Kate Pettit

Ultrasound estimation of fetal weight in small for gestational age pregnancies

Objective. Approximately half of small for gestational age (SGA) cases are due to maternal or fetal pathology, and may result in significant neonatal morbidity and mortality. The estimated fetal weight (EFW) measurement is the cornerstone of ultrasonographic findings when diagnosing and managing SGA pregnancies. Our objective was to determine the ultrasound accuracy of EFW in SGA pregnancies. Methods. A retrospective chart review was performed of all pregnancies complicated by SGA from a single institution (Stanford University) over a 2-year-period (2004–2006). SGA was defined as EFW ≤ 10%. 98 neonates whose last ultrasound for EFW occurred within 7 days of delivery were included in the study. The absolute differences between the EFW and birthweight (BW) were analyzed, and the absolute percent errors were calculated as (EFW − BW)/BW ×  100. The mean absolute differences and mean absolute percent errors were analyzed across all gestational ages (GA) and EFWs using one-way analysis of variance. Results. The mean absolute percent error for the entire cohort was 8.7% (±6.3%). There was no statistically significant difference in the mean absolute percent error across all GAs (<32 weeks, 32–36 weeks, >36 weeks), and EFWs (<1500 g, 1500–2000 g, >2000 g). Conclusion. Ultrasound measurement of EFW in SGA pregnancies is consistent across all GAs and EFW measurements.

The association of inadequate mid-pregnancy weight gain and preterm birth in twin pregnancies.

Objective:To determine whether inadequate gestational weight gain in the second trimester in twin pregnancies is associated with an increased risk of preterm birth (PTB) at <32 weeks.Study Design:Retrospective cohort study including 489 twin pregnancies delivered between 2001 and 2013. Rates of weight gain at different gestational ages were compared with Institute of Medicine guidelines.Result:An inadequate rate of weight gain at <20 weeks was not associated with PTB. Patients with inadequate rates of weight gain at 20 to 28 weeks had a higher risk of PTB at <32 weeks (37.6%) compared to those with adequate weight gain (15.2%) (P<0.001). In multivariate analysis, women with inadequate weight gain at 20 to 28 weeks were 2.8 times more likely to deliver at <32 weeks (95% confidence interval 1.65 to 4.81).Conclusion:Inadequate gestational weight gain at 20 to 28 weeks in twin pregnancies was the strongest predictor of PTB at <32 weeks. This represents an optimal time for interventions to improve weight gain and potentially decrease rates of PTB.

The association of antenatal corticosteroids with neonatal hypoglycemia and hyperbilirubinemia

Abstract Objective: While antenatal corticosteroids reduce the risk of neonatal morbidity and mortality, perhaps the maternal hyperglycemia they produce has other neonatal effects. Thus, we sought to examine the association between antenatal betamethasone exposure and neonatal hypoglycemia and hyperbilirubinemia. Methods: We designed a retrospective cohort study of all preterm deliveries from 32 to 37 weeks of gestation at a single university hospital from 1990 to 2007. Data were collected on antenatal betamethasone administration and the neonatal outcomes. Univariable, multivariable and stratified analyses were conducted. Results: Of 6675 preterm deliveries, significantly higher rates of neonatal hypoglycemia (5.7% versus 4.2%, p < 0.05) and hyperbilirubinemia (45.9% versus 24.1%, p < 0.05) were observed in neonates exposed to antenatal betamethasone. Controlling for potential confounders including gestational age, these findings persisted with betamethasone-exposed neonates 1.6 times more likely to have hypoglycemia (aOR 1.60, 95% CI 1.24–2.07) and 3.2 times more likely to have hyperbilirubinemia (aOR 3.23, 95% CI 2.92–3.58). Conclusions: Antenatal betamethasone was associated with neonatal hypoglycemia and hyperbilirubinemia. Further work to determine whether this association is related to maternal hyperglycemia should be conducted, given this could be addressed with strict maternal glycemic control during betamethasone administration.

Noninvasive prenatal testing: a replacement for chorionic villus sampling and amniocentesis for advanced maternal age?

INTRODUCTION: Our objective was to assess the effect of the availability of noninvasive prenatal testing using circulating cell-free fetal DNA on the uptake of routine chorionic villus sampling (CVS) or genetic amniocentesis for advanced maternal age greater than or equal to 35 years. METHODS: Retrospective cohort study of all women who chose noninvasive prenatal testing from May to December 2012 at the University of California San Diego Fetal Care and Genetics Center. Indications for noninvasive prenatal testing were advanced maternal age, high-risk aneuploidy screening, abnormal ultrasound findings, and a family history of aneuploidy. Data were collected by chart review. The numbers of CVS and amniocenteses performed from May to December 2012 were recorded. RESULTS: Two hundred six patients chose noninvasive prenatal testing and 155 (75%) had advanced maternal age. The remaining 51 had abnormal aneuploidy screening, ultrasound findings, or both suggestive of aneuploidy. For 70 women (34%), advanced maternal age alone was the indication for noninvasive prenatal testing. The mean age of this group was 37.7±2.5 years (range 35–44 years). One of the tests done for advanced maternal age alone was positive for trisomy 21, which was confirmed by CVS. The remaining 69 women (98.6%) declined invasive testing. None of these 69 neonates had abnormal karyotypes. CONCLUSIONS: In our practice, women are choosing noninvasive prenatal testing rather than undergoing invasive testing for the sole indication of advanced maternal age. Although detection of aneuploidy with noninvasive prenatal testing is not 100%, patients with reassuring serum aneuploidy screening and normal ultrasound findings appear to favor a small risk of missing a diagnosis of aneuploidy over the risk of procedure-related pregnancy loss.

Evaluation of Fetal First and Second Cervical Vertebrae: Normal or Abnormal?

To use 3‐dimensional sonographic volumes to evaluate the variable appearance of the normal fetal cervical spine and craniocervical junction, which if unrecognized may lead to misdiagnosis of malalignment at the first and second cervical vertebrae (C1 and C2).

Maternal and neonatal outcomes in women with twin pregnancies with excessive gestational weight gain

Abstract Objective: To determine if an excessive rate of gestational weight gain (GWG) in twin pregnancies is associated with adverse obstetric outcomes. Methods: Retrospective cohort study of twin pregnancies delivered at the University of California, San Diego 2001–2014. Women were included if they had adequate or excessive rates of GWG as determined by Institute of Medicine guidelines. Demographic and outcome variables were collected by chart review. Results: Four hundred and eighty-nine twin pregnancies met inclusion criteria. Of which, 40.5% had adequate rates of GWG and 41.5% had excessive rates of GWG. The rates of preterm birth and gestational diabetes were similar between the two groups. Gestational hypertension and preeclampsia were more common in women with excessive GWG (37.9% versus 19.7%; p < 0.01). This finding persisted in multivariate analysis. The mean birth weight percentiles were higher in the excessive GWG group and these women were also less likely to have an infant with a birth weight <10th percentile (21.4% versus 35.9%, p < 0.01). Conclusions: Excessive GWG is associated with a higher risk for gestational hypertension and preeclampsia, but no other adverse perinatal outcomes. Infants born to mothers with excessive GWG are less likely to be small for gestational age than those born to women with adequate GWG.

Placental Sonolucencies in the First Trimester: Incidence and Clinical Significance.

Objectives The aims of this study were to determine the incidence of placental sonolucencies on first-trimester screening sonograms in a general obstetric population and assess whether these findings are associated with adverse obstetric outcomes. Methods A retrospective cohort analysis of 201 pregnant patients screened at a high-risk prenatal diagnostic center was conducted with first-trimester cine clips reviewed by 2 radiologists. Placental sonolucencies were defined as intraplacental anechoic or heterogeneous areas 0.7 cm or greater. Obstetric and neonatal outcomes were collected by chart review. Results Placental sonolucencies 0.7 cm or greater were seen in 45 (22.4%) of first-trimester ultrasound examinations. The ultrasonographic presence of a placenta previa, marginal sinus, and subchorionic hemorrhage was not more common in those with placental sonolucencies 0.7 cm or greater (P > 0.05). Sonolucencies were not associated with prior cesarean deliveries (P > 0.05). Both the groups with and without sonolucencies 0.7 cm or greater had similar rates of antepartum hemorrhage, preeclampsia, preterm delivery, cesarean delivery, postpartum hemorrhage, and delivery of small-for-gestational-age infants. One placenta accreta and no fetal demises occurred in the study population. Conclusions Placental sonolucencies detected on first-trimester screening sonograms in the general obstetric population are not predictive of poor obstetric outcomes.

Rates of Gestational Weight Gain and Postpartum Weight Retention in Term Twin Pregnancies

INTRODUCTION: Our objective was to characterize gestational weight gain and postpartum weight retention in term twin pregnancies by body mass index (BMI) and trimester. METHODS: Retrospective cohort study including all term twin pregnancies at the University of California, San Diego Medical Center 2009–2013. Adequate gestational weight gain was determined by the 2009 Institute of Medicine guidelines for twin pregnancies. Students t test and the &khgr;2 test were used for analyses. RESULTS: Fifty-nine term twin pregnancies met inclusion criteria. Mean gestational weight gain for the cohort was 16.6±5.1 kg. According to Institute of Medicine guidelines, 15% had insufficient, 39% had sufficient, and 46% had excessive gestational weight gain. There were no differences in total gestational weight gain by chorionicity or BMI. The mean rates of gestational weight gain were 0.5±0.2 kg per week until 20 weeks of gestation, 0.7±0.3 kg per week at 20–28 weeks of gestation, and 0.7±0.4 kg per week from 28 weeks of gestation to term. Comparing rates of gestational weight gain between BMI groups, there were significant differences in rates of gestational weight gain before 20 weeks of gestation but no differences at 20–28 weeks of gestation and from 28 weeks of gestation to term. At the postpartum visit, 74% of normal, 93% of overweight, and 33% of obese women were within 5 kg of their first pregnancy weight (P=.02). CONCLUSIONS: The majority of twin pregnancies have sufficient gestational weight gain during their pregnancies and 46% exceed guidelines. Contrary to singletons, pregravid BMI does not adversely affect gestational weight gain. Beyond 20 weeks of gestation, gestational weight gain for women of different BMI groups occurs at similar rates. However, obesity is associated with a higher risk of postpartum weight retention in twin pregnancies.

The Utilization of Antenatal Late Preterm Steroids at a Tertiary Care Academic Medical Center [24I]

INTRODUCTION:The purpose of this study was to examine the utilization of antenatal late preterm steroids (ALPS) at a single institution following publication of recent evidence suggesting neonatal benefits in the late preterm period.METHODS:A retrospective cohort study was performed including all pa

Targeted delivery at 34 versus 35 weeks in women with preterm prelabor rupture of membranes.

Abstract Objective: To compare planned delivery at 34 versus 35 weeks for women with preterm prelabor rupture of membranes (PPROM). Materials and methods: We performed a retrospective cohort study of singleton pregnancies with PPROM after 24 weeks delivered from 2006 to 2014. In 2009, an institutional practice change established 35 weeks as the target gestational age before induction of labor was initiated after PPROM. Demographic and outcome measures were compared for two cohorts: women delivered 2006–2008 – target 34 weeks (T34) and women delivered 2009–2014 – target 35 weeks (T35). The primary outcome was neonatal intensive care unit (NICU) admission. Results: Of the 382 women with PPROM, 153 (40%) comprized the T34 cohort and 229 (60%) comprized the T35 cohort. Demographic characteristics were similar between groups. There were no differences between groups in gestational age at PPROM (31.0 ± 3.3 weeks versus 31.2 ± 3.1 weeks; p = .50) or maternal complications. The mean gestational age at delivery was earlier in the T34 group (31.8 ± 3.2 weeks versus 32.4 ± 2.7 weeks; p = .04). The median predelivery maternal length of stay (LOS) was 1 day longer in the T35 group (p = .03); the total and postpartum LOS were similar between groups (p > .05). There were no differences in the rate of NICU admission (T34 89.5% versus T35 92.1%; p = .38) or median neonatal LOS (T34 14 days versus T35 17 days; p = .15). In those patients who reached their target gestational age, both maternal predelivery LOS and total LOS were longer in the T35 group (p > .05). The frequency of NICU admission in those reaching their target gestational age was similar between groups (T34 83.37% versus T35 76.19%; p = .46). Conclusions: A 35-week target for delivery timing for women with PPROM does not decrease NICU admissions or neonatal LOS. This institutional change increased maternal predelivery LOS, but did not increase maternal or neonatal complications.