Faculty Bibliography

OBJECTIVES:Monoamniotic twin pregnancies are at increased risk of perinatal complications, primarily owing to the risk of cord entanglement. There is no recommendation on whether such pregnancies should be managed in hospital or can be safely managed in an outpatient setting, and the timing of planned delivery is also a subject of debate. The aim of this study was to compare the perinatal outcomes of inpatient vs outpatient fetal surveillance approaches employed among 22 participating study centers, and to calculate the fetal and neonatal death rates according to gestational age, in non-anomalous monoamniotic twins from 26 weeks' gestation. METHODS:The MONOMONO study was a multinational cohort study of consecutive women with monochorionic monoamniotic twin pregnancies, who were referred to 22 university hospitals in Italy, the USA, the UK and Spain, from January 2010 to January 2017. Only non-anomalous uncomplicated monoamniotic twin pregnancies with two live fetuses at 26 + 0 weeks' gestation were included in the study. In 10 of the centers, monoamniotic twins were managed routinely as inpatients, whereas in the other 12 centers they were managed routinely as outpatients. The primary outcome was intrauterine fetal death. We also planned to assess fetal and neonatal death rates according to gestational age per 1-week interval. Outcomes are presented as odds ratio (OR) with 95% CIs. The main outcome was analyzed using both standard logistic regression analysis, in which each fetus was treated as an independent unit, and a generalized mixed-model approach, with each twin pair treated as a cluster unit, considering that the outcome for a twin is not independent of that of its cotwin. RESULTS:195 consecutive pregnant women with a non-anomalous uncomplicated monoamniotic twin gestation (390 fetuses) were included. Of these, 75 (38.5%) were managed as inpatients and 120 (61.5%) as outpatients. The overall perinatal loss rate was 10.8% (42/390) with a peak fetal death rate of 4.3% (15/348) occurring at 29 weeks' gestation. There was no significant difference in mean gestational age at delivery (31 weeks), birth weight (∼1.6 kg), or emergency delivery rate between the inpatient and outpatient surveillance groups. Based on generalized mixed-model analysis, there was no statistically significant difference in fetal death rates between inpatient management commencing from around 26 weeks compared with outpatient surveillance protocols from 30 weeks (3.3% vs 10.8%; adjusted OR 0.21 (95% CI, 0.04-1.17)). Maternal length of stay in the hospital was 42.1 days in the inpatient group, and 7.4 days in the outpatient group (mean difference 34.70 days (95% CI, 31.36-38.04 days). From 32 + 0 to 36 + 6 weeks, no fetal or neonatal death in either group was recorded. 46 fetuses were delivered after 34 + 0 weeks, and none of them died in utero or within the first 28 days postpartum. CONCLUSION:In uncomplicated monoamniotic twins, inpatient surveillance is associated with similar fetal mortality as outpatient management. After 31 + 6 weeks, and up to 36 + 6 weeks, there were no intrauterine fetal deaths or neonatal deaths. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

OBJECTIVE:To evaluate whether second-trimester cervical length (CL) is associated with induction of labor (IOL) outcomes. METHODS:Retrospective cohort study of nulliparous singletons undergoing CL screening at 18 0/7-23 6/7 weeks from 1/1/2012 to 12/31/2013. Women induced at term (≥37 weeks) were included. Primary outcome was vaginal delivery (VD) within 24 h. The effect of CL on outcomes was assessed by incidence across CL quartiles and a receiver operating characteristics (ROC) curve. Odds ratios (OR) were adjusted (aOR) for confounders. RESULTS:Two-hundred-and-sixty-eight women were included. Aside from a difference in incidence of prior cervical surgery between CL quartiles (p <. 02), other characteristics were similar. Ninety-two women (35%) had a VD within 24 h (versus a CD or VD >24 h). A longer a CL was associated with a decreased likelihood of a VD within 24 h with aORs of the third and fourth quartiles of 0.35 (0.16-0.75) and 0.43 (0.21-0.90), respectively, compared to the first quartile. A CL >40 mm was predictive of not having a VD within 24 h with a sensitivity of 56%, specificity of 58% and a positive predictive value of 72%. CONCLUSION/CONCLUSIONS:A second-trimester CL >40 mm is associated with a decreased likelihood of VD within 24 h in an IOL.

OBJECTIVE:To determine whether second trimester transvaginal ultrasound cervical length (CL) is associated with prolonged pregnancy (≥41 0/7 weeks) in nulliparous women who reach term (≥37 weeks) with a planned vaginal delivery. METHODS:Retrospective cohort of nulliparous singletons 18 0/7-23 6/7 weeks gestation undergoing CL screening from 1/1/12 to 12/31/13. Women who delivered at term with spontaneous labor or reached 41 weeks were included. Primary outcome was incidence of prolonged pregnancy. Risk of prolonged pregnancy was assessed by CL quartile using odds ratio, adjusted for confounders (aOR) and a receiver operating characteristic (ROC) curve. RESULTS:722 women were included, among them 171 (24%) had a prolonged pregnancy. There was a significant difference in BMI and race across CL quartiles. The aOR of having a prolonged pregnancy with CL in quartiles 2, 3, and 4 versus quartile 1 were 2.14(1.27-3.62), 2.72(1.59-4.65), and 1.69(1.02-3.03), respectively. CL ≥ 37 mm (beyond first quartile) was associated with a two-fold increased risk of prolonged pregnancy versus CL < 37 mm, (27% vs 15%, p < 0.01, aOR 2.17 (1.38-3.41)). ROC curve did not identify a CL cutoff that was predictive of prolonged pregnancy (AUC 0.544, p = 0.079). CONCLUSIONS:Although a longer second trimester CL is associated with an increased risk for prolonged pregnancy, it is not predictive.

The diagnosis of cervical insufficiency can be made in women with or without prior pregnancy losses. Cervical insufficiency has been defined by transvaginal ultrasound cervical length <25 mm before 24 weeks in women with prior pregnancy losses or preterm births at 14 to 36 weeks, or by cervical changes detected on physical examination before 24 weeks of gestation.

Cervical cerclage is a surgical procedure to prevent preterm birth. There are currently 3 main indications, based on either history, ultrasound, or physical exam changes.

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.

OBJECTIVE: We evaluated pessary for dilated cervix and exposed membranes for prolonging pregnancy compared to cerclage or expectant management. METHODS: Multicenter retrospective cohort study of women, 15-24 weeks, singleton pregnancies, dilated cervix >/=2 cm and exposed membranes. Women received pessary, cerclage or expectant management. Primary outcome was gestational age (GA) at delivery. Secondary outcomes were time until delivery, preterm premature rupture of membranes (PPROM) and neonatal survival. RESULTS: About 112 women met study criteria; 9 - pessary, 85 - cerclage and 18 - expectant management. Mean GA at delivery was 22.9 +/- 4.5 weeks with pessary, 29.2 +/- 7.5 weeks with cerclage and 25.6 +/- 6.7 weeks with expectant management (p = 0.015). Time until delivery was 16.1 +/- 18.9 days in the pessary group, 61.7 +/- 48.2 days in the cerclage group and 26.8 +/- 33.4 days in the expectant group (p < 0.001). PPROM occurred less frequently and neonatal survival increased in women with cerclage. There was a significant difference in all the perinatal outcomes with cerclage compared with either pessary or expectant management. CONCLUSIONS: Perinatal outcomes with pessary were not superior to expectant management in women with dilated cervix with exposed membranes in the second trimester in this small retrospective cohort.

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.

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.