Anju Suhag

Intrauterine Growth Restriction (IUGR): Etiology and Diagnosis

Intrauterine growth restriction (IUGR) is associated with perinatal morbidity and mortality. IUGR is defined as fetus that fails to achieve his growth potential. Antenatal small for gestational age (SGA) is defined as fetus with weight <10th percentile. IUGR and SGA are commonly used interchangeably. The identification of IUGR is important. IUGR identification begins with assessment of risk factor(s), and the diagnosis is made by ultrasound using biometry when this confirms an estimated fetal weight (EFW) of <10th percentile. The common risk factors include maternal causes (hypertension, diabetes, cardiopulmonary disease, anemia, malnutrition, smoking, drug use), fetal causes (genetic disease including aneuploidy, congenital malformations, fetal infection, multiple pregnancies), and placental causes (placental insufficiency, placental infarction, placental mosaicism). Intrauterine growth determines the perinatal, postnatal, and adult life development. IUGR is associated with increased risk of development in adult life of metabolic diseases including but not limited to hypertension, diabetes, obesity, dyslipidemia, and the metabolic syndrome.

Is Cerclage Height Associated with the Incidence of Preterm Birth in Women with a History-Indicated Cerclage?

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.

Prior Ultrasound-Indicated Cerclage: Comparison of Cervical Length Screening or History-Indicated Cerclage in the Next Pregnancy.

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: 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: II

Predicting Fetal Lung Maturity Using the Fetal Pulmonary Artery Doppler Wave Acceleration/Ejection Time Ratio

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: The PATET may provide a noninvasive means of determining fetal lung maturity with acceptable levels of sensitivity, specificity, and predictive values.

Interval to spontaneous delivery after elective removal of cerclage

OBJECTIVE The purpose of this study was to estimate the time interval between elective cerclage removal and spontaneous delivery. METHODS Singleton pregnancies with McDonald cerclage were evaluated for the interval between elective cerclage removal (36-37 weeks) and spontaneous delivery. We also compared spontaneous delivery within 48 hours after cerclage removal between women with ultrasound-indicated vs history-indicated cerclage. RESULTS We identified 141 women with elective cerclage removal. The mean interval between removal and delivery was 14 days. Only 11% of women delivered within 48 hours. Women with ultrasound-indicated cerclage were more likely to deliver within 48 hours, compared with women with history-indicated cerclage (odds ratio, 5.14; 95% confidence interval, 1.10-24.05). CONCLUSION The mean interval between elective cerclage removal and spontaneous delivery is 14 days. Women with cerclage who achieved 36-37 weeks should be counseled that their chance of spontaneous delivery within 48 hours after elective cerclage removal is only 11%.

Short Cervical Length Dilemma

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.

Trends in cerclage use

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.

Pessary versus cerclage versus expectant management for cervical dilation with visible membranes in the second trimester

Abstract 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.

What Is the Optimal Gestational Age for History-Indicated Cerclage Placement?

We estimated the optimal gestational age for placement of a history-indicated cerclage in a retrospective cohort study of pregnancies during the period between 1994 to 2007. Pregnancies were divided into two groups: group 1, cerclage <14 weeks (N = 83), and group 2, cerclage >or=14 weeks (N = 59). The primary outcome was spontaneous preterm birth (SPTB) <35 weeks. Parametric and nonparametric tests were performed where appropriate. One hundred forty-two pregnancies by 130 women were included. Demographic characteristics were similar between groups. The median gestational age at cerclage was 12 weeks (group 1) and 15 weeks (group 2). There was no difference in the primary outcome, incidence of SPTB <35 weeks (17% versus 20%; P = 0.59) between groups 1 and 2, respectively. Likewise, the secondary outcomes, mean gestational age at birth (38 versus 37 weeks; P = 0.96), incidence of low birth weight (28% versus 23%; P = 0.50), and the incidence of preterm premature rupture of membranes (17% versus 18%; P = 0.89) were similar between groups. No other gestational age cutoff was predictive of SPTB <35 weeks using a receiver operator characteristic curve (13 to 17 weeks; area = 0.52; P = 0.64). Gestational age of history-indicated cerclage placement was not associated with a significant effect on preterm birth in high-risk women. The optimal gestational age for placement of a history-indicated cerclage is probably 12 to 14 weeks, after screening for fetal anomalies and aneuploidy.

Pre-pregnancy body mass index (BMI) and cerclage success

Abstract Objective: This study was performed to evaluate the effect of pre-pregnancy body mass index (BMI) on the success of cerclage. Materials and 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/m2), obese class I/II (BMI: 30.0–39.9 kg/m2) and obese class III (BMI ≥ 40.0 kg/m2). 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.