Cerclage for sonographic short cervix in singleton gestations without prior spontaneous preterm birth: systematic review and meta-analysis of randomized controlled trials using individual patient-level data.

OBJECTIVE: The aim of this systematic review and meta-analysis was to quantify the efficacy of cervical cerclage in preventing preterm birth (PTB) in asymptomatic singleton pregnancies with a short mid-trimester cervical length (CL) on transvaginal sonography (TVS) and without prior spontaneous PTB. METHODS: Electronic databases were searched from inception of each database until February 2017. No language restrictions were applied. All randomized controlled trials (RCTs) of asymptomatic singleton pregnancies without prior spontaneous PTB, found to have short CL < 25 mm on mid-trimester TVS and then randomized to management with either cerclage or no cerclage, were included. Corresponding authors of all the included trials were contacted to obtain access to the data and perform a meta-analysis of individual patient-level data. Data provided by the investigators were merged into a master database constructed specifically for the review. Primary outcome was PTB < 35 weeks. Summary measures were reported as relative risk (RR) with 95% CI. The quality of the evidence was assessed using the GRADE approach. RESULTS: Five RCTs, including 419 asymptomatic singleton gestations with TVS-CL < 25 mm and without prior spontaneous PTB, were analyzed. In women who were randomized to the cerclage group compared with those in the control group, no statistically significant differences were found in PTB < 35 (21.9% vs 27.7%; RR, 0.88 (95% CI 0.63-1.23); I2 = 0%; five studies, 419 participants), < 34, < 32, < 28 and < 24 weeks, gestational age at delivery, preterm prelabor rupture of membranes (PPROM) and neonatal outcomes. In women who received cerclage compared with those who did not, planned subgroup analyses revealed a significantly lower rate of PTB < 35 weeks in women with TVS-CL < 10 mm (39.5% vs 58.0%; RR, 0.68 (95% CI, 0.47-0.98); I2 = 0%; five studies; 126 participants) and in women who received tocolytics (17.5% vs 32.7%; RR, 0.54 (95% CI, 0.31-0.93); I2 = 0%; four studies; 169 participants) or antibiotics (18.3% vs 31.5%; RR, 0.58 (95% CI, 0.33-0.98); I2 = 0%; three studies; 163 participants) as additional therapy to cerclage. The quality of evidence was downgraded two levels because of serious imprecision and indirectness, and therefore was judged as low. CONCLUSIONS: In singleton gestations without prior spontaneous PTB but with TVS-CL < 25 mm in the second trimester, cerclage does not seem to prevent preterm delivery or improve neonatal outcome. However, in these pregnancies, cerclage seems to be efficacious at lower CLs, such as < 10 mm, and when tocolytics or antibiotics are used as additional therapy, requiring further studies in these subgroups. Given the low quality of evidence, further well-designed RCTs are needed to confirm the findings of this study. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Effectiveness of cerclage according to severity of cervical length shortening: a meta-analysis.

OBJECTIVES: To estimate the effectiveness of cerclage according to degree of cervical length (CL) shortening. METHODS: A meta-analysis was carried out of trials of women with singleton gestations and second-trimester transvaginal sonographic CL < 25 mm randomized to cerclage or no cerclage. The degree of CL shortening was correlated to the efficacy of cerclage in preventing preterm birth. RESULTS: There was a significant reduction in preterm birth < 35 weeks in the cerclage compared with no cerclage groups in 208 singleton gestations with both a previous preterm birth and CL < 25 mm (relative risk, 0.61; 95% CI, 0.40-0.92). In these women, preterm birth < 37 weeks was significantly reduced with cerclage for CL < or = 5.9 mm, < or = 15.9 mm, 16-24.9 mm and < 25 mm. None of the analyses for 344 women without a previous preterm birth was significant. CONCLUSIONS: Cerclage, when performed in women with a singleton gestation, previous preterm birth and cervical length < 25 mm, seems to have a similar effect regardless of the degree of cervical shortening, including CL 16-24 mm, as well as CL < or = 5.9 mm.

The origin of endothelin-1 in patients with severe preeclampsia.

OBJECTIVE: To determine the site of origin of increased concentrations of plasma endothelin-1 in patients with severe preeclampsia. METHODS: Twelve patients with severe preeclampsia undergoing an indicated abdominal delivery had endothelin-1 levels measured from plasma specimens drawn from right and left uterine and antecubital veins before delivery and after placenta removal with uterine curettage. Twelve uncomplicated control patients undergoing abdominal delivery had endothelin-1 concentrations drawn by an identical protocol. Clinical staff members were blinded to endothelin-1 results and laboratory staff were blinded to patient group assignment and sample source. Endothelin-1 plasma concentrations were determined by radioimmunoassay and data were analyzed by paired t test. RESULTS: No difference in endothelin-1 concentration was noted with respect to placental location, central versus peripheral, or predelivery versus postdelivery sampling procedures. Overall, patients with preeclampsia had higher plasma concentrations of endothelin-1 (mean 11.0 +/- 6.6 pg/mL) compared with normotensive patients (mean 8.4 +/- 6.7 pg/mL, P < .005). CONCLUSION: The decidual-placental interface does not appear to be the source of increased plasma endothelin-1 concentrations found in severe preeclampsia. The origin of this increase remains uncertain.

A randomized trial of two vacuum extraction techniques.

OBJECTIVE: To determine whether two techniques of vacuum extraction delivery-continuous vacuum and intermittent vacuum-have different effects on maternal-fetal outcomes. METHODS: Patients to be delivered by vacuum extraction were randomized to receive continuous or intermittent vacuum. All deliveries were performed using the M-cup. In the continuous group, the level of vacuum was brought to 600 mmHg between contractions and was maintained at that level until delivery of the infant. Active efforts were made to prevent fetal loss-of-station between contractions by maintaining traction. In the intermittent group, the level of vacuum was decreased to 100 mmHg between contractions and no effort was made to prevent fetal loss-of-station. RESULTS: A total of 322 patients were randomized: 164 in the continuous arm and 158 in the intermittent group. The continuous method did not effect delivery faster (continuous 167 +/- 175 seconds versus intermittent 167 +/- 150 seconds; P = .97), nor did it lead to a reduction in method failures (continuous 12, intermittent nine; P = .72). The intermittent method did not appear to offer any benefit to the neonate regarding cephalhematoma formation (continuous 20, intermittent 17; P = .686) or any other measure of neonatal outcome. Maternal lacerations and episiotomy extensions were evenly distributed between the groups. Overall, the efficacy rate of the vacuum cup was 93.5% and the cephalhematoma rate was 11.5%. CONCLUSION: No differences in maternal or fetal outcome could be demonstrated if the level of vacuum was decreased between contractions or if an effort was made to prevent fetal loss-of-station. The clinical results obtained in this trial using the M-cup are similar to the published results with the stainless-steel Malmstrom cup.

Forceps and vacuum delivery: a survey of North American residency programs.

OBJECTIVE: To document resident instruction in operative vaginal delivery by forceps and vacuum. METHODS: A survey was sent to all 291 obstetrics-gynecology training programs in the United States and Canada. RESULTS: The overall response rate was 72% (210 of 291). Most programs (60%) have an operative vaginal delivery rate of 10% or less. Nearly all of the responding programs (199 of 209, 95%) teach operative vaginal delivery via the vacuum route; metallic cups are used in only 14% of centers. Forceps are the primary instrument in most programs (68%), but nearly one-third of responding centers use the vacuum method more often than forceps. Instruction in midpelvic operative vaginal delivery is offered in 64% of the programs, with forceps being more common by nearly a two-to-one ratio. Deep transverse arrest is handled initially by forceps by half of the respondents, whereas 28 and 22% would proceed with cesarean or attempt a vacuum extraction, respectively. CONCLUSION: Instruction in both types of operative vaginal delivery is found in most programs. The forceps are used more commonly, but vacuum is the preferred instrument in about one-third of training programs. Instruction in midpelvic delivery is offered in 64% of programs, but we noted a declining trend.

Operative vaginal delivery: a survey of fellows of ACOG.

OBJECTIVE: To document operative vaginal delivery rates of ACOG Fellows and to stratify practice patterns with regard to mid-pelvic delivery and deep transverse arrest by the time elapsed since residency. METHODS: A survey was mailed to a random sample of 1600 ACOG Fellows. Of the 597 respondents (37%), 558 who still practice obstetrics formed the study group. Selection bias regarding recipients of the survey was reduced by randomization by an uninvolved third party. The length of time since residency was categorized as 10 years or fewer ("recent," 31%), 11-20 years ("intermediate," 43%), and more than 20 years ("remote," 26%). RESULTS: The majority of respondents (338 of 558, 61%) reported an operative vaginal delivery rate of 15% or less. One hundred forty-two (25%) use only forceps, whereas 78 (14%) use vacuum extraction exclusively. More than half have abandoned mid-pelvic operative vaginal deliveries, and of the 41% who still perform these operations, about half use forceps. In cases of deep transverse arrest, about 25% perform cesarean delivery, whereas 26% and 42% use forceps or vacuum, respectively. Resident training and practice in vacuum delivery were more common in the recently trained groups (recent > intermediate > remote; P < .001). There were no differences among the groups with respect to attempting mid-pelvic operative vaginal delivery (P = .29), but the remote group was more likely to use forceps, whereas the recent group was more likely to use vacuum (P = .039). A large disparity existed among the groups regarding the management of deep transverse arrest, with vacuum use associated with group assignment (P < .001). CONCLUSIONS: The majority of respondents have an operative vaginal delivery rate of no more than 15%. Most respondents have abandoned mid-pelvic operative vaginal delivery. Practice patterns reflect differences in residency training; the more recently trained Fellows more often were taught and use vacuum for delivery.

Tips in diagnosing fetal skeletal anomalies.

A systematic approach to the prenatal and postnatal evaluation of the patient at risk for fetal skeletal anomalies is outlined. The more common anomalies are described within a differential diagnosis table, and a case study is presented.

Maternal hypoglycemia: is it associated with adverse perinatal outcome?

OBJECTIVE: To determine if maternal hypoglycemia is associated with adverse perinatal outcome, particularly low birth weight. STUDY DESIGN: In this prospective study, all patients after 24 weeks' gestation were screened for gestational diabetes using 50 gm of glucola (oral) followed by a 1-hour plasma glucose measurement and hypoglycemia was defined as < or = 88 mg/dl. RESULTS: In these 426 women the mean (+/- SD) 1-hour plasma glucose value was 99.8 +/- 22.7 mg/dl. Of these, 16 were diagnosed with gestational diabetes and 46 were lost to follow-up leaving 364 patients; 116 with hypoglycemia and 248 with euglycemia. Women with hypoglycemia weighed less at the beginning of pregnancy and at delivery, but total weight gain during pregnancy was similar between both groups. There was no difference between groups in maternal symptomatology, birth weight, or the rate of fetal growth restriction. CONCLUSION: Hypoglycemia on the 1-hour glucola screen is not predictive of fetal growth restriction or other adverse perinatal consequence.

Preinduction cervical ripening. A randomized trial of intravaginal misoprostol alone vs. a combination of transcervical Foley balloon and intravaginal misoprostol.

OBJECTIVE: To determine if the addition of a mechanical ripening agent (transcervical Foley balloon) to a pharmacologic agent (intravaginal misoprostol) improves the efficiency of preinduction cervical ripening. STUDY DESIGN: Singleton patients with an indication for delivery, unfavorable cervix (Bishop score < or = 5) and no contraindication to labor were randomly assigned to two groups: misoprostol alone (25 micrograms intravaginally every 3 hours for no more than 12 hr) or combination therapy (25-French transcervical Foley balloon inflated to 50 mL of sterile water with identical intravaginal misoprostol dosing). All patients received a history and physical examination (including Bishop score), preripening ultrasound, electronic fetal heart rate and contraction monitoring (to rule out spontaneous labor and document fetal well-being). Multiple variables of perinatal outcome were analyzed, including the main outcome variables of ripening-to-delivery time and cesarean section rate. RESULTS: During August 1998 to August 1999, 81 patients were randomized, 40 to misoprostol alone and 41 to combination therapy. There were no differences between the groups with respect to maternal demographics, preripening Bishop score, maternal complications, intrapartum intervention or neonatal outcome. The misoprostol group spent longer periods of time in active labor, and there was a trend for the combination group to require oxytocin for longer intervals. These findings did not significantly affect the total ripening-to-delivery time or cesarean section rate which were similar for both groups. CONCLUSION: The addition of mechanical ripening with a transcervical Foley balloon to intravaginal misoprostol did not improve the efficiency of preinduction cervical ripening. Mechanical and pharmacologic cervical ripening agents appear to act independently rather than synergistically.

Preinduction cervical ripening techniques compared.

OBJECTIVE: To assess the clinical efficacy of pharmacologic, mechanical and combination techniques of cervical ripening. STUDY DESIGN: From March 1997 to August 1998, all cervical-ripening patients at Lehigh Valley Hospital were randomly assigned to three groups: intravaginal misoprostol, intracervical Foley catheter, or combination prostaglandin E2 (PGE2) gel and Foley catheter. Inclusion criteria included Bishop score < or = 5 and no contraindication to labor. The remaining delivery process was actively managed according to established guidelines. Multiple variables in perinatal outcome were analyzed, with the cesarean section rate and time from ripening to delivery as the main outcome variables. RESULTS: Of the 205 patients, 65 were randomized to the misoprostol group, 71 to the Foley group and 69 to the catheter-and-gel group. There were no differences between groups in delivery indications, maternal demographics, ultrasound findings, labor interventions, intrapartum times, mode of delivery, postpartum complications or neonatal outcomes. The misoprostol group demonstrated a higher rate of uterine tachysystole and required oxytocin less when compared to the two catheter groups. CONCLUSION: The higher rate of uterine tachysystole with misoprostol did not increase the cesarean section rate. The higher rate of oxytocin required by the two catheter groups did not increase the delivery time intervals. There appears to be no benefit to adding intracervical or intravaginal PGE2 gel to the intracervical Foley balloon. The misoprostol and catheter ripening techniques have similar safety and efficacy.

Twins and preterm labor.

OBJECTIVE: To assess the effect of home uterine contraction assessment (HUCA) in twin pregnancies with preterm labor (PTL) at < 24 weeks' gestation. STUDY DESIGN: In this retrospective, analytic study, patients were stratified by whether HUCA had been prescribed before or after diagnosis of PTL. The main outcomes studied were time of PTL diagnosis and delivery as well as birth weight and need for neonatal intensive care unit (NICU) admission. In 63 patients, 32 were prescribed HUCA after PTL had been arrested at < 24 weeks (group I). Thirty-one women had HUCA prescribed at 20 weeks' gestational age and then developed PTL at < 24 weeks (group II). RESULTS: Labor was diagnosed at similar times in both groups (22.8 vs 23.4 weeks), but delivery was earlier in group I (27.6 weeks vs. 34.7 weeks) than in group II. The birth weight in group I was less (918 +/- 255 g), and of the 64 infants, 55 required NICU admission as compared to 2,340 +/- 525 g and 11 of 62 infants (P < .0001, .0001) in group II, respectively. CONCLUSION: Women with twin gestations and the diagnosis of PTL prior to 24 weeks deliver later in gestation, and their infants weigh more and have fewer NICU admissions if intensive prenatal surveillance is prescribed prior to the onset of labor.

Neonatal cephalohematoma from vacuum extraction.

OBJECTIVE: To identify factors involved in the development of fetal cephalohematoma from vacuum extraction. STUDY DESIGN: Patients at > or = 34 weeks' gestation were randomly assigned to delivery by vacuum (n = 322) using the continuous (n = 164) or intermittent (n = 158) technique. Neonatal outcome with cephalohematoma was analyzed subsequently and related to prospectively recorded data. RESULTS: Approximately equal numbers of cephalohematoma were recorded in the two groups (continuous 20, intermittent 17; P = .686). Station at point of application (P = .008), increasing asynclitism (P < .001) and increasing application to delivery time (P = .002) correlated significantly with cephalohematoma. Only the last two factors achieved significance after stepwise multiple logistic regression analysis. Factors that did not achieve statistical significance were gestational age (P = .755), birth weight (P = .982), instrumental rotation (P = .896) and previous vaginal delivery (P = .051). CONCLUSION: In this prospective, randomized, controlled trial of vacuum-assisted delivery, the only predelivery factor found to predispose to neonatal cephalohematoma formation was increasing asynclitism. Although cephalohematoma formation was more likely to develop as the duration of vacuum application increased during delivery, only 28% of neonates exhibited this finding when the time from vacuum application to delivery exceeded five minutes.

Lowering the cesarean rate at a small USAF hospital.

From July 1, 1988 to June 30, 1989, programs were initiated at the 93d Strategic Hospital at Castle AFB, California, to lower the cesarean (C/S) rate. Programs included vaginal birth after cesarean, external cephalic version, adequate labor documentation, and peer review of all C/S for fetal distress. One year prior (N = 467) was compared to the year after the start of these programs (N = 430). A significant decrease of 21.2% to 10.2% (p < 0.0001) was documented. We conclude that aggressive management of obstetrical patients can reduce the rate of C/S in a small USAF hospital without increasing maternal or neonatal risk.

A comparison study of pain associated with endocervical sampling techniques.

Endocervical curettage (ECC) is an important tool in the diagnosis and treatment of cervical neoplasia. Its use has been limited, however, because of the pain it can cause. We show that the use of a soft plastic curette cause statistically less pain without compromising the quantity or quality of the sample.

Pregnancy complicated by sickle hemoglobinopathy.

During the last decade it has been shown that patients with major sickle hemoglobinopathies can experience a normal reproductive outcome. This has been accomplished with early aggressive prenatal care, effective counseling, and appropriate intervention by providers with a high index of suspicion for factors that lead to untoward outcomes in such women. Because controversy surrounds the use of transfusion therapy for pregnant patients with sickle cell disease, individualization should depend on patient circumstances and provider experience because this is a key factor in the management of these women. New therapies for those with major sickle hemoglobinopathy are on the horizon, but their use in pregnancy awaits further evaluation.

Revisiting the short cervix detected by transvaginal ultrasound in the second trimester: why cerclage therapy may not help.

OBJECTIVE: The purpose of this study was to identify the risk factors that are associated with increased neonatal morbidity in patients who were treated for sonographic evidence of internal os dilation and distal cervical shortening during the second trimester. STUDY DESIGN: From May 1998 to June 2000 patients between 16 and 24 weeks of gestation with the following sonographic criteria were randomly assigned to McDonald cerclage or no cerclage: internal os dilation and either membrane prolapse into the endocervical canal at least 25% of the total cervical length but not beyond the external os or a shortened distal cervix <2.5 cm. Before randomization, all patients were treated identically with an amniocentesis, multiple urogenital cultures, and therapy with indomethacin and clindamycin for 48 to 72 hours. Except for the cerclage, all patients were treated identically after randomization. Multiple variables of perinatal outcome were analyzed. A regression model with gestational age at delivery as the dependent variable was constructed and repeated with neonatal morbidity as the dependent variable. This model was applied to 3 populations: the cerclage group, the no cerclage group, and both groups combined. RESULTS: Of the 135 patients, 20 patients declined randomization, and 2 patients were diagnosed with acute chorioamnionitis. Of the 113 patients remaining, 55 patients were randomly assigned to the cerclage group, and 58 patients were randomly assigned to the no cerclage group. There were 8 rescue cerclage procedures (4 in each group). Regression analysis showed that readmission for preterm labor, chorioamnionitis, and abruption were consistently associated with early gestational age at delivery and increased morbidity. Cerclage did not affect perinatal outcome. CONCLUSION: The sonographic findings of second trimester internal os dilation, membrane prolapse, and distal cervical shortening likely represent a common pathway of several pathophysiologic processes. Use of cerclage does not alter any perinatal outcome variables. Increased neonatal morbidity in these patients appears to be associated with subclinical infection, preterm labor, and abruption.

Does centralized monitoring affect perinatal outcome?

A retrospective study was performed comparing centralized monitoring to noncentralized monitoring in regard to perinatal outcome. The study was conducted at Lehigh Valley Hospital (Allentown, PA) between August 1994 and February 1995. All deliveries during a 28-week-period were studied retrospectively. The study was designed such that for 14 weeks all patients were centrally monitored (Group A). During the following 14 weeks, no patients were centrally monitored (Group B). Patients not requiring monitoring, such as elective cesarean sections, were excluded from the study. The variables that were studied were the 5-minute Apgar, cord blood pH, perinatal mortality, admissions to the neonatal intensive care unit (NICU), spontaneous vaginal deliveries, cesarean sections, and operative vaginal deliveries. A total of 1,622 deliveries occurred during the 28 weeks of antenatal care. Group A consisted of 805 centralized monitored patients and Group B had 817 noncentralized monitored patients. There was no statistical difference in the 5-minute Apgar, umbilical artery pH, perinatal mortality, or the NICU admissions between the two groups. However, there was a significant statistical difference in the percent of cesarean sections performed for nonreassuring fetal heart rate tracings (Group A, 17.89% vs. Group B, 12.16%; P = 0.02). The overall cesarean section rate was increased in the centrally monitored group (Group A, 23.6% vs. Group B, 18.1%; P = 0.01). There were also statistically significant differences in operative vaginal deliveries (forceps and vacuum) for fetal heart rate abnormalities between Group A, 0.52% vs. Group B, .39% (P = 0.05). Centralized monitoring may be associated with an increase in the overall cesarean section rate. In addition, the rate of operative vaginal and abdominal deliveries appears to be increased for the indication of nonreassuring fetal heart rate tracings with the use of centralized monitoring.

Familial inheritance of mandibular arch malformations affecting three individuals in one family.

Mandibular aplasia is defined as incomplete development of the mandibular process of the first brachial arch. Its prevalence is less than 1:70,000. It is usually associated with low-set ears, transposition of the viscera, congenital heart defects, and rib abnormalities, and is incompatible with life. In this case report, fetal demise at 26 weeks' gestation in a previous pregnancy revealed the phenotypic features listed. The second pregnancy described here resulted in therapeutic termination of a similar appearing fetus. Because of this recurrence and a positive family history, familial inheritance is postulated.

A randomized trial of cerclage versus no cerclage among patients with ultrasonographically detected second-trimester preterm dilatation of the internal os.

OBJECTIVE: The aim of this study was to compare perinatal outcomes of patients with second-trimester ultrasonographic evidence of preterm dilatation of the internal os treated with cerclage versus those of patients not treated with cerclage. STUDY DESIGN: From May 1998 through June 1999 patients with ultrasonographic evidence of preterm dilatation of the internal os between 16 and 24 weeks' gestation were randomly assigned to receive a McDonald cerclage or no cerclage. Before random assignment all patients underwent amniocentesis and urogenital cultures and then received 48 hours of therapy with indomethacin and antibiotics. After treatment each patient was followed up as an outpatient with bed rest and weekly ultrasonographic evaluation. RESULTS: Of the 61 patients 31 were randomly assigned to cerclage and 30 were randomly assigned to no cerclage. There were no differences between groups with respect to maternal demographic characteristics, risk factors for preterm birth, cervical measurements, rescue procedures, readmission, chorioamnionitis, and abruptio placentae. The mean gestational age at delivery (33.5 +/- 6.3 weeks) and the perinatal death rate (12. 9%) in the cerclage group were similar to the mean gestational age at delivery (34.7 +/- 4.7 weeks; P =.4) and the perinatal death rate (10.0%; P =.9) in the no-cerclage group. CONCLUSION: Treatment with McDonald cerclage of preterm dilatation of the cervix detected ultrasonographically during the second trimester did not improve perinatal outcomes.

Incidence of adverse cardiopulmonary effects with low-dose continuous terbutaline infusion.

OBJECTIVE: Our purpose was to determine the incidence of adverse cardiovascular effects of terbutaline sulfate when administered as a continuous subcutaneous infusion in women with arrested preterm labor. STUDY DESIGN: Over a 6-year period records from 8709 women prescribed this therapy for preterm labor that had previously been arrested with other intravenous tocolytics were reviewed. These women were assessed daily for cardiovascular complaints and tolerance of the medication, while either in the hospital or at the home (by telephone). The main outcomes studied were the occurrence of pulmonary edema, sustained cardiac arrhythmias, chest pain, or myocardial ischemia. Any maternal death regardless of cause was also reviewed. RESULTS: Of the 8709 subjects, 47 (0.54%) had one or more cardiopulmonary problems. Pulmonary edema developed in 28 patients (0.32%) while receiving continuous subcutaneous infusion of terbutaline, 5 at home and 23 in the hospital. Of the total, 17 women were being treated concurrently with large amounts of intravenous fluids and one to three other tocolytic agents. In the 11 remaining subjects, 4 were diagnosed with pregnancy-induced hypertension and/or multiple gestation. Nineteen patients experienced other adverse cardiovascular effects, including electrocardiogram changes, irregular heart rate, chest pain, or shortness of breath. CONCLUSIONS: Continuous terbutaline infusion for women with stabilized preterm labor is associated with much fewer adverse effects than previous literature regarding intravenous beta-adrenergic agonist therapy would suggest.