Faculty Bibliography

OBJECTIVE:This study was performed to evaluate the effect of pre-pregnancy body mass index (BMI) on the success of cerclage. MATERIALS AND METHODS/METHODS:A retrospective cohort study of women who had a history-indicated (HIC) or ultrasound-indicated cerclage (UIC) placed between 1994 and 2011. Based on pre-pregnancy BMI (World Health Organization criteria), three cohorts were defined: normal/overweight (BMI: 20.0-29.9 kg/m(2)), obese class I/II (BMI: 30.0-39.9 kg/m(2)) and obese class III (BMI ≥ 40.0 kg/m(2)). The primary outcome was spontaneous preterm birth (sPTB) <35 weeks. The secondary outcomes included but were not limited to gestational age of delivery, sPTB <37, <32 and <28 weeks, preterm premature rupture of membranes and birth weight. RESULTS:375 women were included for analysis. Demographics were similar in the three BMI categories, except black race (p = 0.01). The rates of sPTB <35 weeks were similar between each cohort: 24.3%, 23.0% and 27.7%, respectively (p = 0.81). BMI was not a predictor of any of the secondary outcomes. A HIC was placed in 47.2% and an UIC was placed in 52.8% women. Both unadjusted and adjusted analysis showed no significant difference in sPTB <35 weeks between BMI categories overall or by cerclage type (HIC or UIC). CONCLUSIONS:Pre-pregnancy BMI is not a significant predictor of sPTB <35 weeks in women with HIC or UIC.

INTRODUCTION/BACKGROUND:The indications of placement of cerclage have recently changed, and so it is important to evaluate how many women are undergoing this procedure. With the recent completion of clinical trials, it is plausible that obstetricians and perinatologists may have become more selective in terms of the best candidates for cerclage. MATERIAL AND METHODS/METHODS:We conducted a retrospective cohort study of women who underwent cerclage for prevention of preterm birth in the Division of Maternal and Fetal Medicine of Thomas Jefferson University Hospital (Philadelphia, USA) over a 16-year period, from 1998 to 2013. We included women with singleton gestations who had a history-indicated (HIC) or ultrasound-indicated cerclage (UIC). Physical examination-indicated cerclage and transabdominal cerclage were excluded. We planned to compare data before and after 2005. RESULTS:From 1998 to 2013, there were 33 353 deliveries, of which 16 871 occurred from 1998 to 2005 and 16 482 from 2006 to 2013. Of all deliveries, 328 women (1.0%) received HIC or UIC, and were therefore included in the analysis. Between 1998-2005 and 2006-2013 there were significant decreases in the overall rate of cerclage (1.4% to 0.6%; p < 0.001), as well as the rate of HIC (0.8% to 0.2%; p < 0.001) and UIC (0.6% to 0.3%; p < 0.001). CONCLUSIONS:During the last 16 years, the overall rate of HIC and UIC cerclage at Thomas Jefferson University Hospital significantly declined from 1.4% to 0.6%; significant decreases were seen for both HIC and UIC. The reason for the lower rate of cerclages may be the recently published evidence.

OBJECTIVE:To evaluate outcomes of women with prior ultrasound-indicated cerclage, who in their subsequent pregnancy were either followed by transvaginal ultrasound cervical length screening or received a planned history-indicated cerclage. METHODS:Multicenter cohort study of singleton gestations with a prior ultrasound-indicated cerclage performed from 1994 to 2014. We evaluated three pregnancies in the study participants: first pregnancy with prior spontaneous preterm birth at less than 37 weeks of gestation; second pregnancy with ultrasound-indicated cerclage for cervical length 25 mm or less; and the third index pregnancy managed with either transvaginal ultrasound cervical length screening with ultrasound-indicated cerclage for cervical length 25 mm or less or planned history-indicated cerclage. The primary outcome was incidence of spontaneous preterm birth at less than 37 weeks of gestation. We planned a subgroup analysis for women who delivered at less than 32 weeks of gestation compared with 32 weeks of gestation or greater in their prior ultrasound-indicated cerclage pregnancy. RESULTS:Of 102 singleton gestations included, 38 (37.3%) were followed with transvaginal ultrasound cervical length screening and 64 (62.7%) underwent history-indicated cerclage. Of 38 women in the transvaginal ultrasound group, 18 (47.4%) underwent ultrasound-indicated cerclage for cervical length 25 mm or less. After adjusting for confounders, the rate of spontaneous preterm birth at less than 37 weeks of gestation was similar between transvaginal ultrasound cervical length screening and history-indicated cerclage groups (36.8% compared with 43.8%; adjusted odds ratio 0.77, 95% confidence interval 0.47-1.45). Secondary outcomes were also similar in both groups. All women (n=7) who delivered at less than 32 weeks of gestation in their prior pregnancy and subsequently had transvaginal ultrasound screening received ultrasound-indicated cerclage in the index pregnancy compared with only 35.5% of women who delivered at 32 weeks of gestation or greater in their prior pregnancy. CONCLUSION/CONCLUSIONS:Women with prior ultrasound-indicated cerclage have similar outcomes if they receive either transvaginal ultrasound cervical length screening with ultrasound-indicated cerclage for cervical length 25 mm or less or planned history-indicated cerclage in the subsequent pregnancy. Less than 50% of the transvaginal ultrasound cervical length screening group require a repeat ultrasound-indicated cerclage in the subsequent pregnancy. LEVEL OF EVIDENCE/METHODS:II.

OBJECTIVE:We sought to evaluate the efficacy of maintenance tocolysis with vaginal progesterone compared to control (placebo or no treatment) in singleton gestations with arrested preterm labor (PTL) in a metaanalysis of randomized controlled trials. STUDY DESIGN/METHODS:Searches were performed in MEDLINE, OVID, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials with the use of a combination of key words and text words related to "progesterone," "tocolysis," and "preterm labor" from 1966 through November 2014. We included all randomized trials of singleton gestations that had arrested PTL and then were randomized to maintenance tocolysis treatment with either vaginal progesterone or control (either placebo or no treatment). All published randomized studies on progesterone tocolysis were carefully reviewed. Exclusion criteria included maintenance tocolysis in women with preterm premature rupture of membrane, maintenance tocolysis with 17-alpha-hydroxyprogesterone caproate, and maintenance tocolysis with oral progesterone. The summary measures were reported as relative risks (RRs) with 95% confidence interval (CI). The primary outcome was preterm birth (PTB) <37 weeks. RESULTS:Five randomized trials, including 441 singleton gestations, were analyzed. Women who received vaginal progesterone maintenance tocolysis for arrested PTL had a significantly lower rate of PTB <37 weeks (42% vs 58%; RR, 0.71; 95% CI, 0.57-0.90; 3 trials, 298 women). Women who received vaginal progesterone had significantly longer latency (mean difference 13.80 days; 95% CI, 3.97-23.63; 4 trials, 368 women), later gestational age at delivery (mean difference 1.29 weeks; 95% CI, 0.43-2.15; 4 trials, 368 women), lower rate of recurrent PTL (24% vs 46%; RR, 0.51; 95% CI, 0.31-0.84; 2 trials, 122 women), and lower rate of neonatal sepsis (2% vs 7%; RR, 0.34; 95% CI, 0.12-0.98; 4 trials, 368 women). CONCLUSION/CONCLUSIONS:Maintenance tocolysis with vaginal progesterone is associated with prevention of PTB, significant prolongation of pregnancy, and lower neonatal sepsis. However, given the frequent lack of blinding and the generally poor quality of the trials, we do not currently suggest a change in clinical care of women with arrested PTL. We suggest instead well-designed placebo-controlled randomized trials to confirm the findings of our metaanalysis.

We sought to evaluate the efficacy of maintenance tocolysis with 17-alpha-hydroxyprogesterone caproate (17P) compared to control (either placebo or no treatment) in singleton gestations with arrested preterm labor (PTL), in a metaanalysis of randomized trials. Electronic databases (MEDLINE, OVID, Scopus, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials) were searched from 1966 through July 2014. Key words included "progesterone," "tocolysis," "preterm labor," and "17-alpha-hydroxyprogesterone caproate." We performed a metaanalysis of randomized trials of singleton gestations with arrested PTL and treated with maintenance tocolysis with either 17P or control. Primary outcome was preterm birth (PTB) <37 weeks. This metaanalysis was performed following the Preferred Reporting Items for Systematic Reviews and Metaanalyses (PRISMA) statement. The protocol was registered with PROSPERO (registration no: CRD42014013473). Five randomized trials met inclusion criteria, including 426 women. Women with a singleton gestation who received 17P maintenance tocolysis for arrested PTL had a similar rate of PTB <37 weeks (42% vs 51%; relative risk [RR], 0.78; 95% confidence intervals [CI], 0.50-1.22) and PTB <34 weeks (25% vs 34%; RR, 0.60; 95% CI, 0.28-1.12) compared to controls. Women who received 17P had significantly later gestational age at delivery (mean difference, 2.28 weeks; 95% CI, 1.46-13.51), longer latency (mean difference, 8.36 days; 95% CI, 3.20-13.51), and higher birthweight (mean difference, 224.30 g; 95% CI, 70.81-377.74) as compared to controls. Other secondary outcomes including incidences of recurrent PTL, neonatal death, admission to neonatal intensive care unit, neonatal respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, and neonatal sepsis were similar in both groups. Maintenance tocolysis with 17P after arrested PTL is not associated with prevention of PTB compared to placebo or no treatment in a metaanalysis of the available randomized trials. As 17P for maintenance tocolysis is associated with a significant prolongation of pregnancy, and significantly higher birthweight, further research is suggested.

Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. With research efforts, the rate of PTB decreased to 11.4% in 2013. Transvaginal ultrasound (TVU) cervical length (CL) screening predicts PTB. In asymptomatic singletons without prior spontaneous PTB (sPTB), TVU CL screening should be done. If the cervix is 20 mm or less, vaginal progesterone is indicated. In asymptomatic singletons with prior sPTB, serial CL screening is indicated. In multiple gestations, routine cervical screening is not indicated. In symptomatic women with preterm labor, TVU CL screening and fetal fibronectin testing is recommended.

Cervical cerclage is an obstetric procedure performed for prevention of prematurity. Cerclage was first introduced by Drs Shirodkar and McDonald in the mid-1950s for women with repeated second trimester losses and cervical changes in current pregnancy. Currently, cerclage placement is based on 3 common indications in singleton gestations, including history-indicated (prior multiple early preterm births or second trimester losses), ultrasound-indicated (cervical length <25 mm before 24-wk gestational age in women with prior spontaneous preterm birth) and physical examination-indicated (cervical dilation on manual or physical examination before 24 wk).

OBJECTIVE:To determine whether the acceleration/ejection time ratio of the fetal main pulmonary artery Doppler waveform (PATET) can accurately predict the results of fetal lung maturity testing in amniotic fluid. METHODS:We prospectively studied pregnant women attending our ultrasound unit for clinically indicated fetal lung maturity testing. An ultrasound examination that included measurement of the PATET was performed before the results of the amniocentesis were reported. The results of the PATET and the surfactant/albumin ratio were compared, and a receiver operating characteristic curve was used to determine the PATET cutoff with the optimal sensitivity and specificity for predicting surfactant/albumin ratio results. p < 0.05 was considered statistically significant. RESULTS:Forty-three patients were included in this study. The receiver operating characteristic curve demonstrated that a PATET cutoff of 0.3149 provided a specificity of 93% (95% CI 77-98%), a sensitivity of 73% (95% CI 48-89%), a negative predictive value of 87% (95% CI 70-95%), and a positive predictive value of 85% (95% CI 58-96%) for predicting immature surfactant/albumin ratio results. CONCLUSION/CONCLUSIONS:The PATET may provide a noninvasive means of determining fetal lung maturity with acceptable levels of sensitivity, specificity, and predictive values.

This study was performed to determine if cerclage height is associated with spontaneous preterm birth in patients with a history-indicated cerclage. We performed a retrospective cohort study of women with a history-indicated cerclage. Functional cervical length and the cerclage height (distance from cerclage to the external cervical os) were obtained. The cohort was grouped into thirds, based on cerclage height percentile. Our primary outcome was spontaneous preterm birth <35 weeks. There were 21 women in group 1 (cerclage height <10 mm), 53 in group 2 (cerclage height 10 to 19 mm), and 31 in group 3 (cerclage height ≥20 mm). The rates of spontaneous preterm birth <35 weeks were similar between each group: 24, 17, and 10%, respectively ( P = 0.38). Cerclage height is not associated with a reduction in spontaneous preterm birth for women with a history-indicated cerclage. The association between longer cerclage height and decrease in preterm birth was nonsignificant possibly due to the small sample size.