Transvaginal cervical length scans to prevent prematurity in twins: a randomized controlled trial.

BACKGROUND: Twin pregnancies are associated with an increased risk of perinatal morbidity and mortality primarily due to spontaneous preterm deliveries. The mean gestational age for delivery is 35.3 weeks and twins account for 23% of preterm births <32 weeks. A number of strategies have been proposed to prevent preterm deliveries: tocolytics, bed rest, hospitalization, home uterine activity monitoring, cerclage, and most recently, progesterone. Unfortunately, none have proven effective. Recent metaanalyses and reviews suggest that transvaginal cervical length (TVCL) ultrasound in the second trimester is a powerful predictor of preterm birth among asymptomatic women. Indeed, TVCL has the highest positive and negative predictive values for determining the risk of spontaneous preterm delivery in twin pregnancies. It follows that TVCL assessment may allow identification of a subset of twin pregnancies that re better candidates for interventions intended to prevent prematurity. OBJECTIVE: We sought to determine whether use of TVCL prolongs gestation in twin pregnancies. STUDY DESIGN: This is a multicenter, randomized, controlled trial of 125 dichorionic or monochorionic/diamniotic twin pregnancies without prior preterm birth <28 weeks. The study group (n = 63) had TVCL and digital exams monthly from 16-28 weeks and were managed with a standard algorithm for activity restriction and cerclage. The control group (n = 62) had monthly digital cervical examinations but no routine TVCL ultrasound examinations. The primary outcome was gestational age at delivery. Secondary outcomes included percentage of deliveries <35 weeks, and maternal and neonatal outcomes. RESULTS: The mean gestational age at delivery was 35.7 weeks (95% confidence interval [CI], 35.2-36.2) among those managed with TVCL and 35.5 weeks (95% CI, 34.7-36.4) among the control patients. The Kaplan-Meier estimates of deliveries <38 weeks were not significantly different between groups. This was true whether we compared curves with a log-rank test (P = .67), Breslow test (P = .67), or Tarone-Ware test (P = .64). The percentage of deliveries <35 0/7 weeks did not differ: 27.4% for subjects managed with routine TVCL and 28.6% for control subjects (relative risk, 0.96; 95% CI, 0.60-1.54). Our study had an 80% power to detect a 12-day difference in the gestational age at delivery with 95% confidence. CONCLUSION: The overall mean length of gestation and the percentage of women delivering <35 weeks did not differ between twin gestations managed with TVCL and digital exams monthly from 16-28 weeks with a standard algorithm for activity restriction and cerclage and controls who had monthly digital cervical examinations but no routine TVCL. Routine second-trimester transvaginal ultrasound assessment of cervical length is not associated with improved outcomes when incorporated into the standard management of otherwise low-risk twin pregnancies.

Case Report of a Triplet Pregnancy with Complete Hydatidiform Mole and Coexisting Twins.

Background: Triplet pregnancy with complete hydatidiform mole and coexisting twin fetuses is extremely rare with an unknown incidence. Case: Here, we present a case report of a pregnancy with twin fetuses and concurrent hydatidiform mole that resulted in the preterm delivery of one viable baby, the unfortunate intrauterine demise of the other twin, and successful treatment of gestational trophoblastic neoplasia in the postpartum period. Conclusion: This case highlights several important questions that arise for women who choose to carry a multiple gestation pregnancy with complete hydatidiform mole and describes complications that can occur. It is imperative to accurately assess risks and counsel individuals who elect to carry these pregnancies to provide the best possible outcomes.

Late-preterm birth: does the changing obstetric paradigm alter the epidemiology of respiratory complications?

OBJECTIVE: To analyze the effect of gestational age, delivery mode, and maternal-fetal risk factors on rates of respiratory problems among infants born 34 or more weeks of gestation over a 9-year period. METHODS: Retrospective analysis of prospectively collected maternal and neonatal data on all inborn births at 34 or more weeks of gestation at a single tertiary care center for the years 1990-1998. Specific diagnostic criteria were concurrently applied by a single investigator. RESULTS: Over the 9-year period, late-preterm births increased by 37%, whereas births at more than 40 weeks decreased by 39%, resulting in a decrease in median age at delivery from 40 weeks to 39 weeks (P<.001). Respiratory problems occurred in 705 term or late-preterm infants (4.9%), with clinically significant morbidity (respiratory distress syndrome, meconium aspiration syndrome, or pneumonia) least common at 39-40 weeks of gestation. Respiratory morbidity was greater among infants born by cesarean delivery or complicated vaginal delivery compared with uncomplicated cephalic vaginal delivery. The rate of respiratory morbidity did not change over time (1990-1992 1.3%, 1993-1995 1.5%, 1996-1998 1.4%, P=.746). The etiologic fraction for respiratory morbidity did not change over time for infants 34-36 weeks but decreased twofold for infants born after 40 weeks. CONCLUSION: Over the 9-year study period, reduced respiratory morbidity associated with decreased births after 40 weeks were offset by the adverse respiratory effect of increased cesarean delivery rates and increased late-preterm birth rates.

Postcesarean delivery adhesions associated with delayed delivery of infant.

OBJECTIVE: The purpose of this study was to estimate the incidence of adhesions after cesarean deliveries and to determine their impact on delivery and infant well-being. STUDY DESIGN: This was a retrospective cohort analysis with chart review. The charts of 542 women who had undergone primary (265 women) or repeat cesarean (277 women) deliveries were reviewed. The incidence, severity, and locations of adhesions; delivery time; cord blood pH, and Apgar scores were noted. RESULTS: After the first cesarean delivery, 100 of 217 women (46%) had pelvic adhesive disease; 48 of 64 women (75%) who underwent a third cesarean delivery and 5 of 6 women (83%) who underwent a fourth cesarean delivery had formed pelvic adhesive disease. Compared with primary cesarean section, delivery of the infant was delayed 5.6 minutes (52%) with 1 previous cesarean birth, 8.5 minutes (79%) after 2 cesarean birth, and 18.1 (169%) during the fourth cesarean birth (P < 0.001 for all comparisons). CONCLUSION: A high percentage of cesarean deliveries result in adhesive disease, which delays repeat cesarean delivery of the fetus. The potential for adhesive disease should be included in counseling regarding primary elective cesarean births.

Does local anesthesia decrease pain perception in women undergoing amniocentesis?

OBJECTIVE: The null hypothesis is that local anesthesia does not decrease pain perception during amniocentesis. STUDY DESIGN: We performed a prospective randomized study comparing local anesthesia (1% lidocaine) with no anesthesia before amniocentesis in a racially diverse population. Immediately after the procedure, subjects were asked to assess their pain using both a Visual Analogue Scale and a 101-point Numerical Rating Scale. RESULTS: Two hundred four women were enrolled; 101 women received local, 102 women received no local, and 1 woman declined the amniocentesis after randomization. There was no difference in pain perception between the 2 groups as measured by either the visual analogue scale or the numeric rating scale (P = .28 and .18 respectively). The correlation coefficient between the 2 pain scales was strong with 0.86 for the local group and 0.92 for the no local group, (P < .001). CONCLUSION: Administration of local anesthesia before amniocentesis does not decrease maternal pain perception.

Severe hemolytic disease of the newborn due to anti-Cw.

BACKGROUND: Pregnancies complicated by Rh isoimmunization have decreased significantly since the widespread use of Rh immune globulin. Uncommon red blood cell antigens have therefore become more clinically evident. We report a case of anti-Cw immunization that resulted in severe fetal anemia that required multiple transfusions. CASE: A 28-year-old multigravida presented to our service at 18 weeks of gestation with her fourth pregnancy. Her pregnancy was complicated by anti-Cw isoimmunization that resulted in severe fetal anemia requiring in utero fetal blood transfusions. CONCLUSION: While previous reports recommend only postpartum surveillance when Cw isoimmunization is present, we report a case resulting in severe fetal anemia.

Complications of third-trimester amniocentesis using continuous ultrasound guidance.

OBJECTIVE: The objective of the study was to estimate the risks of third-trimester amniocentesis with continuous ultrasound guidance. METHODS: Cohort study. We reviewed the medical records of women who had an amniocentesis with continuous ultrasound guidance after 30 weeks' gestation at a single institution from January 1991 through December 1994. For procedures performed from January 1991 to February 1994, we obtained information from a chart review. From March 1994 to December 1994, we collected data prospectively. The primary outcome was whether or not there were any complications within 48 hours of the procedure. We also sought to determine any risk factors associated with complications. RESULTS: Complete records and data were available for 562 amniocenteses during the study period. The mean gestational age at the time of amniocentesis was 34.9 weeks. Of the 562 procedures, five (0.8%) were unsuccessful and 50 (9%) required more than one needle stick. The complication rate was 0.7% (95% confidence level (CI) = 0.02%, 1.9%). These included spontaneous labor in a preterm gestation (1), premature rupture of the membranes (1), placental abruption (1), and fetal-maternal hemorrhage (1). No patient required an emergency cesarean delivery and none suffered a perinatal death (95% CI 0, 0.8%). Complications were not associated with the number of needle sticks, the presence of bloody amniotic fluid, or the level of operator experience. CONCLUSIONS: Third-trimester amniocentesis performed with continuous ultrasound guidance has a high success rate and low risk for complications.

Changing obstetric practices associated with decreasing incidence of meconium aspiration syndrome.

OBJECTIVE: To describe changes in neonatal and obstetric practices that may have contributed to the decreasing incidence of meconium aspiration syndrome in our population during this time. METHODS: We compared neonatal and obstetric characteristics of 61 infants diagnosed with meconium aspiration syndrome with 1365 infants born through moderate or thick meconium-stained amniotic fluid at more than 37 weeks' completed gestation. Data were prospectively collected, and all respiratory diagnoses were concurrently made. Three distinct birth year groups were analyzed based on changing obstetric practice paradigms. RESULTS: Meconium aspiration syndrome decreased nearly four-fold from 1990-1992 to 1997-1998 (5.8% to 1.5% of meconium-stained infants more than 37 weeks; P <.003). The only change in neonatal characteristics was a 33% decrease in births more than 41 weeks with a reciprocal 33% increase in births 38-39 weeks during 1997-1998. Significant changes in obstetric practice included more frequent diagnosis of nonreassuring fetal heart rate patterns, greater use of amnioinfusion, and increased cesarean delivery rate in 1997-1998. By logistic regression analysis, the only consistent risk factor for meconium aspiration syndrome across all three epochs was the presence of tracheal meconium. CONCLUSION: Reduction in post-term delivery was the most important factor in reducing meconium aspiration syndrome.