Biomedical subjects

Michael W Varner

Publications and source records attributed to Michael W Varner.

At least 37 records · Page 2Linked to original sources

PubMed2005

The Maternal-Fetal Medicine Unit cesarean registry: trial of labor with a twin gestation.

OBJECTIVE: The purpose of this study was to identify the success rates and risks in women with a twin pregnancy who attempt a trial of labor after cesarean delivery. STUDY DESIGN: Cases were identified in the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network's Cesarean Registry with a woman with a twin pregnancy who had had at least 1 previous cesarean delivery. RESULTS: During the study period (1999-2002), 412 women fulfilled the study criteria, and 226 women had elective repeat cesarean delivery. Of the 186 women (45.1% of total) who attempted a trial of labor, 120 women were delivered successfully (success rate, 64.5%), and 66 women (35.5%) had a failed trial of labor. Thirty of the failed trials of labor involved a vaginal delivery for twin A and cesarean delivery for twin B. Women who attempted a trial of labor with twins had no increased risk of transfusion, endometritis, intensive care unit admissions, or uterine rupture when compared with elective repeat cesarean delivery. Fetal and neonatal complications were uncommon in either group at>or=34 weeks of gestation. CONCLUSION: A trial of labor with twins after previous cesarean delivery does not appear to increase maternal morbidity. Perinatal morbidity is uncommon at>or=34 weeks of gestation.

Adult↗

PubMed2005

The MFMU Cesarean Registry: factors affecting the success of trial of labor after previous cesarean delivery.

OBJECTIVE: The purpose of this study was to determine which factors influence the likelihood of successful trial of labor (TOL) after 1 previous cesarean delivery (CD). STUDY DESIGN: We performed a multicenter 4-year prospective observational study (1999-2002) of all women with previous CD undergoing TOL. Women with term singleton pregnancies with 1 previous low transverse CD or unknown incision were included for analysis. RESULTS: Fourteen thousand five hundred twenty-nine women underwent TOL, with 10,690 (73.6%) achieving successful VBAC. Women with previous vaginal birth had an 86.6% success rate compared with 60.9% in women without such a history (odds ratio [OR] 4.2; 95% CI 3.8-4.5; P < .001). TOL success rates were affected by previous indication for CD, need for induction or augmentation, cervical dilation on admission, birth weight, race, and maternal body mass index. Multivariate logistic regression analysis identified as predictive of TOL success: previous vaginal delivery (OR 3.9; 95% CI 3.6-4.3), previous indication not being dystocia (CPD/FTP) (OR 1.7; 95% CI 1.5-1.8), spontaneous labor (OR 1.6; 95% CI 1.5-1.8), birth weight <4000 g (OR 2.0; 95% CI 1.8-2.3), and Caucasian race (OR 1.8, 95% CI 1.6-1.9) (all P < .001). The overall TOL success rate in obese women (BMI > or = 30) was lower (68.4%) than in nonobese women (79.6%) (P < .001), and when combined with induction and lack of previous vaginal delivery, successful VBAC occurred in only 44.2% of cases. CONCLUSION: Previous vaginal delivery including previous VBAC is the greatest predictor for successful TOL. Previous indication as dystocia, need for labor induction, or a maternal BMI > or = 30 significantly lowers success rates.

Adult↗

PubMed2005

Progesterone for prevention of recurrent preterm birth: impact of gestational age at previous delivery.

OBJECTIVE: Preterm birth occurs in 1 of 8 pregnancies and may result in significant morbidity and mortality. 17-alpha hydroxyprogesterone caproate (17-OHP caproate) has been found to be efficacious in reducing the risk of subsequent preterm delivery in women who have had a previous spontaneous preterm birth (sPTB). This analysis was undertaken to evaluate if 17-OHP caproate therapy works preferentially depending on the gestational age at previous spontaneous delivery. We hypothesized that treatment with 17-OHP caproate is more effective in prolonging pregnancy depending on the gestational age of the earliest previous preterm birth (20-27.9, 28-33.9 vs 34-36.9 weeks). STUDY DESIGN: This was a secondary analysis of 459 women with a previous sPTB enrolled in a randomized controlled trial evaluating 17-OHP caproate versus placebo. Effectiveness of 17-OHP caproate for pregnancy prolongation was evaluated based on gestational age at earliest previous delivery according to clinically relevant groupings (20-27.9, 28-33.9, and 34-36.9 weeks). Statistical analysis included the chi-square, Fisher exact, and Kruskal-Wallis tests, logistic regression, and survival analysis using proportional hazards. RESULTS: Gestational age at earliest previous delivery was similar between women treated with 17-OHP caproate or placebo (P = .1). Women with earliest delivery at 20 to 27.9 weeks and at 28 to 33.9 weeks delivered at significantly more advanced gestational age if treated with 17-OHP caproate than with placebo (median 37.3 vs 35.4 weeks, P = .046 and 38.0 vs 36.7 weeks, P = .004, respectively) and were less likely to deliver <37 weeks (42% vs 63%, P = .026 and 34% vs 56%, P = .005, respectively). Those with earliest delivery at 34 to 36.9 weeks were not significantly different between 17-OHP caproate or control. CONCLUSION: 17-OHP caproate therapy given to prevent recurrent PTB is associated with a prolongation of pregnancy overall, and especially for women with a previous spontaneous PTB at <34 weeks.

17-alpha-Hydroxyprogesterone↗

PubMed2005

Plasma CRH measurement at 16 to 20 weeks' gestation does not predict preterm delivery in women at high-risk for preterm delivery.

OBJECTIVE: The purpose of this study was to examine the utility of a single second-trimester plasma corticotropin-releasing hormone measurement as a marker for preterm delivery in women at high risk for preterm delivery. STUDY DESIGN: This is an analysis of data from a multicenter placebo-controlled trial designed to evaluate the role of 17 alpha hydroxyprogesterone caproate (17P) in the prevention of recurrent preterm birth. Women with a documented history of a previous spontaneous preterm birth at <37 weeks were enrolled (16-20 wks) and randomly assigned in a 2 to 1 ratio to weekly injections of 17P or matching placebo. Blood was collected before treatment in 170 patients (113 assigned 17P and 57 placebo) who were enrolled at 11 of the 19 centers. Plasma levels of corticotropin-releasing hormone were compared between those who delivered preterm and those delivering at term. Data were analyzed using the Wilcoxon rank-sum test. RESULTS: The overall rates of preterm birth in this cohort of 170 patients were 35.9% at <37 weeks (31.9% progesterone, 43.9% placebo), and 19.4% at <35 weeks (18.6% vs 21.1%). The median levels of corticotropin-releasing hormone were similar between those delivering at <37 weeks and those delivering > or = 37 weeks (0.39 ng/mL vs 0.37 ng/mL, P = .08). In addition, there were no differences in corticotropin-releasing hormone levels among those who delivered at <35 weeks or > or = 35 weeks (0.36 vs 0.38, P = .90). Moreover, there were no differences in corticotropin-releasing hormone levels among those in the placebo group who delivered at <37 or > or = 37 weeks (0.40 vs 0.41, P = .72) and at <35 or > or = 35 weeks (P = .64). CONCLUSION: A single measurement of corticotropin-releasing hormone at 16 to 20 weeks' gestation is not a good biomarker for recurrent preterm delivery in patients at high risk for this complication.

Adult↗

PubMed2005

The MFMU Cesarean Registry: uterine atony after primary cesarean delivery.

OBJECTIVE: The purpose of this study was to define independent risk factors for uterine atony after primary cesarean delivery, and to assess their overall association with atony in the study cohort. STUDY DESIGN: This was a 13-university center prospective observational study. All women who underwent primary cesarean from January 1, 1999 to December 31, 2000 were eligible. Trained and certified research nurses performed systematic data abstraction. The definition of atony required both the clinical diagnosis and the use of methergine or a prostaglandin preparation. Risk factors for uterine atony were assessed in univariable and multivariable logistic regression analyses, and these analyses then used to inform an assessment of the association of the various risk factors with the occurrence of uterine atony in the overall cohort. RESULTS: Twenty-three thousand, three hundred and ninety pregnancies were analyzed. Uterine atony occurred in 1416 women (6%). Several variables were independently associated with atony in a multivariable model, including multiple gestation (odds ratio [OR] 2.40, 95% CI 1.95-2.93), maternal Hispanic race (2.21, 1.90-2.57), induced or augmented labor for >18 hours (2.23, 1.92-2.60), infant birth weight >4500 g (2.05, 1.53-2.69), and clinically diagnosed chorioamnionitis (1.80, 1.55-2.09). However, because the various risk factors were not very powerful, approximately half of the cases of atony were associated with the 2/3 of women lacking a given risk factor or combination of risk factors. CONCLUSION: Although certain risk factors and uterine atony were clearly associated, the associations are of limited practical clinical use.

Adult↗

PubMed2005

Is there a seasonal variation in the diagnosis of oligohydramnios?

OBJECTIVE: We hypothesized that oligohydramnios would be diagnosed more frequently in the warm summer months when dehydration might be more common. METHODS: The clinical diagnosis of oligohydramnios was extracted from the databases of four completed National Institute of Child Health and Human Development Maternal Fetal Medicine Units Network protocols. These data were stratified by quarter of delivery and compared using Fisher's Exact Test. RESULTS: The clinical diagnosis of oligohydramnios was made more frequently in deliveries occurring in the summer months of June, July and August as compared with the remainder of the calendar year (7.2% vs 5.9%, p=0.0178). CONCLUSIONS: In these studies the diagnosis of oligohydramnios is made more frequently in those pregnancies delivered during the summer months. Although not proven by this association, maternal dehydration may contribute to this finding.

Adolescent↗

PubMed2005

Spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy.

OBJECTIVE: We sought to estimate the rate of spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy and to evaluate factors associated with its resolution. METHODS: A cohort of women enrolled in a large multicenter randomized bacterial vaginosis antibiotic trial (metronidazole versus placebo) that, when randomly allocated, had asymptomatic C trachomatis diagnosed by urine ligase chain reaction (from frozen archival specimens) between 16(0/7) and 23(6/7) weeks were included. The urine ligase chain reaction is a highly accurate predictor of genital tract chlamydial infection. A follow-up ligase chain reaction was performed between 24(0/7) and 29(6/7) weeks. RESULTS: A total of 1,953 women were enrolled in the original antibiotic trial; 1,547 (79%) had ligase chain reaction performed both at randomization and follow-up. Women receiving antibiotics effective against Chlamydia between randomization and follow-up or having symptomatic Chlamydia infection were excluded (26 women). Of the 140 women (9%) who were diagnosed as positive via the initial ligase chain reaction assay, 61 (44%) had spontaneous resolution of Chlamydia by the follow-up ligase chain reaction assay. Factors associated with spontaneous resolution included older age (P = .02), more than 5 weeks from randomization to follow-up (P = .02), and a greater number of lifetime sexual partners (P = .02). Using a logistic regression model, maternal age and a greater-than-5-week follow-up interval remained significant; for every 5-year increase in maternal age, the odds of a positive result on the ligase chain reaction test at follow-up decreased by 40% (odds ratio 0.6; 95% confidence interval 0.4-0.9). Race, substance abuse, parity, and treatment with metronidazole were not associated with spontaneous resolution. Gram stain score and vaginal pH at randomization and follow-up also were not associated. CONCLUSION: The prevalence of asymptomatic C trachomatis in pregnancy was 9%; infection resolved spontaneously in almost half of these women. The association of older age and increasing time interval to spontaneous resolution of Chlamydia is consistent with a host immune-response mechanism.

Adult↗

PubMed2005

Complications of anesthesia for cesarean delivery.

OBJECTIVE: To quantify anesthesia-related complications associated with cesarean delivery in a well-described, prospectively ascertained cohort from multiple university-based hospitals in the United States and to evaluate whether certain factors would identify women at increased risk for a failed regional anesthetic. METHODS: A prospective observational study was conducted of women (n = 37,142) with singleton gestations undergoing cesarean delivery in the centers forming the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Detailed information was collected regarding choice of anesthesia and procedure-related complications, including failed regional anesthetic and maternal death. Potential risk factors for a failed regional anesthetic were analyzed. RESULTS: Of the women studied, 34,615 (93%) received a regional anesthetic. Few (3.0%) regional procedures failed, and related maternal morbidity was rare. Increased maternal size, higher preoperative risk, rapid decision-to-incision interval, and placement later in labor were all significantly related to an increased risk of a failed regional procedure. Of the general anesthetics, 38% were administered when the decision-to-incision interval was less than 15 minutes. Women deemed at the greatest preoperative risk (American Society of Anesthesiologists score > or = 4) were approximately 7-fold more likely to receive a general anesthetic (odds ratio 6.9, 95% confidence interval 5.83-8.07). There was one maternal death, due to a failed intubation, in which the anesthetic procedure was directly implicated. CONCLUSION: Regional techniques have become the preferred method of anesthesia for cesarean delivery. Procedure-related complications are rare and attest to the safety of modern obstetric anesthesia for cesarean delivery in the United States.

Adolescent↗

PubMed2005

Does progesterone treatment influence risk factors for recurrent preterm delivery?

OBJECTIVE: To examine how demographic and pregnancy characteristics can affect the risk of recurrent preterm delivery and the how the effectiveness of progesterone treatment for prevention alters these relationships. METHODS: This was a secondary analysis of a randomized trial of 17alpha-hydroxyprogesterone caproate to prevent recurrent preterm delivery in women at risk. Associations of risk factors for preterm delivery (less than 37 completed weeks of gestation) were examined separately for the women in the 17alpha-hydroxyprogesterone caproate (n = 310) and placebo (n = 153) groups. RESULTS: Univariate analysis found that the number of previous preterm deliveries and whether the penultimate delivery was preterm were significant risk factors for preterm delivery in both the placebo and progesterone groups. High body mass index was protective of preterm birth in the placebo group. Multivariate analysis found progesterone treatment to cancel the risk of more than 1 previous preterm delivery, but not the risk associated with the penultimate pregnancy delivered preterm. Obesity was associated with lower risk for preterm delivery in the placebo group but not in the women treated with progesterone. CONCLUSION: The use of 17alpha-hydroxyprogesterone caproate in women with a previous preterm delivery reduces the overall risk of preterm delivery and changes the epidemiology of risk factors for recurrent preterm delivery. In particular, these data suggest that 17alpha-hydroxyprogesterone caproate reduces the risk of a history of more than 1 preterm delivery. LEVEL OF EVIDENCE: I.

17 alpha-Hydroxyprogesterone Caproate↗

PubMed2005

Effect of grand multiparity on intrapartum and newborn complications in young women.

OBJECTIVE: To examine the effect of high parity on complications in young women, aged 18-34 years. METHODS: Seven years of Utah birth certificate data were reviewed (1995-2001). Young nulliparas and primiparas were compared with young grand and great grand multi-paras by using logistic regression. Young grand multiparas were compared with older grand multiparas. RESULTS: Young grand multiparas were more likely to have a preterm delivery and less likely to experience fetal distress, instrumented delivery, cesarean delivery, and any intrapartum complication than young nulliparas or primiparas. Young grand multiparas were less likely to experience many complications than their older counterparts. CONCLUSION: Among young women, grand and great grand multiparity does not increase the risk for most intrapartum and newborn complications. Young grand and great grand multiparas are at significantly decreased risk for many complications when compared with young women of lower parity and older grand and great grand multiparas. LEVEL OF EVIDENCE: II-2.

Adult↗

PubMed2005

Current understanding of genetic factors in preterm birth.

Several lines of evidence support a genetic predisposition to spontaneous preterm labour and preterm birth. Firstly, a leading risk factor for spontaneous preterm labour and preterm birth is a personal or family history. If a woman previously delivered preterm, her subsequent babies are also more likely to be born preterm. Women who experienced an early preterm birth (<32 completed weeks) in their first pregnancy have the highest rate of recurrent preterm birth in subsequent pregnancies. Spontaneous preterm labour and preterm birth in subsequent pregnancies tend to recur at equivalent gestational ages. If a woman herself was born preterm, she is also at an increased risk of spontaneous preterm labour and preterm birth, with the risks being highest for those women who themselves were born most preterm. This predisposition does not apply to men who were born preterm. Racial predispositions to preterm birth have also been observed. Black women suffer twice the rate of preterm birth compared with Caucasians, even when confounding social and economic variables are controlled. It is well established that upper genital tract infection and/or inflammation is seen in association with spontaneous preterm labour and preterm birth. Previous investigations have focussed primarily on an infectious aetiology for this finding. However, an alternative hypothesis has emerged, which suggests that this finding may represent an abnormal inflammatory response. The frequent association of spontaneous preterm labour and preterm birth with histological infection/inflammation and elevated body fluid concentrations of inflammatory cytokines has focussed investigations on single gene polymorphisms of these cytokines in both mother and fetus. The polymorphisms tumour necrosis factor-alpha-308 (TNF-alpha-308), interleukin-1beta (IL-1beta) + 3953/3954 and IL-6-174 have been most consistently associated with spontaneous preterm labour and preterm birth. Toll-like receptors (TLRs) are important components of the innate immune systems, which have also been linked to spontaneous preterm labour and preterm birth. Both maternal and fetal polymorphisms of the TLR-4 gene have been associated with spontaneous preterm labour and preterm birth in certain populations, but in others no apparent link has been observed. These findings confirm a clear genetic predisposition to spontaneous preterm labour and preterm birth and raise hopes that patient-specific therapies may be developed in the future.

Cytokines↗

PubMed2005

Genetic factors in preterm birth--the future.

The genetic regulation of common biological functions has redundant control mechanisms, and it is unlikely that a single marker will ever be identified that will be both highly sensitive and specific. It is more likely that combinations of gene and/or protein markers, perhaps also combined with obstetric family histories, will be required to achieve the goal of a truly sensitive and specific screening profile for spontaneous preterm labour and preterm birth. The rapidly evolving disciplines of genomics and proteomics are now beginning to be applied to the study of spontaneous preterm labour and preterm birth. These techniques are able to measure multiple markers (in the thousands) in a biological sample and, given the likely presence of biological changes that precede by weeks or even months the clinical manifestations of the disease, are ideally suited to the evaluation of spontaneous preterm labour and preterm birth. Over the next few years, these technologies will hasten a deeper understanding of the pathophysiology of spontaneous preterm labour, discover novel target molecules and diagnostic biomarkers and ultimately aid in formulating more effective interventions to prevent preterm birth. Pharmacogenomics is another rapidly evolving discipline that holds great promise for the treatment and prevention of spontaneous preterm labour and preterm birth. Because spontaneous preterm labour is a final common pathway for multiple aetiologies, there remains no reason why any single therapy will work optimally for all women. As patient-specific pharmacogenomic profiles are developed, it will be possible to develop patient-specific treatment regimens. Beyond that, it may become possible to identify those women who are, or are not, destined to labour spontaneously and give birth remote from term and to institute patient-specific preventive measures. Spontaneous preterm labour and preterm birth remains a syndrome, with a final common pathway for multiple aetiologies. As a result, no single explanation, marker or treatment is likely to be 100% sensitive, specific or successful. It is also clear, however, that there is a genetic predisposition in many cases of spontaneous preterm labour. Over the next few years, several recently developed diagnostic mechanisms, and others that have yet to evolve, will hold a greater potential than ever before to unlock the secrets of the genetic predisposition to spontaneous preterm labour and its underlying causes. An improved understanding of these mechanisms will allow clinicians to employ therapies that will be optimally effective for individual women and their unborn babies. Eventually, these advances could be applied to the presymptomatic prevention of spontaneous preterm labour. It is the intent of this manuscript to review the current status of these new technologies and disciplines and to speculate on their applications in the intermediate future.

Biomedical Research↗

PubMed2004

Maternal and perinatal outcomes associated with a trial of labor after prior cesarean delivery.

BACKGROUND: The proportion of women who attempt vaginal delivery after prior cesarean delivery has decreased largely because of concern about safety. The absolute and relative risks associated with a trial of labor in women with a history of cesarean delivery, as compared with elective repeated cesarean delivery without labor, are uncertain. METHODS: We conducted a prospective four-year observational study of all women with a singleton gestation and a prior cesarean delivery at 19 academic medical centers. Maternal and perinatal outcomes were compared between women who underwent a trial of labor and women who had an elective repeated cesarean delivery without labor. RESULTS: Vaginal delivery was attempted by 17,898 women, and 15,801 women underwent elective repeated cesarean delivery without labor. Symptomatic uterine rupture occurred in 124 women who underwent a trial of labor (0.7 percent). Hypoxic-ischemic encephalopathy occurred in no infants whose mothers underwent elective repeated cesarean delivery and in 12 infants born at term whose mothers underwent a trial of labor (P<0.001). Seven of these cases of hypoxic-ischemic encephalopathy followed uterine rupture (absolute risk, 0.46 per 1000 women at term undergoing a trial of labor), including two neonatal deaths. The rate of endometritis was higher in women undergoing a trial of labor than in women undergoing repeated elective cesarean delivery (2.9 percent vs. 1.8 percent), as was the rate of blood transfusion (1.7 percent vs. 1.0 percent). The frequency of hysterectomy and of maternal death did not differ significantly between groups (0.2 percent vs. 0.3 percent, and 0.02 percent vs. 0.04 percent, respectively). CONCLUSIONS: A trial of labor after prior cesarean delivery is associated with a greater perinatal risk than is elective repeated cesarean delivery without labor, although absolute risks are low. This information is relevant for counseling women about their choices after a cesarean section.

Adolescent↗

PubMed2004

Randomized trial of inhaled beclomethasone dipropionate versus theophylline for moderate asthma during pregnancy.

OBJECTIVE: This study was undertaken to compare the efficacy of inhaled beclomethasone dipropionate to oral theophylline for the prevention of asthma exacerbation(s) requiring medical intervention. STUDY DESIGN: A prospective, double-blind, double placebo-controlled randomized clinical trial of pregnant women with moderate asthma was performed. RESULTS: There was no significant difference (P=.554) in the proportion of asthma exacerbations among the 194 women in the beclomethasone cohort (18.0%) versus the 191 in the theophylline cohort (20.4%; risk ratio [RR]=0.9, 95% CI=0.6-1.3). The beclomethasone cohort had significantly lower incidences of discontinuing study medications caused by side effects (RR=0.3, 95% CI=0.1-0.9; P=.016), and proportion of study visits with forced expiratory volume expired in 1 second (FEV1) less than 80% predicted (0.284+/-0.331 vs 0.284+/-0.221, P=.039). There were no significant differences in treatment failure, compliance, or proportion of peak expiratory flow rate less than 80% predicted. There were no significant differences in maternal or perinatal outcomes. CONCLUSION: The treatment of moderate asthma with inhaled beclomethasone versus oral theophylline resulted in similar rates of asthma exacerbations and similar obstetric and perinatal outcomes. These results favor the use of inhaled corticosteroids for moderate asthma during pregnancy because of the improved FEV1 and because theophylline had more side effects and requires serum monitoring.

Administration, Inhalation↗

PubMed2004

The Maternal-Fetal Medicine Units cesarean registry: chorioamnionitis at term and its duration-relationship to outcomes.

OBJECTIVE: The purpose of this study was to evaluate the relationship between chorioamnionitis and its duration to adverse maternal, fetal, and neonatal outcomes. STUDY DESIGN: This was a 13-university center, prospective observational study. All women at term carrying a singleton gestation who underwent primary cesarean from January 1, 1999 to December 31, 2000 were eligible. Data abstraction was systematic and performed by trained research nurses. Selected adverse outcomes were compared between pregnancies with, and without, clinically diagnosed chorioamnionitis using relative risks (RRs) and 95% CIs. The duration of chorioamnionitis was stratified into 5 intervals ( 3-6 h,>6-9 h,>9-12 h, and>12 h), and respective outcomes compared by Mantel-Haenszel test for trend. Additionally, regression analysis was used to compute odds ratios (ORs) and 95% CIs for chorioamnionitis duration length as a continuous explanatory variable. RESULTS: 16,650 pregnancies were analyzed, 1965 (12%) with chorioamnionitis, which was associated with significantly increased risks of maternal blood transfusion, uterine atony, septic pelvic thrombophlebitis, and pelvic abscess (RR 2.3-3.7), as well as 5-minute Apgar <or=3, neonatal sepsis, and seizures (RR 2.1-2.8). By test of trend, only uterine atony (P <.01), maternal blood transfusion (P=.03), maternal admission to intensive care unit (P=.02), and 5-minute Apgar <or=3 (P <.01) were associated with duration of chorioamnionitis. By logistic analysis, only uterine atony (OR for each hour of chorioamnionitis 1.03, 95% CI 1.00-1.06), 5-minute Apgar <or=3 (OR 1.09, 95% CI 1.00-1.16), and neonatal mechanical ventilation within 24 hours of birth (OR 1.07, 95% CI 1.01-1.12) were significantly associated with chorioamnionitis duration. CONCLUSION: Chorioamnionitis was associated with increased rates of morbidity after cesarean at term. The duration of chorioamnionitis, however, was not related to most measures of adverse maternal or fetal-neonatal outcome.

Adult↗

PubMed2004

The relationship of asthma medication use to perinatal outcomes.

BACKGROUND: Maternal asthma has been reported to increase the risk of preeclampsia, preterm deliveries, and lower-birth-weight infants, but the mechanisms of this effect are not defined. OBJECTIVE: We sought to evaluate the relationship between the use of contemporary asthma medications and adverse perinatal outcomes. METHODS: Asthmatic patients were recruited from the 16 centers of the National Institute of Child Health and Human Development Maternal Fetal Medicine Units Network from December 1994 through February 2000. Gestational medication use was determined on the basis of patient history at enrollment and at monthly visits during pregnancy. Perinatal data were obtained at postpartum chart reviews. Perinatal outcome variables included gestational hypertension, preterm births, low-birth-weight infants, small-for-gestational-age infants, and major malformations. RESULTS: The final cohort included 2123 asthmatic participants. No significant relationships were found between the use of inhaled beta-agonists (n=1828), inhaled corticosteroids (n=722), or theophylline (n=273) and adverse perinatal outcomes. After adjusting for demographic and asthma severity covariates, oral corticosteroid use was significantly associated with both preterm birth at less than 37 weeks' gestation (odds ratio, 1.54; 95% CI, 1.02-2.33) and low birth weight of less than 2500 g (odds ratio, 1.80; 95% CI, 1.13-2.88). CONCLUSIONS: Use of inhaled beta-agonists, inhaled steroids, and theophylline do not appear to increase perinatal risks in pregnant asthmatic women. The mechanism of the association between maternal oral corticosteroid use and prematurity remains to be determined.

Adolescent↗

PubMed2004

Asthma during pregnancy.

OBJECTIVE: To determine neonatal and maternal outcomes stratified by asthma severity during pregnancy by using the 1993 National Asthma Education Program Working Group on Asthma and Pregnancy definitions of asthma severity. The primary hypothesis was that moderate or severe asthmatics would have an increased incidence of delivery at <32 weeks of gestation compared with nonasthmatic controls. METHODS: This was a multicenter, prospective, observational cohort study conducted over 4 years at 16 university hospital centers. Asthma severity was defined according to the National Asthma Education Program Working Group on Asthma and Pregnancy classification and modified to include medication requirements. This study had 80% power to detect a 2- to 3-fold increase in delivery less than 32 weeks of gestation among the cohort with the moderate or severe asthma compared with controls. Secondary outcome measures included obstetrical and neonatal outcomes. RESULTS: The final analysis included 881 nonasthmatic controls, 873 with mild asthma, 814 with moderate, and 52 with severe asthma. There were no significant differences in the rates of preterm delivery less than 32 weeks (moderate or severe 3.0%, mild 3.4%, controls 3.3%; P =.873) or less than 37 weeks of gestation. There were no significant differences for neonatal outcomes except discharge diagnosis of neonatal sepsis among the mild group compared with controls, adjusted odds ratio 2.9, 95% confidence interval 1.2, 6.8. There were no significant differences for maternal complications except for an increase in overall cesarean delivery rate among the moderate-or-severe group compared with controls (adjusted odds ratio 1.4, 95% confidence interval 1.1, 1.8). CONCLUSION: Asthma was not associated with a significant increase in preterm delivery or other adverse perinatal outcomes other than a discharge diagnosis of neonatal sepsis. Cesarean delivery rate was increased among the cohort with moderate or severe asthma. LEVEL OF EVIDENCE: II-2

Adult↗

PubMed2003

Prevention of recurrent preterm delivery by 17 alpha-hydroxyprogesterone caproate.

BACKGROUND: Women who have had a spontaneous preterm delivery are at greatly increased risk for preterm delivery in subsequent pregnancies. The results of several small trials have suggested that 17 alpha-hydroxyprogesterone caproate (17P) may reduce the risk of preterm delivery. METHODS: We conducted a double-blind, placebo-controlled trial involving pregnant women with a documented history of spontaneous preterm delivery. Women were enrolled at 19 clinical centers at 16 to 20 weeks of gestation and randomly assigned by a central data center, in a 2:1 ratio, to receive either weekly injections of 250 mg of 17P or weekly injections of an inert oil placebo; injections were continued until delivery or to 36 weeks of gestation. The primary outcome was preterm delivery before 37 weeks of gestation. Analysis was performed according to the intention-to-treat principle. RESULTS: Base-line characteristics of the 310 women in the progesterone group and the 153 women in the placebo group were similar. Treatment with 17P significantly reduced the risk of delivery at less than 37 weeks of gestation (incidence, 36.3 percent in the progesterone group vs. 54.9 percent in the placebo group; relative risk, 0.66 [95 percent confidence interval, 0.54 to 0.81]), delivery at less than 35 weeks of gestation (incidence, 20.6 percent vs. 30.7 percent; relative risk, 0.67 [95 percent confidence interval, 0.48 to 0.93]), and delivery at less than 32 weeks of gestation (11.4 percent vs. 19.6 percent; relative risk, 0.58 [95 percent confidence interval, 0.37 to 0.91]). Infants of women treated with 17P had significantly lower rates of necrotizing enterocolitis, intraventricular hemorrhage, and need for supplemental oxygen. CONCLUSIONS: Weekly injections of 17P resulted in a substantial reduction in the rate of recurrent preterm delivery among women who were at particularly high risk for preterm delivery and reduced the likelihood of several complications in their infants.

17 alpha-Hydroxyprogesterone Caproate↗