Cotyledon-Specific Flow Evaluation of Rhesus Macaque Placental Injury Using Ferumoxytol Dynamic Contrast-Enhanced MRI

BACKGROUND

Recently, dynamic contrast-enhanced (DCE) MRI with ferumoxytol as contrast agent has recently been introduced for the noninvasive assessment of placental structure and function throughout. However, it has not been demonstrated under pathological conditions.

PURPOSE

To measure cotyledon-specific rhesus macaque maternal placental blood flow using ferumoxytol DCE MRI in a novel animal model for local placental injury.

STUDY TYPE

Prospective animal model.

SUBJECTS

Placental injections of Tisseel (three with 0.5 mL and two with 1.5 mL), monocyte chemoattractant protein 1 (three with 100 μg), and three with saline as controls were performed in a total of 11 rhesus macaque pregnancies at approximate gestational day (GD 101). DCE MRI scans were performed prior (GD 100) and after (GD 115 and GD 145) the injection (term = GD 165).

FIELD STRENGTH/SEQUENCE

3 T, T1-weighted spoiled gradient echo sequence (product sequence, DISCO).

ASSESSMENT

Source images were inspected for motion artefacts from the mother or fetus. Placenta segmentation and DCE processing were performed for the dynamic image series to measure cotyledon specific volume, flow, and normalized flow. Overall placental histopathology was conducted for controls, Tisseel, and MCP-1 animals and regions of tissue infarctions and necrosis were documented. Visual inspections for potential necrotic tissue were conducted for the two Tisseelx3 animals.

STATISTICAL TESTS

Wilcoxon rank sum test, significance level P < 0.05.

RESULTS

No motion artefacts were observed. For the group treated with 1.5 mL of Tisseel, significantly lower cotyledon volume, flow, and normalized flow per cotyledon were observed for the third gestational time point of imaging (day ~145), with mean normalized flow of 0.53 minute-1 . Preliminary histopathological analysis shows areas of tissue necrosis from a selected cotyledon in one Tisseel-treated (single dose) animal and both Tisseelx3 (triple dose) animals.

DATA CONCLUSION

This study demonstrates the feasibility of cotyledon-specific functional analysis at multiple gestational time points and injury detection in a placental rhesus macaque model through ferumoxytol-enhanced DCE MRI.

LEVEL OF EVIDENCE

NA TECHNICAL EFFICACY: Stage 2.

Surgical transversus abdominis plane block with liposomal bupivacaine at cesarean: a pilot randomized trial

BACKGROUND

Postcesarean pain control is challenging. In addition to intrathecal morphine, recent studies have shown that liposomal bupivacaine administered via conventional transversus abdominis plane block reduces postcesarean opioid use. However, whether the administration of liposomal bupivacaine via a surgical approach also reduces opioid use is unknown.

OBJECTIVE

This study aimed to investigate whether the administration of liposomal bupivacaine via surgical transversus abdominis plane block (TAP block) reduces the cumulative dose of opioids administered in the first 48 hours after cesarean delivery among participants who also receive intrathecal morphine.

STUDY DESIGN

This was a pilot single-blind randomized controlled trial of 60 parturients undergoing cesarean delivery at a community tertiary referral hospital staffed by academic physicians. Immediately before fascial closure during cesarean delivery, a total of 80 mL of dilute bupivacaine plus liposomal bupivacaine or dilute bupivacaine alone was administered via surgical transversus abdominis plane block (40 mL on each side). The primary outcome was a median cumulative opioid dose received within the first 48 hours after cesarean delivery measured in morphine milligram equivalents. In addition, opioid use at other time points, pain scores, and participant satisfaction were assessed. A sample size of 60 was determined to be adequate to inform a potential future adequately powered randomized trial. The primary outcome of morphine milligram equivalents and pain scores were compared using a Wilcoxon rank-sum test.

RESULTS

Between October 11, 2021, and August 29, 2022, 60 participants were randomized and analyzed: 31 were allocated to liposomal bupivacaine plus regular bupivacaine (intervention group), and 29 were allocated to regular bupivacaine alone (control group). Participants allocated to the intervention group used a median cumulative dose of 2 morphine milligram equivalents of opioids (interquartile range, 0-24) in the first 48 hours compared with 8 morphine milligram equivalents (interquartile range, 0-40) among participants allocated to the control group (P=.236). The percentage of participants who used ≤15 morphine milligram equivalents of opioids was 61% in the intervention arm and 41% in the control arm (P=.123), and the percentage who used zero opioids was 45% in the intervention arm and 34% in the control arm (P=.399). The total number of opioid pills prescribed at discharge was fewer in the intervention arm than in the control arm (P=.029). Patient satisfaction with the intervention group and control group was similar.

CONCLUSION

Our pilot study suggests that liposomal bupivacaine administered via surgical transversus abdominis plane block is worth critical evaluation as an adjunctive analgesic modality in an adequately powered randomized trial.

Maternal, placental and fetal response to a non-viral, polymeric nanoparticle gene therapy in nonhuman primates

Background

Currently, there are no placenta-targeted treatments to alter the in utero environment. Water-soluble polymers have a distinguished record of clinical relevance outside of pregnancy. We have demonstrated the effective delivery of polymer-based nanoparticles containing a non-viral human insulin-like 1 growth factor ( IGF1 ) transgene to correct placental insufficiency in small animal models of fetal growth restriction (FGR). Our goal was to extend these studies to the pregnant nonhuman primate (NHP) and assess maternal, placental and fetal responses to nanoparticle-mediated IGF1 treatment.

Methods

Pregnant macaques underwent ultrasound-guided intraplacental injections of nanoparticles ( GFP- or IGF1- expressing plasmid under the control of the trophoblast-specific PLAC1 promoter complexed with a HPMA-DMEAMA co-polymer) at approximately gestational day 100 (term = 165 days). Fetectomy was performed 24 h ( GFP ; n =1), 48 h ( IGF1 ; n = 3) or 10 days ( IGF1 ; n = 3) after nanoparticle delivery. Routine pathological assessment was performed on biopsied maternal tissues, and placental and fetal tissues. Maternal blood was analyzed for complete blood count (CBC), immunomodulatory proteins and growth factors, progesterone (P4) and estradiol (E2). Placental ERK/AKT/mTOR signaling was assessed using western blot and qPCR.

Findings

Fluorescent microscopy and in situ hybridization confirmed placental uptake and transgene expression in villous syncytiotrophoblast. No off-target expression was observed in maternal and fetal tissues. Histopathological assessment of the placenta recorded observations not necessarily related to the IGF1 nanoparticle treatment. In maternal blood, CBCs, P4 and E2 remained within the normal range for pregnant macaques across the treatment period. Changes to placental ERK and AKT signaling at 48 h and 10 d after IGF1 nanoparticle treatment indicated an upregulation in placental homeostatic mechanisms to prevent over activity in the normal pregnancy environment.

Interpretation

Maternal toxicity profile analysis and lack of adverse reaction to nanoparticle-mediated IGF1 treatment, combined with changes in placental signaling to maintain homeostasis indicates no deleterious impact of treatment.

Funding

National Institutes of Health, and Wisconsin National Primate Research Center.

Continuous positive airway pressure treatment of obstructive sleep apnea and hypertensive complications in high-risk pregnancy

PURPOSE

To evaluate whether or not continuous positive airway pressure (CPAP) treatment in pregnancies complicated by obstructive sleep apnea (OSA) is associated with a decrease in hypertensive disorders of pregnancy.

METHODS

This was a retrospective cohort study of perinatal outcomes in women who underwent objective OSA testing and treatment as part of routine clinical care during pregnancy. Where diagnostic criteria for OSA were reached (respiratory event index (REI) ≥ 5 events per hour), patients were offered CPAP therapy. Obstetrical outcomes were compared between the control group (no OSA), the group with untreated OSA (OSA diagnosed, not CPAP compliant), and the group with treated OSA (OSA diagnosed and CPAP compliant), with CPAP compliance defined as CPAP use ≥ 4 h, 70% of the time or greater. A composite hypertension outcome combined diagnoses of gestational hypertension (gHTN) and preeclampsia (PreE) of any severity.

RESULTS

The study comprised outcomes from 177 completed pregnancies. Our cohort was characterized by obesity, with average body mass indices > 35 kg/m2, and average maternal age > 30 years old. CPAP was initiated at an average gestational age of 23 weeks (12.1-35.3 weeks), and average CPAP use was 5.9 h (4-8.5 h). The composite hypertension outcome occurred in 43% of those without OSA (N = 77), 64% of those with untreated OSA (N = 77), and 57% of those with treated OSA, compliant with CPAP (N = 23) (p = 0.034).

CONCLUSION

Real-world data in this small study suggest that CPAP therapy may modulate the increased risk of hypertensive complications in pregnancies complicated by OSA.

SERUM GLP-2 is Increased in Association with Excess Gestational Weight Gain

OBJECTIVE

Obesity in pregnancy bears unique maternal and fetal risks. Obesity has also been associated with chronic inflammation, including elevated serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Higher serum lipopolysaccharide (LPS) levels have been implicated in driving this inflammation, a phenomenon called metabolic endotoxemia (ME). GLP-2, a proglucagon-derived peptide, is believed to be integral in maintaining the integrity of the intestine in the face of LPS-mediated endotoxemia. We hypothesized that obesity and/or excess weight gain in pregnancy would be associated with an increase in maternal and neonatal markers of ME, as well as GLP-2.

STUDY DESIGN

Paired maternal and neonatal (cord blood) serum samples (n = 159) were obtained from our pregnancy biobank repository. Serum levels of LPS, endotoxin core antibody-immunoglobulin M (EndoCAb-IgM), and GLP-2 were measured by ELISA. IL-6 and TNF-α were measured using a Milliplex assay. Results were stratified by maternal body mass index (BMI), maternal diabetes, and gestational weight gain (GWG).

RESULTS

Maternal IL-6 is significantly decreased in the obese, diabetic cohort compared with the nonobese, nondiabetic cohorts (95.28 vs. 99.48 pg/mL, p = 0.047), whereas GLP-2 is significantly increased (1.92 vs. 2.89 ng/mL, p = 0.026). Neonatal TNF-α is significantly decreased in the obese cohort compared with the nonobese cohort (12.43 vs. 13.93 pg/mL, p = 0.044). Maternal GLP-2 is significantly increased in women with excess GWG compared with those with normal GWG (2.27 vs. 1.48 ng/mL, p = 0.014). We further found that neonatal IL-6 and TNF-α are negatively correlated with maternal BMI (-0.186, p = 0.036 and -0.179, p = 0.044, respectively) and that maternal and neonatal IL-6 showed a positive correlation (0.348, p < 0.001).

CONCLUSION

Although we observed altered levels of markers of inflammation (IL-6 and TNF-α) with maternal obesity and diabetes, no changes in LPS or endoCAb-IgM were observed. We hypothesize that the increased GLP-2 levels in maternal serum in association with excess GWG may protect against ME in pregnancy.

KEY POINTS

· Maternal serum levels of GLP-2, a proglucagon-derived peptide, are increased in obese, diabetic gravidae.. · Maternal serum GLP-2 levels are also increased in association with excess gestational weight gain compared with normal gestational weight gain.. · GLP-2 may be increased in association with obesity and weight gain to protect against metabolic endotoxemia in pregnancy..

Frequent first-trimester pregnancy loss in rhesus macaques infected with African-lineage Zika virus

In the 2016 Zika virus (ZIKV) pandemic, a previously unrecognized risk of birth defects surfaced in babies whose mothers were infected with Asian-lineage ZIKV during pregnancy. Less is known about the impacts of gestational African-lineage ZIKV infections. Given high human immunodeficiency virus (HIV) burdens in regions where African-lineage ZIKV circulates, we evaluated whether pregnant rhesus macaques infected with simian immunodeficiency virus (SIV) have a higher risk of African-lineage ZIKV-associated birth defects. Remarkably, in both SIV+ and SIV- animals, ZIKV infection early in the first trimester caused a high incidence (78%) of spontaneous pregnancy loss within 20 days. These findings suggest a significant risk for early pregnancy loss associated with African-lineage ZIKV infection and provide the first consistent ZIKV-associated phenotype in macaques for testing medical countermeasures.

Does Daily Self-Weighing Contribute to Postpartum Weight Loss? A Secondary Analysis of Daily Postpartum Weights among Women with Hypertensive Disorders of Pregnancy

OBJECTIVE

This study was aimed to examine the impact of daily self-weighing via remote monitoring on postpartum weight loss.

STUDY DESIGN

This was a secondary analysis of a nonrandomized controlled trial comprised of postpartum women with diagnosed hypertensive-related disorders in pregnancy who received a tablet device linked to Bluetooth-enabled equipment including a scale and blood pressure cuff. In addition to blood pressure monitoring, participants were instructed to perform daily self-weighing. The primary outcome of this study was to determine whether postpartum women who performed daily self-weighing lost more weight than those who did not, with a 42-day endpoint based on a 6-week postpartum visit weight.

RESULTS

Overall, 214 women participated in this program and 214 received usual care. Median weight loss for women participating in the remote blood pressure monitoring system was 23.0 (interquartile range [IQR]: 17-30) pounds versus 23.0 (IQR: 17-29) pounds among controls. Weight loss did not vary by prepregnancy obesity (median: 20 pounds [IQR: 17-28 pounds] for nonobese and 23 [IQR: 17-30] pounds for women with obesity, p = 0.16). Women who weighed themselves more than half of follow-up days lost a median of 24 pounds (IQR: 17-30 pounds) compared with 20.5 pounds (IQR: 14-29 pounds), p = 0.06. Women who weighed themselves more than half of follow-up days lost a mean of 11.4% (standard deviation [SD] = 0.41%) of body weight compared with 9.1% (SD = 0.74%; p = 0.01). The amount of weight loss in the telehealth group was correlated with the number of daily weights performed (Pearson's correlation coefficient 0.164, p = 0.025). Postpartum weight loss for daily self-weighing participants was most notable in the first 2 weeks with ongoing weight loss up to the 42-day (6-week) endpoint of this secondary analysis.

CONCLUSION

Daily self-weighing alone may be insufficient to promote postpartum weight loss. However, there was a slight trend toward more weight loss with more frequent weighing.

KEY POINTS

· Daily self-weighing is insufficient for postpartum weight loss.. · Women who weighed themselves more lost slightly more weight.. · Weight loss was the most notable in the first 2 weeks.. · Its use as one part of a program may be worth studying..

Clinical application of a previously validated pregnancy-specific screening tool for sleep apnea in a cohort with a high prevalence of obesity

Objective

The purpose of this project was to determine the positive predictive value of existing obstructive sleep apnea (OSA) screening tools in clinical use, in a real-world clinical population of gravidae, and to explore the development of a new questionnaire for screening for OSA during pregnancy.

Methods

Pregnant people were administered sleep screening questionnaires as part of routine clinical care. These included Facco's four variable OSA screening tool, the STOP-BANG, and the Epworth Sleepiness Scale. Those who screened positive were referred for diagnostic sleep testing, typically with a type III home monitoring device. Here we analyzed the screening responses used by those who completed diagnostic testing to determine the positive predictive value of the existing tools.

Results

159 pregnant people completed diagnostic OSA testing and were included in this analysis. The positive predictive value of Facco's four variable sleep screening tool was 74.3%, STOP-BANG was 75.3%, and the Epworth Sleepiness Scale was 69.8%. Our sample size was insufficient to create a new screening tool.

Conclusions

Here we calculated the positive predictive value of Facco's 4 variable screening tool for screening for OSA in pregnancy in a real-world pregnant population. While we were not able to generate a new screening tool for screening for OSA during pregnancy, both STOP-BANG and Facco's four variable tool had positive predictive values over 70% in our population which was characterized by high BMI and advanced maternal age. Increased clinical use of the pregnancy-specific tool may be warranted.

Racial disparities in post-operative pain experience and treatment following cesarean birth

OBJECTIVE

To evaluate racial/ethnic differences in post-operative pain experience and opioid medication use (morphine milligram equivalent) in the first 24 h following cesarean birth.

METHODS

This study was a single-center retrospective cohort of birthing persons who underwent cesarean deliveries between 1/1/16 and 12/31/17. A total of 2,228 cesarean deliveries were analyzed. The primary outcome was average pain, which was the mean of all documented self-reported pain scores (0-10 scale) during the first 24 h post-delivery. The secondary outcome included oral morphine equivalents used in the first 24 h post-delivery. Linear regression was performed to examine whether the race/ethnicity of the birthing parent was associated with mean pain scores and oral morphine equivalents, controlling for confounding variables.

RESULTS

In multivariate analyses non-Hispanic Black birthing persons reported higher mean pain scores (Coefficient: 0.61, 95% confidence interval [0.39-0.82], p < .001]) than non-Hispanic White birthing persons, but received similar quantities of morphine milligram equivalent (Coefficient: -0.98 mg, 95% confidence interval [-5.93-3.97], p = .698]). Non-Hispanic Asian birthing persons reported similar reported mean pain scores to those of non-Hispanic White birthing persons (Coefficient: 0.02 mg, 95% confidence interval [-0.17-0.22], p = .834]), but received less morphine milligram equivalent (Coefficient: -5.47 mg, 95% confidence interval [-10.05 to -0.90], p = .019). When controlling for reported mean pain scores, both non-Hispanic Black (Coefficient: -6.36 mg, 95% confidence interval [-10.97 to -1.75], p = .007) and non-Hispanic Asian birthing persons (Coefficient: -5.66 mg, 95% confidence interval [-9.89 to -1.43], p = .009) received significantly less morphine milligram equivalents.

CONCLUSION

Despite reporting higher mean pain scores, non-Hispanic Black birthing persons did not receive higher quantities of morphine milligram equivalent. Non-Hispanic Asian birthing persons received lower quantities of morphine milligram equivalent despite reporting similar pain scores to non-Hispanic White birthing persons. These differences suggest disparities in post-operative pain management for birthing persons of color in our study population.

Fetal loss in pregnant rhesus macaques infected with high-dose African-lineage Zika virus

Countermeasures against Zika virus (ZIKV), including vaccines, are frequently tested in nonhuman primates (NHP). Macaque models are important for understanding how ZIKV infections impact human pregnancy due to similarities in placental development. The lack of consistent adverse pregnancy outcomes in ZIKV-affected pregnancies poses a challenge in macaque studies where group sizes are often small (4-8 animals). Studies in small animal models suggest that African-lineage Zika viruses can cause more frequent and severe fetal outcomes. No adverse outcomes were observed in macaques exposed to 1x104 PFU (low dose) of African-lineage ZIKV at gestational day (GD) 45. Here, we exposed eight pregnant rhesus macaques to 1x108 PFU (high dose) of African-lineage ZIKV at GD 45 to test the hypothesis that adverse pregnancy outcomes are dose-dependent. Three of eight pregnancies ended prematurely with fetal death. ZIKV was detected in both fetal and placental tissues from all cases of early fetal loss. Further refinements of this exposure system (e.g., varying the dose and timing of infection) could lead to an even more consistent, unambiguous fetal loss phenotype for assessing ZIKV countermeasures in pregnancy. These data demonstrate that high-dose exposure to African-lineage ZIKV causes pregnancy loss in macaques and also suggest that ZIKV-induced first trimester pregnancy loss could be strain-specific.

Human immune globulin treatment controls Zika viremia in pregnant rhesus macaques

There are currently no approved drugs to treat Zika virus (ZIKV) infection during pregnancy. Hyperimmune globulin products such as VARIZIG and WinRho are FDA-approved to treat conditions during pregnancy such as Varicella Zoster virus infection and Rh-incompatibility. We administered ZIKV-specific human immune globulin as a treatment in pregnant rhesus macaques one day after subcutaneous ZIKV infection. All animals controlled ZIKV viremia following the treatment and generated robust levels of anti-Zika virus antibodies in their blood. No adverse fetal or infant outcomes were identified in the treated animals, yet the placebo control treated animals also did not have signs related to congenital Zika syndrome (CZS). Human immune globulin may be a viable prophylaxis and treatment option for ZIKV infection during pregnancy, however, more studies are required to fully assess the impact of this treatment to prevent CZS.

Gestational Intermittent Hypoxia Induces Sex-Specific Impairment in Endothelial Mechanisms and Sex Steroid Hormone Levels in Male Rat Offspring

Obstructive sleep apnea (OSA) is highly prevalent during gestation and is linked with adverse fetal outcomes. We examined whether gestational intermittent hypoxia (GIH), the main feature of OSA, leads to sex-specific alterations in cardiovascular function and vascular mechanisms in the offspring. Pregnant rats exposed to intermittent hypoxia or ambient air from gestation days 10 to 21 and their offspring were used for the study. GIH exposure did not affect water and food intake in dams. Compared to controls, the male and female offspring born to GIH dams were smaller in weight by 14% and 12%, respectively, and exhibited catch-up growth. Cardiac function was not affected in either GIH males or females. At 12 weeks of age, blood pressure was increased in GIH males, but not GIH females, compared to their control counterparts. While mesenteric arterial contractile responses to phenylephrine and endothelin were unaffected in GIH males and females, relaxation response to acetylcholine was reduced in GIH males but not GIH females. Relaxation to sodium nitroprusside was unaffected in both GIH males and females. Total eNOS expression was not affected, but phospho(Ser1177)-eNOS levels were decreased in GIH males. eNOS expression and its phosphorylation status were unaffected in GIH females. Serum testosterone and estradiol levels were higher in GIH males but were unaltered in GIH females. Together, these findings suggest that GIH leads to a sex-specific increase in blood pressure in adult male offspring with blunted endothelium-mediated relaxation, decreased eNOS activity, and elevated sex steroid hormone levels.

Weight gain in pregnancy: can metformin steady the scales?

OBJECTIVE

Metformin has been associated with modest weight reduction in the non-pregnant population. Our hypothesis is that metformin exposure will lead to a higher incidence of appropriate weight gain during pregnancy.

STUDY DESIGN

This was a retrospective cohort study in a single center between 2009 and 2019. We included all pregnant women with type 2 diabetes or prediabetes. We compared women exposed to metformin in any trimester. The primary outcome was appropriate weight gain defined by the Institute of Medicine guidelines. Secondary outcomes included excessive weight gain, weight loss, suspected fetal growth restriction (FGR), and mean birth weight. Adjusted odds ratios or group differences were calculated using logistic or linear regression, controlling for confounders.

RESULTS

Of 41,472 deliveries during the study period, 511 pregnancies met inclusion criteria. 284 pregnancies had no metformin exposure; 227 did have metformin exposure, of which 169 (72.2%) were initiated on metformin in the first trimester. Women exposed to metformin in any trimester were statistically not more likely to have appropriate weight gain (aOR 1.53 (95% CI 1.00-2.34, p = .048), but did have less excess weight gain (aOR 0.45, 95% CI 0.30-0.66, p < .001), and more maternal weight loss (aOR 2.17, 95% CI 1.18-3.98, p = .012) than the unexposed group. Women exposed to metformin in the first trimester of pregnancy were less likely to have excess weight gain (aOR 0.39, 95% CI 0.25-0.61, p < .001) and more likely to have maternal weight loss (aOR 2.56, 95% CI 1.30-5.07, p = .007) than the unexposed cohort. There was no difference in FGR (5.3% vs 2.5% p = .094) or mean birth weight (3235.6 vs 3352.4 gm p = .122) in the metformin exposed group vs non-exposed groups, respectively.

CONCLUSIONS

Metformin exposure in pregnancy was associated with less excess weight gain and a higher rate of weight loss. There was no difference in FGR or mean birth weight in metformin exposed neonates. This suggests that metformin may help avoid excess weight gain and its associated comorbidities.

Postoperative Respiratory Compromise following Cesarean Birth: The Impact of Obesity and Systemic Opioids

Objective  The aim of this study was to measure the effect of obesity and systemic opioids on respiratory events within the first 24 hours following cesarean. Methods  Opioid-naive women undergoing cesarean between January 2016 and December 2017 were included in this retrospective cohort study. The primary outcome was the proportion of women experiencing at least one composite respiratory outcome (oxygen saturation less than 95% lasting 30+ seconds or need for respiratory support) within 24 hours of cesarean. The impact of obesity and total systemic opioid dose in 24 hours (measured in morphine milligram equivalents [MMEs]) on the composite respiratory compromise outcome were evaluated. Results  Of 2,230 cesarean births, 790 women had at least one composite respiratory event. Predictors of the composite respiratory outcome included body mass index (BMI) as a continuous variable (odds ratio = 1.063 for every one unit increase in BMI [95% confidence interval (CI): 1.021-1.108], p  = 0.003), and MME (odds ratio = 1.005 [95% CI: 1.002-1.008], p  = 0.003), adjusting for magnesium sulfate use. The interaction between obesity and opioid dose demonstrated an odds ratio of 1.000 (95% CI: 0.999-1.000, p  = 0.030). Conclusion  The proportion of women experiencing respiratory events following cesarean birth increases with the degree of obesity and opioid dose. Key Points Respiratory events increase with obesity.Respiratory events increase with systemic opioid use.Odds ratio of respiratory events is 1.063/unit BMI increase.

Anxiety, Depression, and Pain in the Perinatal Period: A Review for Obstetric Care Providers

Importance

Maternal depression and anxiety may not only increase vulnerability for the development of postpartum depression and anxiety but may increase the perception of obstetric pain.

Objective

This review focuses on the relationship among depression, anxiety, and pain during pregnancy and postpartum. We will first review common clinical screening tools for depression, anxiety, and pain. Then, the existing evidence describing the relationship of depression, anxiety, and pain will be covered.

Evidence Acquisition

Queries for publications in PubMed, Google Scholar, and the CINAHL (Cumulative Index to Nursing and Allied Health Literature) were completed. Both searches were limited to publications within the last 20 years. Literatures on subtopics obtained from the references of publications identified in the initial search were not limited by publication year.

Results

A total of 19 total publications were identified regarding postpartum depression and pain; 17 were identified in the initial search, and 2 related to postpartum depression, anxiety, and pain were found by reviewing references. Eleven studies were identified regarding postpartum anxiety and pain; 4 were found in the original search, and 7 were identified by reviewing the references.

Conclusions and Relevance

The relationship between postpartum depression and pain is well characterized in the literature. However, the relationship between postpartum anxiety and pain is less well defined, and further research is needed. The interaction between maternal mental health and pain emphasizes the importance of screening for these conditions and also counseling and educating patients about expectations regarding intrapartum and postpartum pain.

Metformin Exposure and Risk of Hypertensive Disorders of Pregnancy in Patients with Type 2 Diabetes

OBJECTIVE

Metformin has been found to have a role in promoting vascular remodeling and angiogenesis which may reduce the risk of developing preeclampsia. Prior studies have shown a decrease in the incidence of hypertensive disorders of pregnancy in patients with type 2 and gestational diabetes taking metformin. We hypothesize metformin exposure decreases the risk of developing hypertension in patients with type 2 diabetes.

STUDY DESIGN

Retrospective cohort study from 2009 to 2019 of singleton pregnancies was complicated by type 2 diabetes. We compared patients who received metformin throughout pregnancy to those with no metformin exposure. The primary outcome was a hypertension composite defined as gestational hypertension, preeclampsia with or without severe features, HELLP syndrome, or eclampsia. Individual hypertensive outcomes and neonatal outcomes were secondarily evaluated. Logistic regression was used to adjust for confounding variables.

RESULTS

A total of 254 pregnancies were included. Women exposed to metformin were significantly less likely to develop hypertension composite compared with nonexposed women (22.7 vs. 33.1%, aOR 0.53, 95% CI 0.29-0.96). The incidence of preeclampsia with severe features was also significantly lower in those who received metformin compared with those who did not (12.1 vs. 20.7%, aOR 0.38, 95% CI 0.18-0.81). There were no differences in preterm birth prior to 34 or 37 weeks, fetal growth restriction, or birth weight between the study groups. A subgroup analysis of women without chronic hypertension also had a significantly lower risk of developing preeclampsia with severe features (7.6 vs. 17.8%, aOR 0.35, 95% CI 0.13-0.94).

CONCLUSION

Metformin exposure was associated with a decreased risk of composite hypertensive disorders of pregnancy in patients with pregestational type 2 diabetes. These data suggest that there may be benefit to metformin administration beyond glycemic control in this patient population.

KEY POINTS

· Metformin use showed a decreased risk of a hypertension composite.. · Results were consistent in patients without chronic hypertension.. · Metformin may show benefit beyond glycemic control in women with type 2 diabetes..

A Matter of Time: Does Gestational Age Affect the Duration of the Fetal Anatomic Survey?

OBJECTIVE

To assess the average duration of detailed fetal anatomic surveys in pregnancy in relation to gestational age (GA) and the maternal body mass index (BMI) to determine optimal timing of the examination.

METHODS

This was a retrospective cohort study of gravidae presenting for detailed fetal anatomic examinations between January 1, 2010, and June 30, 2017. After excluding examinations expected to have longer duration (ie, multifetal, major fetal anomalies), there were a total of 6522 examinations performed between GAs of 18 weeks 0 days and 22 weeks 0 days. Women were grouped by BMI, and results were analyzed by logistic regression.

RESULTS

Gravidae of normal weight (BMI, 18.5-24.9 kg/m² ) had a decrease of 47.47 seconds of the examination time with each increasing week of gestation (P = .036). Overweight (BMI, 25-29.9 kg/m² ) gravidae similarly had a decrease of 66.31 seconds of the examination time with each additional week of gestation (P = .017). Underweight (BMI, 8.5 kg/m² ) and obese (BMI, ≥30 kg/m² ) gravidae did not have differences in the examination time with increasing GA. Increases in suboptimal examinations were noted with an increasing BMI (P < .001). There was a decreased frequency of suboptimal examinations in obese gravidae with a BMI of 40 kg/m² or higher with increasing GA (P = .037).

CONCLUSIONS

The duration of detailed fetal anatomic examinations decreased with increasing GA in normal-weight and overweight gravidae but not in obese gravidae. Performing the anatomy scan earlier in class I and II obese gravidae (BMI, 30-40 kg/m² ) may enable improved pregnancy management options without increasing the examination duration or likelihood of a suboptimal evaluation.

A standardized post-cesarean analgesia regimen reduces postpartum opioid use

BACKGROUND

Optimal post-cesarean pain control is important. With the rising opioid epidemic it is imperative to maximize non-opioid based primary approaches to post-cesarean pain control. In 2018, we implemented a standardized post-cesarean analgesia regimen.

OBJECTIVE

To determine if implementation of a standardized postoperative analgesic regimen decreases opioid use following cesarean birth.

STUDY DESIGN

A standardized postoperative analgesia protocol was implemented in June 2018, which included scheduled oral acetaminophen (975 mg every 6 h) and nonsteroidal anti-inflammatory drugs (NSAIDs) (ketorolac 15 mg IV every 6 h for 5 doses followed by ibuprofen 600 mg oral every 6 h) with opioids available for breakthrough pain. There was no prior standardized protocol. A before-and-after study design was used to compare oral morphine milligram equivalents (MME) for nine months prior to and nine months after this protocol was implemented, excluding the two month period of protocol rollout. Women with opioid use disorder or postoperative intubation were excluded. The primary outcome was the cumulative MME used in the first 72 h postoperatively. Total dose at 12, 24, and 48 h were also compared.

RESULTS

Of 2340 women who underwent cesarean birth during the study period (1 July 2017 - 30 April 2019), 2001 women met inclusion criteria (914 before 10 April 2018 (pre-protocol) and 1087 after 17 June 2018 (post-protocol)). Baseline characteristics of the two groups were similar, including gestational age at delivery, maternal body mass index (BMI), planned versus unplanned cesarean birth, and type of intraoperative anesthesia used. The cumulative opioid dose in the first 72 h postoperatively was 216.3 ± 84.3 MME prior to implementation compared to 171.5 ± 91.5 MME following implementation (p < .001). The average cumulative MME use was higher in the pre-protocol period compared to post-protocol at all time periods: 12 h (57.3 ± 23.8 vs 48.6 ± 26.2 MME, p < .001), 24 h (98.1 ± 34.1 vs 82.1 ± 38.8 MME, p < .001), and 48 h (165.8 ± 58.3 vs 134.9 ± 66.2 MME, p < .001). The average pain scores were lower in the pre-protocol group (3 vs 3.3, p < .001).

CONCLUSION

Scheduled administration of acetaminophen and NSAIDs following cesarean birth significantly decreased the cumulative dose of opioids used in the first 72 h postoperatively.

Maternal Metabolic Biomarkers are Associated with Obesity and Excess Gestational Weight Gain

OBJECTIVE

The purpose of this study was to evaluate the independent contribution of maternal obesity and gestational weight gain (GWG) in excess of the Institute of Medicine's guidelines on levels of maternal serum inflammatory and metabolic measures.

STUDY DESIGN

Banked maternal serum samples from 120 subjects with documented prepregnancy or first trimester body mass index (BMI) were utilized for analyte analyses. Validated, BMI-specific formulas were utilized to categorize GWG as either insufficient, at goal or excess based on the Institute of Medicine guidelines with gestational age adjustments. Serum was analyzed for known inflammatory or metabolic pathway intermediates using the Luminex xMap system with the MILLIPLEX Human Metabolic Hormone Magnetic Bead Panel. Measured analytes included interleukin-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α and metabolic markers amylin, c-peptide, ghrelin, gastric inhibitory polypeptide, glucagon-like peptide-1, glucagon, insulin, leptin, pancreatic polypeptide, and peptide YY. Kruskal-Wallis ANOVA and Pearson's correlation coefficients were calculated for each marker.

RESULTS

C-peptide, insulin, and leptin all varied significantly with both obesity and GWG while glucagon-like peptide-1 varied by BMI but not GWG. These analytes covaried with other metabolic analytes, but not with inflammatory analytes.

CONCLUSION

Maternal metabolic biomarkers at delivery vary significantly with both obesity and GWG. Taken together, these findings suggest that GWG (with and without comorbid obesity) is an important mediator of measurable metabolites in pregnancy but is not necessarily accompanied by inflammatory measures in serum. These findings are consistent with GWG being an independent risk factor for metabolic disturbances during pregnancy.

Previous exposure to dengue virus is associated with increased Zika virus burden at the maternal-fetal interface in rhesus macaques

Concerns have arisen that pre-existing immunity to dengue virus (DENV) could enhance Zika virus (ZIKV) disease, due to the homology between ZIKV and DENV and the observation of antibody-dependent enhancement (ADE) among DENV serotypes. To date, no study has examined the impact of pre-existing DENV immunity on ZIKV pathogenesis during pregnancy in a translational non-human primate model. Here we show that macaques with a prior DENV-2 exposure had a higher burden of ZIKV vRNA in maternal-fetal interface tissues as compared to DENV-naive macaques. However, pre-existing DENV immunity had no detectable impact on ZIKV replication kinetics in maternal plasma, and all pregnancies progressed to term without adverse outcomes or gross fetal abnormalities detectable at delivery. Understanding the risks of ADE to pregnant women worldwide is critical as vaccines against DENV and ZIKV are developed and licensed and as DENV and ZIKV continue to circulate.

Barriers to Self-Disclosing Level of Maternal Care: What Are Wisconsin Hospitals Worried About?

OBJECTIVE

The American College of Obstetrics and Gynecology (ACOG) has recommended every hospital disclose their level of maternal care (LOMC) to categorize the capabilities of their birthing center and regionalize perinatal care. Of the 98 birthing centers in Wisconsin, 44% have self-disclosed their LOMC. In many states, disclosing LOMC is mandated but, despite evidence and professional association recommendations, Wisconsin relies on voluntary self-reporting. We surveyed all birthing centers in Wisconsin to better understand the barriers to disclosing their LOMC.

STUDY DESIGN

An anonymous survey was sent to all 98 birthing centers in Wisconsin. Survey recipients were hospital administrators, nursing supervisors, or physician directors of obstetric units. The survey sought information on perceived barriers to completing self-assessments and disclosing their hospital's LOMC. Quantitative descriptive statistics were used for data analysis.

RESULTS

Of 98 birth centers in Wisconsin, 40 (40.8%) responded. Fifteen of the 40 responses were from birthing centers that have not yet disclosed their LOMC. Of these, 93% were unsure how to disclose, 73% found the paperwork confusing, and 80% did not have the time or staff to complete the paperwork. Respondents did not report lack of departmental support, concerns about losing business or reputation, or future physician recruitment as barriers. Of all respondents, 77.5% were aware of ACOG's LOMC recommendations, but only 35% thought disclosing their LOMC would be beneficial to maternal care.

CONCLUSIONS

Birthing centers in Wisconsin need further guidance on how to complete a self-assessment of their LOMC. In order to increase self-disclosure of LOMC, statewide perinatal organizations will need to continue to emphasize the benefits of releasing this information. Organizations should also provide additional support to level 1 and 2 birthing centers and improve maternal and neonatal care overall.

Obstructive Sleep Apnea in Pregnancy: Early Lessons From Our Sleep Pregnancy Clinic

PROBLEM CONSIDERED

Obstructive sleep apnea (OSA) is underdiagnosed during pregnancy, but there is strong theoretical and some empiric evidence that treatment may improve obstetric outcomes. Barriers to screening, testing, and treatment are common during pregnancy. The goal of this described intervention was to reduce these barriers and improve detection of OSA in pregnancy.

METHODS

Representatives from sleep medicine and perinatology established a cross-disciplinary, collaborative Sleep Pregnancy Clinic offering a streamlined referral process for multimodal screening, testing, and treatment of OSA during pregnancy. This is a retrospective analysis of data from the clinic's first 19 months.

RESULTS

Between June 2017 and December 2018, 134 pregnant women were referred for OSA testing. Sixty-three (47.0%) completed objective sleep testing, and 38 (60.3%) of the women who completed testing met diagnostic criteria for OSA. This intervention resulted in a statistically significant increase in the number of diagnostic sleep apnea tests performed (average 22.4 tests per year pre-intervention, 77 per year post-intervention [P  = 0.0012]).

DISCUSSION AND CONCLUSIONS

Despite a streamlined referral pipeline, completion rates of OSA testing in pregnant women remained below 50%. However, the overall number of women referred and who completed testing increased significantly during this time period. Of those who completed testing, the majority were diagnosed with OSA. Since starting this clinic, we have created resources to familiarize patients with the equipment and worked to reduce other barriers. Assessment of these interventions and the impact of treatment on obstetric outcomes is ongoing, as is assessment of reasons women do not complete diagnostic testing.

Prenatal care experiences among pregnant women with obesity in Wisconsin, United States: a qualitative quality improvement assessment

BACKGROUND

Stigma and bias experienced during prenatal care can affect quality of care and, ultimately, the health of pregnant women with obesity and their infants. We sought to 1) better understand the bias and stigma that women with BMIs ≥40 kg/m2 experience while receiving prenatal care, 2) gauge women's interest in group prenatal education for women with obesity, and 3) gather feedback about their preferred weight-related terminology.

METHODS

We conducted and thematically content-analyzed 30 semi-structured interviews of women with BMIs ≥40 kg/m2 who received prenatal care at a university-affiliated teaching hospital in the Midwest region of the United States.

RESULTS

All women recalled positive experiences during their perinatal care during which they felt listened to and respected by providers. However, many also described a fear of weight-related bias or recalled weight-based discrimination. Women reacted favorably to a proposed group prenatal care option for pregnant women with obesity that focused on nutrition, physical activity, and weight management. Women rated "weight" and "BMI" as the most desirable terms for describing weight, while "large size" and "obesity" were rated least desirable.

CONCLUSIONS

Many pregnant women with BMIs ≥40 kg/m2 experience bias in the prenatal care setting. Potential steps to mitigate bias towards weight include improving provider awareness of the experiences and perspectives of this population, expanding prenatal care options targeted towards women with high BMIs, including group care, and using patient-preferred weight-related terminology. Through the remainder of this manuscript, wherever possible, the term "high BMI" will be used in place of the term "obesity" to describe women with BMI ≥ 30 kg/m2 in order to respect the preferred terminology of the women we interviewed.

Population-Based Estimation of the Preterm Birth Rate in Lilongwe, Malawi: Making Every Birth Count

Objective  The objective of this study was to perform a population-based estimation of the preterm birth (PTB) rate in regions surrounding Lilongwe, Malawi. Study Design  We partnered with obstetrician specialists, community health workers, local midwives, and clinicians in a 50 km region surrounding Lilongwe, Malawi, to perform a population-based estimation of the PTB rate during the study period from December 1, 2012 to May 19, 2015. Results  Of the 14,792 births captured, 19.3% of births were preterm, including preterm early neonatal deaths. Additional PTB risk factors were similarly prevalent including domestic violence, HIV, malaria, anemia, and malnutrition. Conclusion  When performing a population-based estimation of the rate of PTB, including women without antenatal care and women delivering at home, the 19.3% rate of PTB is among the highest recorded globally. This is accompanied by a high rate of risk factors and comorbid conditions.

Travel During Pregnancy: A Study of Postpartum Women in Madison, Wisconsin

PROBLEM CONSIDERED

While travel during pregnancy is increasingly common, both the act of traveling and the destination itself may pose risks to pregnant women. Thus, it is relevant to ask pregnant women about travel for individual care and to assess how often pregnant women travel. Based upon our prior study, we hypothesized that domestic travel would be common, with approximately 30% of pregnant women traveling, and that international travel also would be common, with approximately 5% of the population traveling. We also hypothesized that maternal characteristics, such as socioeconomic status, country of birth, and parity, would affect domestic and international travel during pregnancy.

METHODS

In order to study trends in travel by pregnant women, a survey was conducted among postpartum women at Meriter Hospital in Madison, Wisconsin, between October 17, 2016 and March 21, 2017.

RESULTS

Of the 61 postpartum women surveyed, 75.4% had traveled domestically and 11.4% had traveled internationally while pregnant. Those who traveled domestically had a significantly higher level of education (P = 0.025) and higher annual income (P = 0.001) compared to women who did not travel domestically. There were no differences in these characteristics between those who did and did not travel internationally. Women traveling domestically were less likely to discuss their travel plans with their obstetrician when compared to women traveling internationally (67.4% v 85.7%, respectively). Out of 19 canceled trips, both domestic and international, 4 women opted to cancel their trips due to concerns about Zika virus (21.1%).

CONCLUSION

This study allowed for an in-depth look at pregnant travelers and their reasons for traveling and for canceling their trips. When travel plans were discussed, in most instances (94.6%), the obstetrician initiated the conversation. As pregnant women travel both domestically and internationally at increasing rates, it is important to discuss risks associated with travel.

Population-Based Estimation of Dental Caries and Periodontal Disease Rates of Gravid and Recently Postpartum Women in Lilongwe, Malawi

Objectives  The objective of this study was to determine the rate of dental caries and periodontal disease among gravid and recently postpartum women at five delivery centers within and surrounding Lilongwe, Malawi. Study Design  We partnered with obstetric specialists, community health workers, and dentists to perform dental history interviews and dental examinations during the study period from December 2012 to May 2014. Dental examinations were performed according to World Health Organization standards to assess periodontal and oral health status. Results  Among the 387 gravid and recently postpartum women, the rate of dental caries was 69.3% and the rate of composite dental disease (caries and periodontal disease) was 76.7%. The majority (69.5%) of women examined had a decayed-missing-filled (DMF) index greater than or equal to one; the average DMF Index was 2.48. The majority of women had never seen a dentist (62.8%). However, most did perform oral hygiene, two or more times per day (90.2%); most women reported brushing with toothpaste (88.1%). Conclusion  When assessing this population for dental caries and periodontal disease, the rate of dental disease was high. Therefore, this may be an ideal setting to test for impactful interventions aimed at reducing caries and periodontal disease.

Operative Vaginal Delivery Is a Safe Option in Women Undergoing a Trial of Labor after Cesarean

Objective  To compare outcomes of operative intervention in the second stage of labor during trial of labor after cesarean (TOLAC). Study Design  A secondary analysis of the Maternal-Fetal Medicine Units Network cesarean section registry was conducted. Analysis was by first attempted mode of delivery. Results  A total of 1,837 met inclusion criteria. Subjects in the operative vaginal groups (OVDs) were more likely to have a prior vaginal delivery (vacuum 34.2%; forceps 34.3%) than the repeat cesarean delivery (RCD) group (22.6%; p  < 0.0001). Most OVD attempts were successful (forceps 90.4%; vacuum 92.6%). Neonatal morbidity was not different (12.1% forceps vs. 14.6% vacuum; 14.8% RCD). Maternal morbidity was highest among forceps deliveries (32.3 vs. 24.3% vacuum; 22.0% RCD, p  = 0.0001). RCD was associated with surgical injury (2.7 vs. 0.7% forceps; 0% vacuum; p  < 0.0001), endometritis (8.4 vs. 3.2% forceps, 1.2% vacuum; p  < 0.0001), and wound complications (1.9 vs. 0.4% forceps; 0.3% vacuum; p  = 0.006). OVD was associated with anal sphincter laceration (22.7% forceps, 15.5% vacuum; 0% RCD; p  = 0.01). Conclusion  The success rate of OVD is high in TOLAC with similar outcomes to RCD. Maternal composite outcomes were highest with forceps-assisted vaginal deliveries. However, considering overall morbidity, OVD in the second stage of labor in TOLAC is a reasonable, safe option in selected cases.

Qualitative assessment of knowledge transfer regarding preterm birth in Malawi following the implementation of targeted health messages over 3 years

Background

In 2012, we performed a needs assessment and gap analysis to qualitatively assess providers’ and patients’ knowledge and perceptions regarding preterm birth (PTB). During the study, we identified knowledge gaps surrounding methods to reduce the risk of occurrence of PTB and management options if preterm labor/birth occur. We targeted health messages toward these gaps. The objective of the present study was to assess the impact of our community health worker-based patient education program 3 years after it was implemented.

Methods

Fifteen focus groups including 70 participants were included in the study. The groups comprised either patients/patient couples or health providers. A minimum of two facilitators led each group using 22 a priori designed and standardized lead-in prompts for participants with four additional prompts for providers only. A single researcher recorded responses, and transcript notes were reviewed by the facilitators and interpreters immediately following each group discussion to ensure accuracy.

Results

The understanding of term vs preterm gestation was generally accurate. Every participant knew of women who had experienced PTB, and the general perception was that two to three women out of every ten had this experience. The majority of respondents thought that women should present to their local health clinic if they experience preterm contractions; few were aware of the use of antenatal steroids for promoting fetal lung maturity, but many acknowledged that the neonate may be able to receive life-sustaining treatment if born at a higher level of care facility. The majority of participants were aware that PTB could recur in subsequent pregnancies. All respondents were able to list ways that women could potentially reduce the risk of PTB.

Conclusion

After employing targeted health messages, the majority of participants expressed improved understanding of the definition of PTB, methods to prevent risk of PTB, and management options for preterm labor or PTB.

Nutrition and Exercise Strategies to Prevent Excessive Pregnancy Weight Gain: A Meta-analysis

Objective  To evaluate nutrition-only, exercise-only, and nutrition-plus-exercise interventions for optimizing gestational weight gain (GWG) based on the 2009 Institute of Medicine (IOM) guidelines. Study  PubMed, Google Scholar, and 2015 Cochrane Review were searched. Analysis of variance was used to determine if significant GWG differences exist between strategies, with additional subanalyses on overweight (OV) or obese women based on 2009 IOM guidelines. Results  Of 66 identified studies, 31 contributed data ( n  = 8,558). Compared with routine prenatal care, nutrition-only interventions were significantly associated with reduced GWG and are most likely to produce weight gain within IOM recommendations ( p  = 0.013). Exercise-only ( p  = 0.069) and nutrition-plus-exercise ( p  = 0.056) interventions trended toward GWG within IOM guidelines, but did not reach statistical significance. Supervised ( p  = 0.61) and unsupervised ( p  = 0.494) exercise programs had similar effectiveness. Subanalyses on OV or obese women produced similar results to studies that did not differentiate results based on body mass index: nutrition only ( p  = 0.011), exercise only ( p  = 0.308), and nutrition plus exercise ( p  = 0.129). Conclusion  Preventing excessive GWG is crucial, especially for OV or obese women. In the current study, nutrition-based intervention is the health system strategy that showed significant impact on preventing excessive GWG compared with routine prenatal care. Among women who are OV or have obesity, nutrition-only interventions hold the most promise compared with routine prenatal care.

Structured Training for Fetal Diagnostic Skills in a Maternal-Fetal Medicine Fellowship

Objective  The American Institute of Ultrasound in Medicine has described what constitutes a detailed fetal anatomic examination but what comprises an appropriate physician training program has not been described. The purpose of this paper is to describe a highly-structured program developed by our center to train maternal-fetal medicine fellows in a systematic approach to fetal diagnostic imaging. Study Design  We describe this approach in three phases. Phase I: Development of Skills as a Perinatal Sonographer, Phase II: Mentored Evolution to a Perinatal Sonologist and Phase III: Supervised Independent Practice as Consultant-in-training. Results  This curriculum was implemented in 2006. Of the eight maternal-fetal medicine fellows who completed this program, 100% were capable of following this curriculum and 100% felt comfortable performing and interpreting detailed sonograms including sonograms with significant and uncommon anomalies. Qualitative feedback was also positive. Finally, this structured approach resulted in an increase in the average total number of sonograms interpreted. Conclusion  Our curriculum, by following the explicit guidelines and expectations set out by the American Institute of Ultrasound in Medicine and the American Board of Obstetrics and Gynecology for practicing maternal-fetal medicine fellowship graduates, provides an opportunity to explore national standardization for this component of training.

Maternal obesity is not associated with increased crown-rump length in first-trimester ultrasounds of singleton gestations

OBJECTIVE

To evaluate whether or not obesity affects fetal growth in the first trimester of pregnancy.

STUDY DESIGN

A retrospective cohort study of obese versus non-obese women in our ultrasound database was performed to compare crown-rump length (CRL), a surrogate of fetal growth, at the first-trimester genetic screening.

RESULTS

A total of 50 obese and 50 non-obese women were included. CRL for both groups was performed at an average of 12wk5d ± 3 d. A linear regression analysis demonstrated that there was no difference between the cohorts in respect to CRL in the first trimester (p = .482). However, the estimated fetal weight at second-trimester anatomy ultrasound and the neonatal birth weight were increased in obese women (p < .001 for both analyses).

CONCLUSION

Maternal obesity does not significantly alter the fetal CRL. However, maternal obesity appears to be associated with increased fetal growth as early as the second trimester.

Ocular and uteroplacental pathology in a macaque pregnancy with congenital Zika virus infection

Congenital Zika virus (ZIKV) infection impacts fetal development and pregnancy outcomes. We infected a pregnant rhesus macaque with a Puerto Rican ZIKV isolate in the first trimester. The pregnancy was complicated by preterm premature rupture of membranes (PPROM), intraamniotic bacterial infection and fetal demise 49 days post infection (gestational day 95). Significant pathology at the maternal-fetal interface included acute chorioamnionitis, placental infarcts, and leukocytoclastic vasculitis of the myometrial radial arteries. ZIKV RNA was disseminated throughout fetal tissues and maternal immune system tissues at necropsy, as assessed by quantitative RT-PCR for viral RNA. Replicating ZIKV was identified in fetal tissues, maternal uterus, and maternal spleen by fluorescent in situ hybridization for viral replication intermediates. Fetal ocular pathology included a choroidal coloboma, suspected anterior segment dysgenesis, and a dysplastic retina. This is the first report of ocular pathology and prolonged viral replication in both maternal and fetal tissues following congenital ZIKV infection in a rhesus macaque. PPROM followed by fetal demise and severe pathology of the visual system have not been described in macaque congenital ZIKV infection previously. While this case of ZIKV infection during pregnancy was complicated by bacterial infection with PPROM, the role of ZIKV on this outcome cannot be precisely defined, and further nonhuman primate studies will determine if increased risk for PPROM or other adverse pregnancy outcomes are associated with congenital ZIKV infection.

Travel During Pregnancy: Results From an Ultrasound Unit-Based Questionnaire

BACKGROUND

The frequency of domestic and international travel among women residing in the United States, and specifically Wisconsin, during pregnancy is not known. Given the recent epidemic of Zika virus disease, clinicians should be aware of the frequency of travel during pregnancy and should inquire about travel by pregnant women, women of reproductive age, and their sexual partners.

METHODS

Due to the Zika epidemic, our obstetric ultrasound center added questions about international and domestic travel to a general health form that is routinely distributed to all patients presenting for anatomic ultrasounds. The forms were then collected and recorded in order to provide an estimate of the frequency of travel during the first half of pregnancy.

RESULTS

Of 1,256 women screened, 64 (5.1%) traveled internationally and 498 (39.6%) traveled domestically prior to their anatomic ultrasound. Additionally, 77 (6.1%) women screened reported international travel by their sexual partner. Among international travelers, 20 (28.1%) traveled to destinations with active ongoing transmission of Zika virus disease, and 16 (25%) traveled after the Centers for Disease Control and Prevention (CDC) issued a travel alert for the area. Among domestic travelers, Florida was the sixth most common destination, and Texas was the 10th most common.

CONCLUSIONS

In the population of women screened by this questionnaire, 5.1% traveled internationally and 39.6% traveled domestically prior to their anatomic ultrasound. Notably, Florida and Texas are common travel destinations among women at this clinic, and both have had active local transmission of Zika virus.

Highly efficient maternal-fetal Zika virus transmission in pregnant rhesus macaques

Infection with Zika virus (ZIKV) is associated with human congenital fetal anomalies. To model fetal outcomes in nonhuman primates, we administered Asian-lineage ZIKV subcutaneously to four pregnant rhesus macaques. While non-pregnant animals in a previous study contemporary with the current report clear viremia within 10-12 days, maternal viremia was prolonged in 3 of 4 pregnancies. Fetal head growth velocity in the last month of gestation determined by ultrasound assessment of head circumference was decreased in comparison with biparietal diameter and femur length within each fetus, both within normal range. ZIKV RNA was detected in tissues from all four fetuses at term cesarean section. In all pregnancies, neutrophilic infiltration was present at the maternal-fetal interface (decidua, placenta, fetal membranes), in various fetal tissues, and in fetal retina, choroid, and optic nerve (first trimester infection only). Consistent vertical transmission in this primate model may provide a platform to assess risk factors and test therapeutic interventions for interruption of fetal infection. The results may also suggest that maternal-fetal ZIKV transmission in human pregnancy may be more frequent than currently appreciated.

Under Pressure: Intraluminal Filling Pressures of Postpartum Hemorrhage Tamponade Balloons

Objective Uterine tamponade by fluid-filled balloons is now an accepted method of controlling postpartum hemorrhage. Available tamponade balloons vary in design and material, which affects the filling attributes and volume at which they rupture. We aimed to characterize the filling capacity and pressure-volume relationship of various tamponade balloons. Study Design Balloons were filled with water ex vivo. Intraluminal pressure was measured incrementally (every 10 mL for the Foley balloons and every 50 mL for all other balloons). Balloons were filled until they ruptured or until 5,000 mL was reached. Results The Foley balloons had higher intraluminal pressures than the larger-volume balloons. The intraluminal pressure of the Sengstaken-Blakemore tube (gastric balloon) was initially high, but it decreased until shortly before rupture occurred. The Bakri intraluminal pressure steadily increased until rupture occurred at 2,850 mL. The condom catheter, BT-Cath, and ebb all had low intraluminal pressures. Both the BT-Cath and the ebb remained unruptured at 5,000 mL. Conclusion In the setting of acute hemorrhage, expeditious management is critical. Balloons that have a low intraluminal pressure-volume ratio may fill more rapidly, more easily, and to greater volumes. We found that the BT-Cath, the ebb, and the condom catheter all had low intraluminal pressures throughout filling.