The association between threatened preterm labour and perinatal outcomes at term: a population-based cohort study.

OBJECTIVE: To estimate the association between threatened preterm labour (TPTL) and perinatal outcomes of infants born at term. DESIGN: A population-based cohort study of perinatal outcomes following TPTL <37 weeks of gestation with delivery at term. SETTING: Nova Scotia, Canada. POPULATION: All non-anomalous, singleton pregnancies ≥37 weeks of gestation without antepartum haemorrhage from 1988 to 2019. METHODS: Using data from the Nova Scotia Atlee Perinatal Database, TPTL was defined as pregnancies with a hospital admission between 20 and 37 weeks of gestation, with a diagnosis code denoting TPTL with administration of antenatal corticosteroids, or with administration of any tocolysis. Poisson regression models were used to estimate the risk ratios (RR) with 95% CI of maternal and perinatal outcomes in women who had an episode of TPTL relative to those who did not. MAIN OUTCOME MEASURES: Birthweight for gestational age below the tenth centile and a composite of perinatal mortality or severe perinatal morbidity. RESULTS: Of 256 599 term deliveries meeting the inclusion criteria, 2278 (0.9%) involved TPTL. The risks of the primary outcomes were higher among those with TPTL relative to those without: birthweight for gestational age below the tenth centile (RR 1.24, 95% CI 1.11-1.39) and the composite of perinatal mortality/severe perinatal morbidity (RR 1.33, 95% CI 1.15-1.54). CONCLUSIONS: Although the prevalence of TPTL in term deliveries is low, affected pregnancies are at increased risk for adverse perinatal outcomes. Increased fetal surveillance should be considered in the management of pregnancies affected by TPTL.

Nutrient-induced spore germination of a Bacillus amyloliquefaciens biocontrol agent on wheat spikes.

AIMS: In this study, we investigated the feasibility of applying nutrient germinants to plant surfaces to stimulate the spore germination of the plant disease biocontrol agent Bacillus amyloliquefaciens strain TrigoCor. METHODS AND RESULTS: Using the terbium chloride assay and phase-contrast microscopy, we screened potential germinants of TrigoCor spores and found that a combination of d-glucose, d-fructose and potassium chloride (GFK), in addition to either l-asparagine (Asn-GFK) or l-alanine (Ala-GFK), induced maximal levels of TrigoCor spore germination in vitro. The germinant mixture Asn-GFK was also able to significantly stimulate Bacillus spore germination on wheat surfaces. CONCLUSIONS: The successful in vivo stimulation of Bacillus spore germination suggests that nutrient-induced spore germination on plant surfaces is a feasible strategy for improving Bacillus biocontrol. SIGNIFICANCE AND IMPACT OF THE STUDY: One of the challenges of applying Bacillus biological control agents to aboveground plant parts is that Bacillus cells transition to a metabolically dormant spore state on plant surfaces, making them unable to prevent subsequent pathogen attacks. This study demonstrates that using nutrients to stimulate Bacillus spore germination in vivo is a promising option for improving disease control and should be pursued further.

Iturin levels on wheat spikes linked to biological control of Fusarium head blight by Bacillus amyloliquefaciens.

The TrigoCor strain of Bacillus amyloliquefaciens provides consistent control against Fusarium head blight of wheat in controlled settings but there is a lack of disease and deoxynivalenol suppression in field settings. Since production of antifungal compounds is thought to be the main mode of action of TrigoCor control, we quantified levels of a key family of antifungal metabolites, iturins, as well as monitored Bacillus populations on wheat spikes over 14 days post-application in both the greenhouse and the field. We found that initial iturin levels on spikes in the greenhouse were three times greater than on spikes in the field, but that by 3 days post-application, iturin levels were equivalent and very low in both settings. We also determined that iturins declined rapidly over a 3-day post-application period on wheat spikes in both environments, despite the presence of significant Bacillus populations. Greenhouse trials and antibiosis tests indicated that the lower iturin levels on wheat spikes in the field could be a major factor limiting disease control in field settings. Future efforts to improve Bacillus disease control on wheat spikes and in the phyllosphere of various plants should focus on maintaining higher levels of iturins over critical infection periods.

Effects of environmental tobacco smoke on perinatal outcomes: a retrospective cohort study.

OBJECTIVE: To evaluate the effects of environmental tobacco smoke (ETS) on perinatal outcomes. DESIGN: Retrospective cohort study. SETTING: Newfoundland and Labrador, Canada. POPULATION: Nonsmoking women with singleton gestations who delivered 1 April 2001-31 March 2009, identified through the Newfoundland and Labrador Provincial Perinatal Database. METHODS: Women who self-reported exposure to ETS were compared with those who reported no exposure. Univariate analyses and multivariate linear and logistic regression analyses (adjusting for maternal age, parity, partnered status, work status, level of education, body mass index, alcohol use, illicit drug use and gestational age) were performed and odds ratios(OR; or adjusted differences) with 95% confidence intervals were calculated. MAIN OUTCOME MEASURES: Birthweight, birth length, head circumference and stillbirth. Secondary outcomes included gestational age at delivery, preterm birth <37 and <34 weeks of gestation, prelabour rupture of membranes, Apgar score, endotracheal intubation for resuscitation, neonatal intensive care unit admission, congenital anomalies, respiratory distress syndrome, intraventricular haemorrhage, neonatal bacterial sepsis, jaundice and neonatal metabolic abnormalities. RESULTS: A total of 11,852 women were included: 1202(11.1%) exposed to ETS and 10,650 (89.9%) not exposed. Exposure to ETS was an independent risk factor for lower mean birthweight (-53.7 g, 95% CI -98.4 to -8.9 g), smaller head circumference (-0.24 cm, 95% CI -0.39 to -0.08 cm), shorter birth length (-0.29 cm, 95% CI -0.51 to -0.07 cm), stillbirth (OR 3.35, 95% CI 1.16-9.72, P = 0.026), and trends towards preterm birth <34 weeks (OR 1.87, 95% CI 1.00-3.53, P = 0.05) and neonatal sepsis (OR 2.96, 95% CI 0.99-8.86). CONCLUSIONS: Exposure of nonsmoking pregnant women to ETS is associated with a number of adverse perinatal outcomes including lower birthweight, smaller head circumference and stillbirth, as well as shorter birth length. This information is important for women, their families and healthcare providers, and reinforces the continued need for increased public policy and education on prevention of exposure to ETS.

Transvaginal ultrasonographic measurement of cervical length in asymptomatic high-risk women with a short cervical length in the previous pregnancy.

OBJECTIVE: To determine if asymptomatic women at high risk of preterm delivery who had a short cervical length in their previous pregnancy and delivered at term are at increased risk of having a short cervical length in their next pregnancy, and whether they are at increased risk of preterm birth. METHODS: This retrospective cohort study included high-risk (those with a history of spontaneous preterm birth, uterine anomaly or excisional treatment for cervical dysplasia) asymptomatic women who were pregnant with a singleton gestation delivering between April 2003 and March 2010, who had had a previous pregnancy and who had transvaginal ultrasonographic cervical length measurement performed at 16-30 weeks' gestation in both pregnancies. Comparison was among women who had a short cervical length (< 3.0 cm) in their previous pregnancy but delivered at term in that pregnancy (Short Term Group), women with a history of a normal cervical length (≥ 3.0 cm) in their previous pregnancy delivering at term (Long Term Group), and women who had a short cervical length (< 3.0 cm) in their previous pregnancy delivering preterm (Short Preterm Group). Primary outcomes were spontaneous preterm birth at < 37 weeks' gestation and cervical length. Secondary outcomes were spontaneous preterm birth at < 35 weeks and < 32 weeks, low birth weight, maternal outcomes and neonatal morbidity. RESULTS: A total of 62 women were included. Women in the Short Term Group were more likely to have a short cervical length in their next pregnancy compared with those in the Long Term Group (10/23 (43.5%) vs. 4/26 (15.4%), respectively) but not as likely as women in the Short Preterm Group (9/13 (69.2%); P=0.003). Women in the Short Term Group were not at an increased risk of spontaneous preterm birth at < 37 weeks in the next pregnancy compared with women in the Long Term Group (2/23 (8.7%) vs. 2/26 (7.7%), respectively), but women in the Short Preterm Group were at an increased risk (6/13 (46.2%); P<0.0001). Compared with women in the Short Term and Long Term groups, women in the Short Preterm Group were also at an increased risk of threatened preterm labor (6/23 (26.1%) and 4/26 (15.4%) vs. 9/13 (69.2%), respectively; P=0.002) and of receiving corticosteroids for fetal lung maturation (6/23 (26.1%) and 4/26 (15.4%) vs. 11/13 (84.6%), respectively; P<0.0001). CONCLUSION: Although high-risk asymptomatic women with a short cervical length in their previous pregnancy who delivered at term are at increased risk of having a short cervix in their next pregnancy, they are not at increased risk of preterm birth.

Transvaginal sonographic measurement of cervical length to predict preterm birth in asymptomatic women at increased risk: a systematic review.

OBJECTIVES: To estimate the ability of cervical length measured by transvaginal ultrasonography in asymptomatic high-risk women to predict spontaneous preterm birth. METHODS: MEDLINE, PubMed, EMBASE and the Cochrane Library were searched for articles published in any language between January 1980 and July 2006, using the keywords 'transvaginal ultrasonography' or ('cervix' and ('ultrasound' or 'ultrasonography' or 'sonography')); and ('preterm' or 'premature') and ('delivery' or 'labour/labor' or 'birth'), identifying cohort studies evaluating transvaginal ultrasonographic cervical length measurement in predicting preterm birth in asymptomatic women who were considered at increased risk (because of a history of spontaneous preterm birth, uterine anomalies or excisional cervical procedures), with intact membranes and singleton gestations. The primary analysis included all studies meeting the inclusion criteria. Secondary analyses were also performed specifically for (1) women with a history of spontaneous preterm birth; (2) those who had undergone an excisional cervical procedure; and (3) those with uterine anomalies. RESULTS: Fourteen of 322 articles identified (involving 2258 women) met the criteria for systematic review. Cervical length measured by transvaginal ultrasonography predicted spontaneous preterm birth. The shorter the cervical length cut-off the higher the positive likelihood ratio (LR). The most common cervical length cut-off was < 25 mm. Using this cut-off to predict spontaneous preterm birth at < 35 weeks, transvaginal ultrasonography at < 20 weeks' gestation revealed LR+ = 4.31 (95% CI, 3.08-6.01); at 20-24 weeks, LR+ = 2.78 (95% CI, 2.22-3.49); and at > 24 weeks, LR+ = 4.01 (95% CI, 2.53-6.34). In women with a history of spontaneous preterm birth (six studies involving 663 women) cervical length at < 20 weeks revealed LR+ = 11.30 (95% CI, 3.59-35.57) and at 20-24 weeks LR+ = 2.86 (95% CI, 2.12-3.87), but there were limited data on the use of cervical length of more than 24 weeks in this group (one study involving 42 women). In women who had had excisional cervical procedures, two studies presented data on cervical length (one at < 24 weeks and one at > 24 weeks), finding cervical length at < 24 weeks to be predictive of spontaneous preterm birth at < 35 weeks (LR+ = 2.91, 95% CI, 1.69-5.01). One study (of 64 women) evaluated cervical length in women with uterine anomalies, finding it predictive of spontaneous preterm birth at < 35 weeks (LR+ = 8.14, 95% CI, 3.12-21.25). CONCLUSION: Cervical length measured by transvaginal ultrasonography in asymptomatic high-risk women predicts spontaneous preterm birth at < 35 weeks. Further research may be warranted to evaluate the use of transvaginal ultrasonography after 24 weeks' gestation in women with a history of spontaneous preterm birth, and in women with uterine anomalies.

Use of transvaginal ultrasonography to predict preterm birth in women with a history of preterm birth.

OBJECTIVE: To investigate whether cervical length measured by transvaginal ultrasonography predicts spontaneous preterm birth at < 35 weeks' gestation in women with a history of spontaneous preterm birth, stratified by spontaneous preterm birth history subtype (preterm premature rupture of membranes (PPROM) or preterm labor with intact membranes at onset of labor). METHODS: This retrospective cohort study included women with a history of spontaneous preterm birth that were subsequently pregnant with singleton gestations, compared with a low-risk control group. Transvaginal ultrasonographic cervical lengths were measured at 24 to 30 weeks of gestation. The primary outcome was spontaneous preterm birth at < 35 weeks. Secondary outcomes included spontaneous preterm birth at < 37 weeks and < 34 weeks, low birth weight, Cesarean delivery and perinatal morbidity and mortality. Multiple logistic regression analysis was used to control for potential confounders and calculate odds ratios and 95% confidence intervals. Receiver-operating characteristics (ROC) curves were used to determine the best cut-off for transvaginal ultrasound cervical length in predicting spontaneous preterm birth at < 35 weeks. RESULTS: Women with a history of spontaneous preterm birth with intact membranes at onset of labor (n = 42) had a shorter cervical length (3.28 cm) than women with a history of spontaneous preterm birth with PPROM at onset of labor (n = 48, cervical length 3.77 cm; P = 0.019), and both subgroups had shorter cervical lengths than the low-risk control group (n = 103, cervical length 4.30 cm; P < 0.0001). Both subgroups were associated with spontaneous preterm birth at < 35 weeks, < 37 weeks, < 34 weeks and birth weight < 2500 g. ROC curves determined that the best cut-off for cervical length to predict spontaneous preterm birth at < 35 weeks was 3.0 cm. By multiple logistic regression analysis, the only independent predictors of spontaneous preterm birth at < 35 weeks were cervical length < 3.0 cm, a history of spontaneous preterm birth and antepartum bleeding in the current pregnancy. In women with a history of spontaneous preterm birth, a cervical length as measured by transvaginal ultrasonography of < 3.0 cm had a sensitivity of 63.6%, specificity of 77.2%, positive predictive value of 28.0% and negative predictive value of 93.8%, for preterm birth at < 35 weeks. CONCLUSION: Women with a history of spontaneous preterm birth with preterm labor and intact membranes at the onset of labor have shorter cervices than women with a history of spontaneous preterm birth and PPROM at the onset of labor, and both groups have shorter cervices than a low-risk control group. Both groups of women with a history of spontaneous preterm birth have an increased risk of recurrent spontaneous preterm birth at < 35 weeks, and this is predicted by a transvaginal ultrasound cervical length of < 3.0 cm.

A comparison of computed tomography and radionuclide scanning for detection of brain metastases in small cell lung cancer.

Neurologic history and examination, radionuclide brain scans (RN), and computed tomographic brain scans (CT) were performed at diagnosis and sequentially in 153 consecutive patients with small cell lung cancer (SCLC) to assess the sensitivity and accuracy of these screening methods and to determine whether the early detection of brain metastases influences survival. CT scans (sensitivity, 98%; positive predictive accuracy, 98%) were superior to RN scans (sensitivity, 71%; positive predictive accuracy, 86%) in patients with or without neurologic signs or symptoms. However, CT scans were positive in only 6% of asymptomatic patients at diagnosis and 13% of asymptomatic patients after systemic therapy. Brain metastases detected by CT scan were the sole site of extensive-stage disease in 6% of patients at diagnosis. Despite the enhanced ability of CT scans to detect asymptomatic lesions, survival after therapeutic cranial irradiation was similar for asymptomatic and symptomatic patients. The results suggest that CT brain scans should be used routinely in SCLC patients with neurologic signs or symptoms, at diagnosis (when treatment decisions are based on stage), and at six-month intervals in patients with prior brain metastases and in whom erratic follow-up is likely.

Peptide mimics of SNARE transmembrane segments drive membrane fusion depending on their conformational plasticity.

SNARE proteins are essential for different types of intracellular membrane fusion. Whereas interaction between their cytoplasmic domains is held responsible for establishing membrane proximity, the role of the transmembrane segments in the fusion process is currently not clear. Here, we used an in vitro approach based on lipid mixing and electron microscopy to examine a potential fusogenic activity of the transmembrane segments. We show that the presence of synthetic peptides representing the transmembrane segments of the presynaptic soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) synaptobrevin II (also referred to as VAMP II) or syntaxin 1A, but not of an unrelated control peptide, in liposomal membranes drives their fusion. Liposome aggregation by millimolar Ca(2+) concentrations strongly potentiated the effect of the peptides; this indicates that juxtaposition of the bilayers favours their fusion in the absence of the cytoplasmic SNARE domains. Peptide-driven fusion is reminiscent of natural membrane fusion, since it was suppressed by lysolipid and involved both bilayer leaflets. This suggests transient presence of a hemifusion intermediate followed by complete membrane merger. Structural studies of the peptides in lipid bilayers performed by Fourier transform infrared spectroscopy indicated mixtures of alpha-helical and beta-sheet conformations. In isotropic solution, circular dichroism spectroscopy showed the peptides to exist in a concentration-dependent equilibrium of alpha-helical and beta-sheet structures. Interestingly, the fusogenic activity decreased with increasing stability of the alpha-helical solution structure for a panel of variant peptides. Thus, structural plasticity of transmembrane segments may be important for SNARE protein function at a late step in membrane fusion.

Results of therapeutic cranial irradiation in small cell lung cancer.

A large proportion of patients with small cell lung cancer develop intracranial metastases which are often severely disabling. The optimal radiotherapeutic program for treating these metastases is unknown. We therefore evaluated objective response rates, response duration, and survival after therapeutic cranial irradiation in 59 patients with proven brain metastases from small cell lung cancer. Objective responses to a variety of doses and schedules were observed in 37 (63%) patients. However, progression of intracranial disease after radiotherapy was common, with 24 responding patients having relapsed in the brain prior to death. The actuarial likelihood of remaining free of progressive brain tumor at 1 year was only 37% in complete and 0% in partial responders. Patients who received radiation doses of more than 40 Gy had longer response durations than those given lower doses, although patient selection could well explain this observation. Brain metastases presenting after initiation of systemic chemotherapy or occurring in conjunction with other sites of extrathoracic disease were associated with a poor prognosis. In patients who present with brain metastases as the sole site of metastatic disease, higher doses of cranial irradiation should be considered, in view of the high intracranial relapse rate associated with currently accepted dose and fractionation schedules.

The development of a genetic map for meadowfoam comprised of amplified fragment length polymorphisms.

Limnanthes alba Benth. (meadowfoam), a diploid ( x=5) winter annual, produces novel very long-chain seed oils (C(20) and C(22)) with less than 2% saturated fatty acids. The first genetic map of meadowfoam, a recently domesticated species, is described herein. Two phenotypically diverse inbred lines, OMF40-11 ( L. alba ssp. alba) and OMF64 ( L. alba ssp. versicolor), were screened for amplified fragment length polymorphisms (AFLPs) using 16 primer combinations. Twenty three percent of the AFLP bands (415 out of 1,801) were polymorphic between OMF40-11 and OMF64. One hundred (OMF40-11xOMF64)xOMF64 BC(1) progeny were genotyped for 107 polymorphic AFLP markers produced by nine AFLP primer combinations. One hundred and three AFLP loci amalgamated into five linkage groups with 14 to 28 loci per linkage group (four loci segregated independently). The map was 698.5-cM long with a mean interlocus spacing of 6.7 cM and no dense clustering of loci. The segregation ratios for 25 loci (23.2%) were significantly distorted. Twenty one of the distorted loci (84%) had an excess of L. alba ssp. versicolor (recurrent parent) alleles. The distorted loci, apart from one locus on linkage group 4, were distally clustered on both ends of linkage groups 1, 4 and 5. The development of the map was facilitated by the small chromosome number, an abundance of restriction site polymorphisms between the two subspecies (23%), and a high multiplex ratio of the AFLP markers (112 per primer combination).

Transvaginal ultrasound and digital examination in predicting successful labor induction.

OBJECTIVE: To compare transvaginal ultrasound and digital cervical examination in predicting successful induction in post-term pregnancy. METHODS: Transvaginal ultrasound and digital vaginal examinations were performed on 122 women at 41 or more weeks' gestation, immediately before labor induction. Ultrasound assessments of cervical length, dilatation, and presence of funneling were compared with the components of the Bishop score. The primary outcome was the rate of vaginal delivery. Secondary outcomes assessed included the rates of active labor in 12 hours, vaginal delivery in 12 and 24 hours, mean duration of latent phase, and induction to vaginal delivery interval. Linear and multiple logistic regression models were generated to identify factors independently associated with successful induction. RESULTS: No ultrasound characteristic predicted primary or secondary outcomes. Bishop score (odds ratio [OR] 2.98, 95% confidence interval [CI] 1.71, 5.20), cervical position (OR 4.35, 95% CI 1.41, 12.50), and maternal age (OR 1.15, 95% CI 1.01, 1.30) independently predicted vaginal delivery. Maternal weight (OR 0.96, 95% CI 0.94, 0.98), cervical dilatation (OR 6.08, 95% CI 1.70, 21.68), and effacement (OR 2.34, 95% CI 1.16, 4.73) independently predicted active labor in 12 hours. Independent predictors of vaginal delivery in 12 hours were induction method (P <.001), cervical dilatation (OR 11.16, 95% CI 3.17, 39.29), gravidity (OR 2.06, 95% CI 1.13, 3.77), and maternal weight (OR 0.96, 95% CI 0.93, 0.99). Cervical effacement (OR 2.70, 95% CI 1.59, 4.57) and parity (OR 7.10, 95% CI 2.22, 22.72) independently predicted vaginal delivery in 24 hours. Maternal weight, cervical position, and cervical dilatation were independently associated with latent phase labor duration. Factors independently associated with length of induction to delivery interval were parity, cervical effacement, and maternal weight. CONCLUSION: Transvaginal ultrasound does not predict successful labor induction in post-term pregnancy as well as digital cervical examination.

Acardiac twin pregnancy with neonatal resolution of donor twin cardiomyopathy.

BACKGROUND: Twin reverse arterial perfusion, as with acardiac fetuses, is a rare complication of multifetal pregnancy. Prognosis of the donor twin is guarded because of the high risk of cardiac failure, polyhydramnios, and preterm delivery. CASE: A 40-year-old woman, gravida 4, para 3, was diagnosed at 19 weeks' gestation with a twin pregnancy complicated by an acardiac, acephalic fetus. Serial amniocenteses were done to decompress the hydramnios between 27 and 33 weeks. Ultrasonography showed ventricular septal hypertrophy in the donor twin at 27 weeks, and cesarean delivery was done at 33 weeks. The neonatal course was complicated by hypertrophic cardiomyopathy, which resolved without sequelae by 1 year of age. CONCLUSION: Antenatal sonographic monitoring of interventricular septal thickness can be a useful marker to predict neonatal cardiac sequelae.

Excessive uterine activity accompanying induced labor.

OBJECTIVE: To estimate the incidence and timing of excessive uterine activity accompanying induction of labor with misoprostol using different routes (oral or vaginal) and forms (intact tablet or crushed) and to compare these with dinoprostone gel, oxytocin, and spontaneous labor. METHODS: This retrospective cohort study included 519 women at term who had labor induced and 86 women at term in spontaneous labor. Induction agents included misoprostol, dinoprostone, or oxytocin. Fetal heart rate and uterine activity tracings were analyzed independently by three maternal-fetal medicine physicians. The diagnosis of tachysystole or hyperstimulation required the agreement of two or more reviewers. RESULTS: The incidence of tachysystole was highest with misoprostol administered by vaginal tablet (misoprostol vaginal tablet 50 microg every 4 hours, 48.6%; vaginal tablet crushed 50 microg and suspended in hydroxyethyl gel every 4 hours, 30.7%, P =.009; oral tablet 50 microg every 4 hours, 22.2%, P =.001; oral tablet crushed 50 microg every 4 hours, 15.5%, P <.001; dinoprostone gel, 33.0%, P =.022; intravenous oxytocin, 30.2%, P =.027; and spontaneous onset of labor, 23.3%, P <.001). Hyperstimulation occurred more often with dinoprostone gel (16.5%) than with other forms of induction or spontaneous labor. Hyperstimulation occurred significantly more often with vaginal misoprostol crushed tablet (7.9%) and vaginal misoprostol intact tablet (7.6%) than with crushed oral misoprostol (1.0%) (P =.016 and.018, respectively). There was a shorter time to tachysystole with increasing doses of vaginal misoprostol tablet (P =.01). CONCLUSION: The incidence of tachysystole and hyperstimulation, and time to tachysystole, varied depending on the route and form of misoprostol given.

Transvaginal ultrasound in the prediction of preterm delivery: singleton and twin gestations.

OBJECTIVE: To compare, in singleton and twin pregnancies, the effectiveness of transvaginal ultrasound versus digital examination in predicting preterm delivery in women with suspected preterm labor. METHODS: Transvaginal ultrasound and pelvic examinations were performed on patients admitted with suspected preterm labor between 23 and 33 weeks' gestation. Ultrasound assessment of cervical length and the presence of funneling with fundal pressure were recorded for each patient, and the results were compared with dilatation and effacement as assessed by digital examination for the prediction of preterm delivery in the two groups (singletons and twins). RESULTS: One hundred sixty-two subjects were recruited (136 singletons and 26 twin pregnancies), with no significant demographic differences between the groups. Overall, 33% of the participants delivered preterm (27% of singletons, 62% of twins). Using receiver operating characteristics curves, the best cutoff points were 30 mm for endocervical length at ultrasound, 50% for effacement, and 1.5 cm for dilatation. Of these, the best predictor was endocervical length, which was a better predictor in singleton than in twin pregnancies. Of the potential predictors, including endocervical length, funneling, dilatation, and effacement, only endocervical length was an independent predictor of preterm delivery at less than 34 weeks' gestation for both singletons and twins by multiple logistic regression. When analyzed for delivery at less than 37 weeks' gestation, this relation held true for singletons but not twins. Endocervical length less than 30 mm had a sensitivity of 81% and 75%, specificity of 65% and 30%, positive predictive value of 46% and 63%, and negative predictive value of 90% and 43% for singleton and twin pregnancies, respectively, in predicting spontaneous birth at less than 37 weeks' gestation. CONCLUSION: Between 23 and 33 weeks' gestation, transvaginal ultrasound assessment of endocervical length is superior to funneling and digital examination in predicting preterm delivery in patients who present with suspected preterm labor, and is a better predictor in singletons than in twins.

A masked randomized comparison of oral and vaginal administration of misoprostol for labor induction.

OBJECTIVE: To test the null hypothesis that administering misoprostol orally or vaginally will result in no difference in time to vaginal birth, and to determine whether different frequencies of tachysystole and hyperstimulation are associated with route of administration. METHODS: Two hundred six women after 37 completed weeks' gestation who presented with an indication for induction were randomly assigned to receive misoprostol (50 microg) either orally or vaginally every 4 hours as needed to induce labor. Placebo use and allocation concealment accomplished blinding until data analysis was completed. Sample size was calculated to allow a two-tailed alpha of .05 and power (1-beta) of 80%. All fetal heart rate and uterine activity graphs were classified according to Curtis' criteria before induction groups were unmasked. RESULTS: Analysis involved 104 women in the oral group and 102 in the vaginal group. The mean time (+/-standard deviation) to vaginal birth with oral misoprostol was 1072 (+/-593) minutes compared with 846 (+/-385) minutes with the vaginal protocol (P=.004). There were no significant differences in cesarean rate, epidural use, or neonatal outcomes. More frequent tachysystole for 20 minutes (P < .01) and hyperstimulation (P < .04) were observed with vaginal misoprostol. No neonatal asphyxia occurred in either group. CONCLUSION: Misoprostol effectively induces labor, given orally or vaginally. There is a shorter interval to vaginal birth with vaginal application; however, the more frequent occurrence of fetal heart rate graph abnormalities in this group suggests that, until the optimal dosing interval for vaginal use is determined, the preferred route of misoprostol administration might be oral.

Risk scoring, fetal fibronectin, and bacterial vaginosis to predict preterm delivery.

OBJECTIVE: To determine the value of markers for predicting spontaneous preterm birth. METHODS: One hundred forty asymptomatic gravidas were recruited from 20-24 weeks' gestation. Risk score was assessed, vaginal swabs were analyzed for bacterial vaginosis, and cervical and vaginal swab were tested for fetal fibronectin FDC-6, X18A4, and CAF. Univariate analysis was used to determine potential predictors (and combinations of predictors) of outcome. Multiple logistic regression was done to identify independent predictors of spontaneous preterm birth. Sensitivity, specificity, positive and negative predictive values; and odds and likelihood ratios were calculated for significant predictors. RESULTS: Predictors significantly associated with the primary outcome were preterm birth-risk score and vaginal fetal fibronection FDC-6 (logistic regression odds ratio [OR] 16.9 [95% confidence interval (CI) 3.1, 92.8]) and 8.0 ([95% CI 1.6, 38.2], respectively). Bacterial vaginosis, fetal fibronectin X18A4, fibronectin CAF, and cervical fetal fibronectin FDC-6 were not associated with spontaneous preterm birth; however, the statistical power to assess these variables was limited. The combination of positive preterm birth-risk score and vaginal fetal fibronectin FDC-6 had a sensitivity of 44.4%, specificity of 97.7%, positive predictive value of 57.1%, negative predictive value of 96.2%, and a significant likelihood ratio for a positive test of 19.4 (95% CI 5.1, 73.8). CONCLUSION: The combination of preterm birth-risk score and vaginal fetal fibronectin FDC-6 predicted spontaneous preterm birth. Intervention trials are required to determine whether a combination of screening tests will reduce rates of spontaneous preterm birth.

Neonatal outcomes with placenta previa.

OBJECTIVE: To identify neonatal complications associated with placenta previa. METHODS: This was a population-based, retrospective cohort study involving all singleton deliveries in Nova Scotia from 1988 to 1995. The study group consisted of all completed singleton pregnancies complicated by placenta previa; all other singleton pregnancies were considered controls. Patient information was collected from the Nova Scotia Atlee perinatal database. Neonatal complications were evaluated while controlling for potential confounders. The data were analyzed using chi2, Fisher exact test, and multiple logistic regression. RESULTS: Among 92,983 pregnancies delivered during the study period, 305 cases of placenta previa were identified (0.33%). After controlling for potential confounders, neonatal complications significantly associated with placenta previa included major congenital anomalies (odds ratio [OR] 2.48), respiratory distress syndrome (OR 4.94), and anemia (OR 2.65). The perinatal mortality rate associated with placenta previa was 2.30% (compared with 0.78% in controls) and was explained by gestational age at delivery, occurrence of congenital anomalies, and maternal age. Although there was a higher rate of preterm births in the placenta previa group (46.56% versus 7.27%), there was no difference in birth weights between groups after controlling for gestational age at delivery. CONCLUSION: Neonatal complications of placenta previa included preterm birth, congenital anomalies, respiratory distress syndrome, and anemia. There was no increased occurrence of fetal growth restriction.

Randomized comparison of oral misoprostol and oxytocin for labor induction in term prelabor membrane rupture.

OBJECTIVES: To compare labor induction intervals between oral misoprostol and intravenous oxytocin in women who present at term with premature rupture of membranes. METHODS: One hundred eight women were randomly assigned to misoprostol 50 microg orally every 4 hours as needed or intravenous oxytocin. The primary outcome measure was time from induction to vaginal delivery. Sample size was calculated using a two-tailed alpha of 0.05 and power of 80%. RESULTS: Baseline demographic data, including maternal age, gestation, parity, Bishop score, birth weight, and group B streptococcal status, were similar. The mean time +/-standard deviation to vaginal birth with oral misoprostol was 720+/-382 minutes compared with 501+/-389 minutes with oxytocin (P = .007). The durations of the first, second, and third stages of labor were similar. There were no differences in maternal secondary outcomes, including cesarean birth (eight and seven, respectively), infection, maternal satisfaction with labor, epidural use, perineal trauma, manual placental removal, or gastrointestinal side effects. Neonatal outcomes including cord pH, Apgar scores, infection, and admission to neonatal intensive care unit were not different. CONCLUSION: Although labor induction with oral misoprostol was effective, oxytocin resulted in a shorter induction-to-delivery interval. Active labor intervals and other maternal and neonatal outcomes were similar.

Surgical experience with hyperparathyroidism.

This is a retrospective analytic review of 208 patients with hyperparathyroidism studied and treated at Vanderbilt University Hospital from 1935 to 1980. Follow-up in these patients has been completed to date or to death in a great majority of patients. Results indicate the value of excision of isolated adenomas and of subtotal parathyroidectomy for primary and secondary hyperplasia.