Abstract Introduction Fetal growth restriction (FGR) is associated with an increased risk of neonatal morbidity and mortality. Current diagnostic criteria for FGR do not discriminate between constitutionally small and pathologically restricted fetuses. Following FGR diagnosis, umbilical artery (UA) Doppler is utilized to monitor fetal well‐being, but its limitations have increased interest in investigating growth velocity as an adjunctive tool. The objective of this study is to compare the predictive ability of UA Doppler studies and growth velocity for adverse neonatal outcomes in growth‐restricted fetuses. Methods This is a secondary analysis of a cohort of pregnancies delivered in a single healthcare network from August 2017 to December 2022, diagnosed antenatally with FGR. The cohort was restricted to those with baseline estimated fetal weight (EFW) between the 3rd and 50th percentiles. All subjects had growth velocity measured (defined as EFW percentile change per week between baseline and subsequent ultrasound). The primary outcome was a composite of neonatal morbidity (neonatal intensive care unit [NICU] admission, low 5‐min Appearance, Pulse, Grimace, Activity, Respiration score [<7], intraventricular hemorrhage, necrotizing enterocolitis, or metabolic acidosis) and severe adverse perinatal events (stillbirth or neonatal death, hypoxic ischemic encephalopathy, mechanical ventilation, or severe metabolic acidosis [pH < 7.0]). Neonatal morbidity and severe adverse perinatal events were analyzed separately as secondary outcomes. Independence between growth velocity and S/D ratio was evaluated. Univariate logistic regression models were then performed, with each outcome of interest as the dependent variable and S/D ratio and growth velocity as independent variables. Receiver operating characteristic (ROC) curves were generated to compare the performance of both tests. Results A total of 172 patients were included in the analysis. UA Doppler data were available for 165 patients, 15.3% of whom had S/D ratio >95th percentile; none demonstrated absent or reversed end‐diastolic flow. There was no correlation observed between S/D ratio percentile and growth velocity, suggesting independence. ROC analysis demonstrated that the discriminatory ability of growth velocity was higher across outcomes with areas under the curve (AUC) ranging from 0.65 to 0.69 while AUC for S/D ratio percentiles ranged from 0.51 to 0.53, approximating the performance of chance. Higher growth velocity was significantly associated with reduced odds of the composite outcome (odds ratio [OR], 0.79; 95% confidence interval [CI], 0.69–0.90), and neonatal morbidity (OR, 0.84; 95% CI, 0.73–0.95). S/D ratio percentile was not associated with these outcomes. Conclusion In pregnancies complicated by growth restriction with forward UA flow, growth velocity outperformed S/D ratio percentile in predicting adverse outcomes. The two tests were independent, indicating that growth velocity may reflect a component of fetal development not captured by UA Doppler. These results suggest that growth velocity could be used in addition to UA Doppler studies for fetal risk assessment, especially in fetuses with forward arterial flow.
Percentile-Based Fetal Growth Velocity as a Predictor of Adverse Neonatal Outcomes in Fetal Growth Restriction and Small-for-Gestational-Age Pregnancies
Background: Pregnancies complicated by fetal growth restriction are at increased risk of fetal demise and adverse neonatal outcomes. Distinguishing growth-restricted fetuses from constitutionally small ones remains challenging. Given the variability in current diagnostic criteria and the importance of identifying at-risk fetuses, fetal growth velocity has emerged as a predictor of adverse neonatal outcomes. Objective: To evaluate whether percentile-based fetal growth velocity, defined as change in estimated fetal weight percentile per week, predicts adverse neonatal outcomes in pregnancies affected by fetal growth restriction or small-for-gestational-age neonates. The primary aim was to determine the relationship between growth velocity and a composite of adverse neonatal outcomes. Study Design: This was a retrospective cohort study of pregnant patients 18 - 45 years old who delivered between August 2017 to December 2022 in a single healthcare system. Patients were excluded who had fewer than 2 ultrasounds after 16 weeks gestation, genetic or anatomic abnormalities, or a multiple gestation. Results: 300 patients met all inclusion criteria, and most patients (n=199) delivered at the tertiary care center. Three had an intrauterine fetal demise at a mean gestational age of 35w3d. 74 neonates were admitted to the NICU with a mean length of stay of 8.5 days; 29 required respiratory support. No neonatal deaths occurred. In fetuses with initial estimated fetal weight <3rd percentile (n=33), the probability of composite outcome was increased (50%, 95% CI 44.8-55.2) compared to those >50th percentile (5%, 95% CI 3.7-6.6). In the 3-10th and 10 - 50th percentile subgroups with decelerated growth, composite outcome rates were also increased (56.2% and 44.1%) compared to those with neutral or increased growth velocity. Conclusion: Percentile-based fetal growth velocity is a simple calculation that correlates with adverse neonatal outcomes regardless of initial estimated fetal weight. As fetal growth velocity decreased, our cohort saw increased rates of adverse outcomes. Change in EFW percentile normalizes for gestational age and allows ease of clinical interpretation. Decelerated growth identified fetuses at highest risk, suggesting growth velocity as a useful metric in routine surveillance.
Inferior Vena Cava Filter Placement in Pregnancy and the Postpartum Period: A Single-Center Experience
Abstract Guidelines recommend placement of inferior vena cava filters (IVCFs) in patients with acute proximal lower extremity deep vein thrombosis (DVT) and a contraindication to anticoagulation. IVCF placement during pregnancy or immediately postpartum presents technical challenges and is not extensively described in the existing literature. This study aimed to describe the use of IVCFs in the obstetric population along with outcomes related to filter placement. Retrospective chart review of all patients at Mayo Clinic from 2001 to 2020 with an IVCF at the time of conception or who underwent placement during pregnancy/postpartum. About 24 pregnancies in 23 women (mean age 26.3 years, range 18–41) were included: 5 (21%) with IVCF placement prior to pregnancy, 7 (29%) during pregnancy, and 12 (50%) during postpartum. IVCFs placed during pregnancy were frequently in the suprarenal position, in 5 (71%) cases. Meanwhile, 16 (94%) were deployed in an infrarenal position prior to pregnancy and postpartum. Complications included multiple attempts to remove the IVCF (n = 2), severe angulation (n = 4), embedded struts (n = 3), fracture (n = 1), and one case of cardiac tamponade (n = 1). Complications were more common when placement was performed prior to pregnancy or during pregnancy (2, 40% and 4, 57% respectively) versus postpartum (2, 17%). IVCF placement prior or during pregnancy/postpartum is uncommon and is associated with a high incidence of complications, although most did not fundamentally impact clinical outcomes. While IVCFs remain an option for clinicians treating pregnant and postpartum patients, these should be considered a last resource.
Safety and Efficacy of Inferior Vena Cava Filters in the Peri-Partum Period: Experiences at a Tertiary Care Facility
Background: Guidelines recommend placement of inferior vena cava (IVC) filters in patients with acute thrombotic episodes and a concurrent contraindication to anticoagulation, however filter placement during or immediately postpartum presents significant technical challenges. The use and complications of IVC filters in the peripartum period is poorly documented in current literature. Objective(s): To evaluate the use of and outcomes related to IVC filters in an obstetric population at a large tertiary care center. Study Design: Retrospective review of all patients at a tertiary academic medical center from 2001-2016 who either conceived with an IVC filter in place or underwent IVC filter placement during the antepartum or postpartum interval. Manual abstraction of each chart was performed, with data stored in a RedCap database. Results: A total of 24 patients were included in the final analysis: 5 with IVC filter placement prior to pregnancy, 7 with antepartum placement, and 12 with postpartum placement. One patient had multiple pregnancies during our study timeframe and was therefore included twice. The cohort of postpartum placement were the youngest mean age (23.7 years), had a higher number of IVC filters placed for polytrauma (n=4), and had the shortest time to removal (135.9 days). The vast majority (91.3%) of IVC filters placed during pregnancy were retrievable filters in the suprarenal position, while most deployed in an infrarenal position (83.3%) when placed prior to conception. Complications encountered included multiple attempts to remove IVC filter, severe angulation, embedded struts, fracture, and one case of cardiac tamponade during filter placement requiring emergent sternotomy and evacuation. Of the filters requiring multiple attempts for removal, in 1 patient (4%) it was unable to be removed despite multiple attempts and the filter was ultimately left in situ. Complications were more common when placement was performed prior to pregnancy or antepartum (40% and 57.1% respectively) versus postpartum (16.7%). From an obstetrical perspective, 1 patient (4%) required early preterm delivery due to preeclampsia; 1 maternal death occurred in a postpartum patient who experienced a massive pulmonary embolism and subsequently died despite emergent thrombectomy and IVC filter placement, and 1 neonatal death occurred due to congenital heart disease following periviable preterm delivery. Conclusion(s): In our study across 16 years at a large academic medical center we identified 23 patients who had an IVC filter placed prior to pregnancy or placed during the antepartum or postpartum periods. Data from our experience suggested a higher incidence of complications with preconceptual and antepartum placement, although the majority of these did not impact clinical outcomes. While not frequently needed, IVC filters remain an option for clinicians treating pregnant and postpartum patients but should be considered a last resource as they can lead to various complications.
Efficacy of Rubella Vaccination after Co-Inoculation with Rhogam
Congenital rubella syndrome is a constellation of birth defects that can have devastating consequences, impacting approximately 100,000 births worldwide each year. The incidence is much lower in countries that routinely vaccinate their population. In the US, postnatal immunization of susceptible women is an important epidemiological strategy for the prevention of rubella as the Center for Disease Control (CDC) does not recommend administering this vaccine during pregnancy due to its nature as a live attenuated virus vaccine. However, concerns that the co-administration of rubella vaccine with other immunoglobins (i.e., Rhogam) could compromise vaccine efficacy has produced warnings that can delay the administration of rubella vaccination postpartum, leaving women susceptible to the disease in subsequent pregnancies. We aimed to address whether the co-administration of the measles, mumps, and rubella (MMR) vaccine and Rhogam decreased antibody responses compared to those receiving only MMR vaccination. This retrospective cohort study utilized clinical data from 78 subjects who received the MMR vaccine and Rhogam after delivery and 45 subjects who received the MMR vaccine alone. Maternal demographics, pregnancy complications and rubella status at the start of a subsequent pregnancy were recorded for analysis. Overall, the two cohorts had similar baseline characteristics; however, lower parity was noted in the participants that received both MMR vaccination and Rhogam. Making assessments based on maternal antibody IgG index for rubella during the next pregnancy, we observed that 88% of the Rhogam + MMR vaccine group had positive serology scores, which was not significantly different from the 80% rate in the MMR-vaccine-only cohort (p = 0.2). In conclusion, no differences were observed in rubella immunity status in subsequent pregnancies in those mothers given both the MMR vaccine and Rhogam concurrently. Given these findings, warnings against co-administration of vaccines in combination with Rhogam appear unwarranted.