-2.10), large size for gestational age (odds ratio, 1.94; 95% CI, 1.21-3.09), and episiotomy (odds ratio, 3.09; 95% CI, 2.66-3.59) were associated significantly with severe lacerations. CONCLUSION: Race is an independent risk factor for severe perineal lacerations after vaginal delivery, with Asian women at highest risk. Asian women who undergo episiotomy and operative vaginal delivery are especially at high risk for rectal sphincter injury.     

Impact of Episiotomy During Operative Vaginal Delivery on Obstetrical Anal Sphincter Injuries

ObjectiveThe purpose of this study was to describe associations between episiotomy at the time of forceps or vacuum-assisted delivery and obstetrical anal sphincter injuries (OASIS).MethodsThis population-based retrospective cohort study used delivery information from a provincial perinatal clinical database. Full-term, singleton, in-hospital, operative vaginal deliveries of vertex-presenting infants from April 1, 2006 to March 31, 2016 were identified. Odds ratios (ORs) and 95% confidence intervals (CIs) for associations between episiotomy and third- or fourth-degree lacerations were calculated in multiple logistic regression models (Canadian Task Force Classification II-2).ResultsEpisiotomy was performed in 34% of 52 241 operative vaginal deliveries. OASIS occurred in 21% of forceps deliveries and 7.6% of vacuum deliveries. Episiotomy was associated with increased odds of severe perineal lacerations for vacuum deliveries among women with (OR 2.48; 95% CI 1.96–3.13) and without (OR 1.12; 95% CI 1.02–1.22) a prior vaginal delivery. Among forceps deliveries, episiotomy was associated with increased odds of OASIS for those with a previous vaginal delivery (OR 1.52; 95% CI 1.12–2.06), but it was protective for women with no previous vaginal delivery (OR 0.73; 95% CI 0.67–0.79). Midline compared with mediolateral episiotomy increased the odds of OASIS in forceps deliveries (OR 2.73; 95% CI 2.37–3.13) and vacuum deliveries (OR 1.94; 95% CI 1.65–2.28).ConclusionIn conclusion, results suggest that episiotomy should be used with caution, particularly among women with a previous vaginal delivery and in the setting of vacuum-assisted delivery. Episiotomy may protect against OASIS in forceps-assisted deliveries for women without a prior vaginal delivery.     

Incidence and determinants of peripartum hysterectomy

OBJECTIVE: Most studies of peripartum hysterectomy are conducted in single institutions, limiting the ability to provide national incidence estimates and examine risk factors. The objective of this study was to provide a national estimate of the incidence of peripartum hysterectomy and to examine factors associated with the procedure. METHODS: We used data for 1998-2003 from the Healthcare Cost and Utilization Project Nationwide Inpatient Sample, an annual nationally representative survey of inpatient hospitalizations. Peripartum hysterectomy was defined as a hysterectomy and delivery occurring during the same hospitalization. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for maternal and hospital characteristics using logistic regression. RESULTS: During 1998-2003, an estimated 18,339 peripartum hysterectomies occurred in the United States (0.77 per 1,000 deliveries). Compared with vaginal delivery without a previous cesarean delivery, the ORs of peripartum hysterectomy for other delivery types were as follows: repeat cesarean, 8.90 (95% CI 8.09-9.79); primary cesarean, 6.54 (95% CI 5.95-7.18); and vaginal birth after cesarean, 2.70 (95% CI 2.23-3.26). Multiple births were associated with an increased risk compared with singleton births (OR 1.41, 95% CI 1.16-1.71). CONCLUSION: Our results suggest that vaginal birth after cesarean, primary and repeat cesarean deliveries, and multiple births are independently associated with an increased risk for peripartum hysterectomy. These findings may be of concern, given the increasing rate of both cesarean deliveries and multiple births in the United States. LEVEL OF EVIDENCE: III.     

Serious maternal morbidity after childbirth: prolonged hospital stays and readmissions

OBJECTIVE: To determine the frequency of and risk factors for serious morbidity resulting in a prolonged hospital stay or readmission among women enrolled in Tennessee's Medicaid program who delivered live or dead infants in 1991. METHODS: This retrospective cohort study included 33,251 women of white or black ethnicity. Main outcome measures included childbirth-related medical conditions serious enough to result in death, prolonged delivery hospitalization, or readmission within 60 days of delivery. RESULTS: Among 25,810 women with vaginal (78%) and 7441 (22%) women with cesarean deliveries, 2.6% and 8.9%, respectively, had at least one childbirth-related medical condition requiring prolonged delivery hospitalization or readmission, including infection (1.8% and 7.9%), hypertension-related complications (0.7% and 2.0%), or hemorrhage (0.5% and 2.4%). After controlling for other risk factors, maternal age over 32 years was independently associated with increased rate of serious morbidity among women who had vaginal (relative risk [RR] 1.9, 95% confidence interval [CI] 1.4, 2.7) or cesarean deliveries (RR 1.6, 95% CI 1.1, 2.2). Black women had approximately twice the rate of maternal morbidity with vaginal (RR 1.9, 95% CI 1.5, 2.4) or cesarean deliveries (RR 2.3, 95% CI 1.9, 2.9). Primiparous women who had vaginal or cesarean deliveries had a 60% (RR 1.6, 95% CI 1.3, 2.0) and 70% (RR 1.7, 95% CI 1.4, 2.0), respectively, greater risk of serious maternal morbidity than women with 1-3 prior births. CONCLUSION: Predictors of serious maternal morbidity included age over 32 years, black ethnicity, and primiparity.     

Risk of maternal postpartum readmission associated with mode of delivery

OBJECTIVE: To determine whether cesarean and operative vaginal deliveries are associated with an increased risk of maternal rehospitalization compared with spontaneous vaginal delivery. METHODS: A population-based cohort study was conducted by using the Canadian Institute for Health Information's Discharge Abstract Database between 1997/1998 and 2000/2001, which included 900,108 women aged 15-44 years with singleton live births (after excluding several selected obstetric conditions). RESULTS: A total of 16,404 women (1.8%) were rehospitalized within 60 days after initial discharge. Compared with spontaneous vaginal delivery (rate 1.5%), cesarean delivery was associated with a significantly increased risk of postpartum readmission (rate 2.7%, odds ratio [OR] 1.9, 95% confidence interval [CI] 1.8-1.9); ie, there was 1 excess postpartum readmission per 75 cesarean deliveries. Diagnoses associated with significantly increased risks of readmission after cesarean delivery (compared with spontaneous vaginal delivery) included pelvic injury/wounds (rate 0.86% versus 0.06%, OR 13.4, 95% CI 12.0-15.0), obstetric complications (rate 0.23% versus 0.08%, OR 3.0, 95% CI 2.6-3.5), venous disorders and thromboembolism (rate 0.07% versus 0.03%, OR 2.7, 95% CI 2.1-3.4), and major puerperal infection (rate 0.45% versus 0.27%, OR 1.8, 95% CI 1.6-1.9). Women delivered by forceps or vacuum were also at an increased risk of readmission (rates 2.2% and 1.8% versus 1.5%; OR forceps: 1.4, 95% CI 1.3-1.5; OR vacuum: 1.2, 95% CI 1.2-1.3, respectively). Higher readmission rates after operative vaginal delivery were due to pelvic injury/wounds, genitourinary conditions, obstetric complications, postpartum hemorrhage, and major puerperal infection. CONCLUSION: Compared with spontaneous vaginal delivery, cesarean delivery, and operative vaginal delivery increase the risk of maternal postpartum readmission. LEVEL OF EVIDENCE: II-2.     

Urinary incontinence in nulliparous women and their parous sisters

OBJECTIVE: To investigate the role of vaginal delivery and familial factors in the development of urinary incontinence by comparing the prevalence of this condition in nulliparous women and their parous sisters. METHODS: A sample of 143 pairs of nulliparous/parous postmenopausal sisters completed a comprehensive questionnaire regarding symptoms of pelvic floor disorders. Of these, 101 pairs underwent clinical evaluation of urinary incontinence and genital prolapse. RESULTS: Among this sample of biological sisters, urinary incontinence was reported by 47.6% of nulliparous women and by 49.7% of parous women (P = .782). We found no difference in the severity or type of urinary incontinence between these 2 groups. There was a high concordance in continence status, however, within biological sisters. CONCLUSION: Vaginal birth does not seem to be associated with urinary incontinence in postmenopausal women. Considering the high concordance in continence status between sister pairs, and considering that the majority of parous women are continent, an underlying familial predisposition toward the development of urinary incontinence may be present.     

Urinary incontinence: prevalence and risk factors at 16 weeks of gestation

Objective To evaluate the prevalence of urinary incontinence at 16 weeks of gestation and to identify possible maternal and obstetric risk factors.
Design Cross-sectional study and cohort study.
Setting Department of Obstetrics and Gynaecology, Aarhus University Hospital, Denmark.
Population Cross-sectional study: 7795 women attending antenatal care. Cohort study: a sub-group of 1781 pregnant women with one previous delivery at our department.
Results Prevalence and maternal risk factors: the prevalence of urinary incontinence within the preceding year was 8.9% among women at 16 weeks of gestation (nulliparae, 3.9%. para 1, 13.8%, para 2+, 16.2%). Stress or mixed incontinence occurred at least weekly in 3% of all the women. After adjusting for age, parity, body mass index, smoking, previous abortions, and previous lower abdominal or urological surgery in a logistic regression model, primiparous women who had delivered vaginally had higher risk of stress or mixed urinary incontinence than nulliparous women (OR 5.7; 95% CI 3.9–8.3). Subsequent vaginal deliveries did not increase the risk significantly. Young age, body mass index > 30, and smoking were possible risk factors for developing urinary incontinence. Obstetric factors: weight of the newborn > 4000 g (OR 1.9; 95% CI 14–3.6) increased the risk of urinary incontinence; mediolateral episiotomy in combination with birthweight > 4000 g also increased the risk (OR 3–5; 95% CI 1.2–10.2); a number of other intrapartum factors did not increase the risk of urinary incontinence.
Conclusions The first vaginal delivery was a major risk factor for developing urinary incontinence; subsequent vaginal deliveries did not increase the risk significantly. Birthweight > 4000 g increased the risk; episiotomy in combination with birthweight > 4000 g also increased the risk.     

Natural history of pelvic organ prolapse in postmenopausal women

OBJECTIVE: To describe the natural history of pelvic organ prolapse and risk factors for changes in vaginal descent in older women. METHODS: This 4-year prospective observational study included 259 postmenopausal women with a uterus enrolled at one Women's Health Initiative clinical site who completed at least two annual pelvic organ prolapse quantification (POP-Q) examinations. We calculated 1-year and 3-year incidence and resolution risks for prolapse (defined as maximal vaginal descent to or beyond the hymen) and estimated progression and regression rates (1 cm or greater and 2 cm or greater changes in maximal vaginal descent) and risk factors. RESULTS: Mean age was 68.1+/-5.5 years, and median vaginal parity was 4. Seventy-three (28%) women had four exams, 128 (49%) had three exams, and 58 (22%) had two exams. Prolapse waxed and waned yearly in individual women. Overall 1-year and 3-year prolapse incidences were 26% (95% confidence interval [CI] 20-33%) and 40% (95% CI 26-56%); 1-year and 3-year prolapse resolution risks were 21% (95% CI 11-33%) and 19% (95% CI 7-39%). Rates of any change in maximal vaginal descent over time varied depending on baseline measurements. Over 3 years, the maximal vaginal descent increased by at least 2 cm in 11.0% (95% CI 4.9-20.5%) of the women and decreased by at least 2 cm in 2.7% (95% CI 0.3-9.5%). Increasing body mass index and grand multiparity increased the risk for vaginal descent progression. CONCLUSION: Prolapse progresses and regresses in older women, although rates of vaginal descent progression are slightly greater than regression overall. Obesity is a risk factor for progression in vaginal descent. LEVEL OF EVIDENCE: III.     

Mode of delivery and fecal incontinence at midlife: a study of 2,640 women in the Gazel cohort

OBJECTIVE: To estimate obstetric risk factors of fecal incontinence among middle-aged women. METHODS: We conducted a mail survey of the Gazel cohort of volunteers for epidemiologic research. In 2000, a questionnaire on anal incontinence was mailed to 3,114 women who were then between the ages of 50 and 61 years; 2,640 (85%) women returned the completed questionnaire. Fecal incontinence was defined by involuntary loss of stool. Logistic regression was used to estimate the effect of obstetric and general risk factors. RESULTS: Prevalence of fecal incontinence in the past 12 months was 9.5% (250). Significant risk factors for fecal incontinence were completion of high school (adjusted odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1-2.0), self-reported depression (OR 2.1, 95% CI 1.6-2.7), overweight or obesity measured by body mass index (BMI) (OR 1.5 for BMI of 25-30, 95% CI 1.1-2.0; OR 1.6 for BMI more than 30, 95% CI 1.1-2.5), surgery for urinary incontinence (OR 3.5, 95% CI 2.0-6.1), and anal surgery (OR 1.7, 95% CI 1.1-2.9). No obstetric variable (parity, mode of delivery, birth weight, episiotomy, or third-degree perineal tear) was significant. Prevalence of fecal incontinence was similar for nulliparous, primiparous, secundiparous, and multiparous women (11.3%, 9.0%, 9.0%, and 10.4%, respectively), and among parous women, it was similar for women with spontaneous vaginal, instrumental (at least one), or only cesarean deliveries (9.3%, 10.0%, and 6.6%, respectively). CONCLUSION: In our population of women in their 50s, fecal incontinence was not associated with either parity or mode of delivery.     

The effect of sequential use of vacuum and forceps for assisted vaginal delivery on neonatal and maternal outcomes

OBJECTIVE: To determine the risk of neonatal and maternal disease associated with the sequential use of vacuum and forceps compared with spontaneous vaginal delivery. STUDY DESIGN: Using Washington state birth certificate data linked to hospital discharge records, we compared 3741 vaginal deliveries by both vacuum and forceps, 3741 vacuum deliveries, and 3741 forceps deliveries to 11,223 spontaneous vaginal deliveries. RESULTS: Compared with spontaneous vaginal deliveries, deliveries by sequential use of vacuum and forceps had significantly higher rates of intracranial hemorrhage (relative risk [RR], 3.9; 95% confidence interval [CI], 1.5 to 10.1), brachial plexus (RR, 3.2; 95% CI, 1.6 to 6.4), facial nerve injury (RR, 13.3; 95% CI, 4.7 to 37.7), seizure (RR, 13.7; 95% CI, 2.1 to 88.0), depressed 5-minute Apgar score (RR, 3.0; 95% CI, 2.2 to 4.0), assisted ventilation (RR, 4.8; 95% CI, 2.1 to 11.0), fourth-degree (RR, 11.4; 95% CI, 6.4 to 20.1 among multiparous women) and other lacerations, hematoma (RR, 6.2; 95% CI, 2.1 to 18.1 among multiparous women), and postpartum hemorrhage (RR, 1.6; 95% CI, 1.3 to 2.0). The relative risk of sequential vacuum and forceps use was greater than the sum of the individual relative risks of each instrument for intracranial hemorrhage, facial nerve injury, seizure, hematoma, and perineal and vaginal lacerations. CONCLUSION: Sequential use of vacuum and forceps is associated with increased risk of both neonatal and maternal injury.     

Cesarean delivery and subsequent pregnancies

OBJECTIVE: To assess possible effects of a cesarean delivery on outcome in subsequent pregnancies. METHODS: Using an historical cohort design, we analyzed 637,497 first and second births among women with two or more single births and 242,812 first, second, and third births among women with three or more single births registered in the population-based Medical Birth Registry of Norway between 1967 and 2003. RESULTS: Compared with a vaginal delivery at first birth, a cesarean delivery at first birth was followed, in a second pregnancy, by increased risks of preeclampsia (odds ratio [OR] 2.9 and corresponding 95% confidence interval [CI] 2.8-3.1), small for gestational age (OR 1.5; CI 1.4-1.5), placenta previa (OR 1.5; CI 1.3-1.8, placenta accreta (OR 1.9; CI 1.3-2.8), placental abruption (OR 2.0; CI 1.8-2.2), and uterine rupture (OR 37.4; CI 24.9-56.2). After excluding women with the actual complication at first birth, the corresponding ORs were, in general, lower: 1.7 (CI 1.6-1.8), 1.3 (CI 1.3-1.4), 1.4 (CI 1.2-1.7), 1.9 (CI 1.3-2.8), 1.7 (CI 1.6-1.9), and 37.2 (CI 24.7-55.9), respectively. Corresponding reduction in numbers of cesarean deliveries needed to prevent one case were 114, 56, 1,140, 3,706, 300, and 461. In third births, ORs after repeat cesarean delivery were similar to or lower than the ORs after one cesarean delivery; also here, the exclusion of women with the actual outcome in any of their previous pregnancies tended to reduce the ORs. CONCLUSION: Cesarean delivery was associated with an increased risk of complications in a subsequent pregnancy, but excess risks were reduced after excluding women with the actual complication in any of their previous births. To obtain less biased effects of cesarean delivery on subsequent pregnancies, it is important to account for obstetric history. LEVEL OF EVIDENCE: II.     

Cohort study of maternal and neonatal morbidity in relation to use of episiotomy at instrumental vaginal delivery

OBJECTIVE: The aim of this study was to investigate the maternal and neonatal morbidity related to use of episiotomy for vacuum and forceps deliveries. DESIGN: Retrospective population-based cohort study. SETTING: Dundee, Scotland. POPULATION: Two thousand one hundred and fifty three women who experienced an instrumental vaginal delivery between January 1998 and December 2002. METHODS: Univariate and multivariate logistic regression analyses were performed comparing deliveries with and without the use of episiotomy. MAIN OUTCOME MEASURES: Extensive perineal tears (third and fourth degree) and shoulder dystocia. RESULTS: Two hundred and forty-one (11%) of the 2153 women who underwent instrumental vaginal deliveries did not receive an episiotomy. Vacuum delivery was associated with less use of episiotomy compared with forceps (odds ratio 0.10, 95% CI 0.07-0.14). Extensive perineal tears were more likely with use of episiotomy (7.5%vs 2.5%, adjusted OR 2.92, 95% CI 1.27-6.72) as was neonatal trauma (6.0%vs 1.7%, adjusted OR 2.62, 95% CI 1.05-6.54). Use of episiotomy did not reduce the risk of shoulder dystocia (6.9%vs 4.6%, adjusted OR 1.43, 95% CI 0.74-2.76). The findings were similar for delivery by vacuum and forceps. CONCLUSION: The use of episiotomy increased the risk of extensive perineal tears without a reduction in the risk of shoulder dystocia.     

Is meconium passage a risk factor for maternal infection in term pregnancies?

OBJECTIVE:To study the association between meconium and maternal infection. METHODS:This was a retrospective cohort study of 678 pregnant women. All term deliveries during a 31-month period with meconium passage were included. Each meconium delivery was matched with a consecutive delivery without meconium at the same gestational age. RESULTS: The overall infection rate was 16%, with 13% of the infections directly related to the pregnancy, labor, and delivery. The endometritis rate was 5%, with 7.1% and 3% in the meconium and no-meconium group, respectively. The chorioamnionitis rate was 8.3%, with 9.5% in the meconium and 7.1% in the no-meconium group. Factors found to be associated with overall obstetric infections had the following odds ratios (ORs) and 95% confidence intervals (CIs): meconium (OR 1.8, 95% CI 1.1, 2.8), internal monitoring (OR 3.4, 95% CI 1.9, 5.9), amnioinfusion (OR 2.0, 95% CI 1.3, 3.3), number of vaginal exams (OR 4.5, 95% CI 2.8, 7.1), length of labor (OR 2.8, 95% CI 1.8, 4.4), and cesarean (OR 3.1, 95% CI 1.9, 5.1). Logistic regression analyses revealed the following ORs and 95% CIs: 1) for endometritis-cesarean (OR 4.2, 95% CI 1.9, 8.9), internal monitoring (OR 2.5, 95% CI 1.1, 5.9), and meconium (OR 2.5, 95% CI 1.1, 5.5), and 2) for chorioamnionitis-length of labor greater than 10 hours (OR 2.7, 95% CI 1.4, 5.6), number of vaginal exams greater than seven (OR 3.4, 95% CI 1.7, 6.6), and use of internal monitors (OR 2.5, 95% CI 1.2, 5.3). CONCLUSION: Meconium passage increases the risk of postpartum endometritis but not chorioamnionitis. Length of labor, internal monitoring, and number of vaginal exams are risk factors for chorioamnionitis.     

Detection of cesarean scars by transvaginal ultrasound

OBJECTIVE: To assess the ability of transvaginal ultrasound to detect cesarean scars and their defects in the nonpregnant state. METHODS: Asymptomatic, parous volunteers underwent transvaginal ultrasound of the cervix, uterus, and adnexa. Uterine measurements, the presence or absence of a cesarean scar, and the presence of a scar defect, defined as fluid within the scar, were recorded. All subjects completed a self-report questionnaire regarding obstetric history. Sonographers and investigators were blinded to subject history. RESULTS: A total of 70 subjects were enrolled. Of these, 38 women had a prior vaginal delivery and 32 women a prior cesarean delivery. One woman with a bicornuate uterus and three cesarean deliveries was excluded from data analysis. Real-time transvaginal ultrasound proved 100% sensitive (exact 95% confidence interval [CI] 88.8, 100) and 100% specific (exact 95% CI 90.7, 100). Stored image review had a sensitivity of 87% (exact 95% CI 70.2, 96.4) and a specificity of 100% (exact 95% CI 90.7, 100). Fluid was visualized within the scars of 13 of 31 subjects (42%) with a prior cesarean delivery. All 13 were found among the 23 subjects (56%) who had labored prior to cesarean delivery. Moreover, women with cesarean scar defects had a greater number of cesarean deliveries (P <.04) than women without scar defects. CONCLUSIONS: Transvaginal ultrasound is highly accurate in detecting cesarean hysterotomy scars. Cesarean scar defect, defined by the presence of fluid within the incision site, was more common when labor preceded cesarean delivery and with multiple cesarean deliveries.     

Obstetric anal sphincter lacerations

OBJECTIVE: To estimate the frequency of obstetric anal sphincter laceration and to identify characteristics associated with this complication, including modifiable risk factors. METHODS: A population-based, retrospective study of over 2 million vaginal deliveries at California hospitals was performed, using information from birth certificates and discharge summaries for 1992 through 1997. We excluded preterm births, stillbirths, breech deliveries, and multiple gestations. The main outcome measure was obstetric anal sphincter laceration (third and fourth degree). RESULTS: The frequency of anal sphincter lacerations was 5.85% (95% confidence interval [CI] 5.82, 5.88), decreasing significantly from 6.35% (95% CI 6.27, 6.43) in 1992 to 5.43% (95% CI 5.35, 5.51) in 1997 (P <.01). Using logistic regression analysis, we identified primiparity as the dominant risk factor (odds ratio [OR] for women with prior vaginal birth 0.15; 95% CI 0.14, 0.15). Birth weight over 4000 g was also highly significant (OR 2.17; 95% CI 2.07, 2.27). Lacerations occurred more often among women of certain racial and ethnic groups: Indian women (OR 2.5; 95% CI 2.23, 2.79) and Filipina women (OR 1.63; 95% CI 1.50, 1.77) were at highest risk. Episiotomy decreased the likelihood of third-degree lacerations (OR 0.81; 95% CI 0.78, 0.85), but increased the risk of fourth-degree lacerations (OR 1.12; 95% CI 1.05, 1.19). Operative delivery increased the risk of sphincter laceration, with vacuum delivery (OR 2.30; 95% CI 2.21, 2.40) presenting a greater risk than forceps delivery (OR 1.45; 95% CI 1.37, 1.52). CONCLUSION: Anal sphincter lacerations are strongly associated with primiparity, macrosomia, and operative vaginal delivery. Of the modifiable risk factors, operative vaginal delivery remains the dominant independent variable.     

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.