Clinical risk factors of adverse outcomes among women with COVID-19 in the pregnancy and postpartum period: a sequential, prospective meta-analysis

OBJECTIVE

This sequential, prospective meta-analysis sought to identify risk factors among pregnant and postpartum women with COVID-19 for adverse outcomes related to disease severity, maternal morbidities, neonatal mortality and morbidity, and adverse birth outcomes.

DATA SOURCES

We prospectively invited study investigators to join the sequential, prospective meta-analysis via professional research networks beginning in March 2020.

STUDY ELIGIBILITY CRITERIA

Eligible studies included those recruiting at least 25 consecutive cases of COVID-19 in pregnancy within a defined catchment area.

METHODS

We included individual patient data from 21 participating studies. Data quality was assessed, and harmonized variables for risk factors and outcomes were constructed. Duplicate cases were removed. Pooled estimates for the absolute and relative risk of adverse outcomes comparing those with and without each risk factor were generated using a 2-stage meta-analysis.

RESULTS

We collected data from 33 countries and territories, including 21,977 cases of SARS-CoV-2 infection in pregnancy or postpartum. We found that women with comorbidities (preexisting diabetes mellitus, hypertension, cardiovascular disease) vs those without were at higher risk for COVID-19 severity and adverse pregnancy outcomes (fetal death, preterm birth, low birthweight). Participants with COVID-19 and HIV were 1.74 times (95% confidence interval, 1.12-2.71) more likely to be admitted to the intensive care unit. Pregnant women who were underweight before pregnancy were at higher risk of intensive care unit admission (relative risk, 5.53; 95% confidence interval, 2.27-13.44), ventilation (relative risk, 9.36; 95% confidence interval, 3.87-22.63), and pregnancy-related death (relative risk, 14.10; 95% confidence interval, 2.83-70.36). Prepregnancy obesity was also a risk factor for severe COVID-19 outcomes including intensive care unit admission (relative risk, 1.81; 95% confidence interval, 1.26-2.60), ventilation (relative risk, 2.05; 95% confidence interval, 1.20-3.51), any critical care (relative risk, 1.89; 95% confidence interval, 1.28-2.77), and pneumonia (relative risk, 1.66; 95% confidence interval, 1.18-2.33). Anemic pregnant women with COVID-19 also had increased risk of intensive care unit admission (relative risk, 1.63; 95% confidence interval, 1.25-2.11) and death (relative risk, 2.36; 95% confidence interval, 1.15-4.81).

CONCLUSION

We found that pregnant women with comorbidities including diabetes mellitus, hypertension, and cardiovascular disease were at increased risk for severe COVID-19-related outcomes, maternal morbidities, and adverse birth outcomes. We also identified several less commonly known risk factors, including HIV infection, prepregnancy underweight, and anemia. Although pregnant women are already considered a high-risk population, special priority for prevention and treatment should be given to pregnant women with these additional risk factors.

Adverse maternal, fetal, and newborn outcomes among pregnant women with SARS-CoV-2 infection: an individual participant data meta-analysis

INTRODUCTION

Despite a growing body of research on the risks of SARS-CoV-2 infection during pregnancy, there is continued controversy given heterogeneity in the quality and design of published studies.

METHODS

We screened ongoing studies in our sequential, prospective meta-analysis. We pooled individual participant data to estimate the absolute and relative risk (RR) of adverse outcomes among pregnant women with SARS-CoV-2 infection, compared with confirmed negative pregnancies. We evaluated the risk of bias using a modified Newcastle-Ottawa Scale.

RESULTS

We screened 137 studies and included 12 studies in 12 countries involving 13 136 pregnant women.Pregnant women with SARS-CoV-2 infection-as compared with uninfected pregnant women-were at significantly increased risk of maternal mortality (10 studies; n=1490; RR 7.68, 95% CI 1.70 to 34.61); admission to intensive care unit (8 studies; n=6660; RR 3.81, 95% CI 2.03 to 7.17); receiving mechanical ventilation (7 studies; n=4887; RR 15.23, 95% CI 4.32 to 53.71); receiving any critical care (7 studies; n=4735; RR 5.48, 95% CI 2.57 to 11.72); and being diagnosed with pneumonia (6 studies; n=4573; RR 23.46, 95% CI 3.03 to 181.39) and thromboembolic disease (8 studies; n=5146; RR 5.50, 95% CI 1.12 to 27.12).Neonates born to women with SARS-CoV-2 infection were more likely to be admitted to a neonatal care unit after birth (7 studies; n=7637; RR 1.86, 95% CI 1.12 to 3.08); be born preterm (7 studies; n=6233; RR 1.71, 95% CI 1.28 to 2.29) or moderately preterm (7 studies; n=6071; RR 2.92, 95% CI 1.88 to 4.54); and to be born low birth weight (12 studies; n=11 930; RR 1.19, 95% CI 1.02 to 1.40). Infection was not linked to stillbirth. Studies were generally at low or moderate risk of bias.

CONCLUSIONS

This analysis indicates that SARS-CoV-2 infection at any time during pregnancy increases the risk of maternal death, severe maternal morbidities and neonatal morbidity, but not stillbirth or intrauterine growth restriction. As more data become available, we will update these findings per the published protocol.

Protocol for a sequential, prospective meta-analysis to describe coronavirus disease 2019 (COVID-19) in the pregnancy and postpartum periods

We urgently need answers to basic epidemiological questions regarding SARS-CoV-2 infection in pregnant and postpartum women and its effect on their newborns. While many national registries, health facilities, and research groups are collecting relevant data, we need a collaborative and methodologically rigorous approach to better combine these data and address knowledge gaps, especially those related to rare outcomes. We propose that using a sequential, prospective meta-analysis (PMA) is the best approach to generate data for policy- and practice-oriented guidelines. As the pandemic evolves, additional studies identified retrospectively by the steering committee or through living systematic reviews will be invited to participate in this PMA. Investigators can contribute to the PMA by either submitting individual patient data or running standardized code to generate aggregate data estimates. For the primary analysis, we will pool data using two-stage meta-analysis methods. The meta-analyses will be updated as additional data accrue in each contributing study and as additional studies meet study-specific time or data accrual thresholds for sharing. At the time of publication, investigators of 25 studies, including more than 76,000 pregnancies, in 41 countries had agreed to share data for this analysis. Among the included studies, 12 have a contemporaneous comparison group of pregnancies without COVID-19, and four studies include a comparison group of non-pregnant women of reproductive age with COVID-19. Protocols and updates will be maintained publicly. Results will be shared with key stakeholders, including the World Health Organization (WHO) Maternal, Newborn, Child, and Adolescent Health (MNCAH) Research Working Group. Data contributors will share results with local stakeholders. Scientific publications will be published in open-access journals on an ongoing basis.

Open intrauterine repair of spina bifida aperta: Historical aspects, current availability, and clinical outcomes from the Latin American Spina Bifida Consortium

OBJECTIVE

To determine the historical aspects, current availability, and clinical outcomes of open intrauterine repair of spina bifida aperta (IRSBA) in Spanish-speaking Latin American countries.

METHODS

Cases were collected from centers with at least 2 years of experience and a minimum of 10 open IRSBA interventions by December 2020. Clinical variables were compared to the results of the Management of Myelomeningocele Study (MOMS) trial.

RESULTS

Clinical experience with 314 cases from seven centers was reviewed. Most cases (n = 189, 60.2%) were performed between 24 and 25.9 weeks' gestation. Delivery at less than 30 weeks' gestation occurred in 36 cases (11.5%) and the overall perinatal mortality rate was 5.4% (17 of 314). The rate of maternal complications was low, including the need for blood transfusion (n = 3, 0.9%) and dehiscence or a thin uterine scar (n = 4, 1.3%). No cases of maternal death were recorded. Fifteen neonates required additional surgical repair of the spinal defect (4.8%) and 63 of 167 infants (37.7%) required a cerebrospinal fluid diversion procedure. Only two of the seven centers reported preliminary experience with fetoscopic IRSBA.

CONCLUSIONS

Clinical experience and outcomes were within the expected results reported by the MOMS trial. There is still very limited experience with fetoscopic IRSBA in this part of the world.

Pregnancy and catastrophic antiphospholipid syndrome

Antiphospholipid syndrome (APS) is clearly related to maternal morbidity. The most characteristic feature is pregnancy loss; however, several other serious complications had been reported including fetal growth restriction, uteroplacental insufficiency, fetal distress, pre-eclampsia, and HELLP syndrome. Herein, we review the different aspects of obstetric APS features, with special emphasis on its life-threatening variant known as catastrophic APS (Asherson's syndrome) and its relationship with a thrombotic microangiopathy such as HELLP syndrome.

The use of a variable cut-off value of cervical length in women admitted for preterm labor before and after 32 weeks

OBJECTIVE

To determine whether the optimal cut-off value to predict low risk of preterm delivery in women admitted for preterm labor should be adjusted for gestational age.

METHODS

A cohort of 333 women with singleton pregnancies admitted with preterm labor and intact membranes between 24 and < 36 weeks' gestation was studied. The women were categorized according to prematurity into one of two groups: those admitted at < 32 weeks (Group 1, very preterm) and those admitted at >or= 32 weeks (Group 2, preterm). Transvaginal ultrasound was performed 24-48 h after admission and cervical length measured. The predictive value of different cut-off points was explored. Outcome variables were spontaneous preterm delivery within 7 days of admission and delivery at < 34 weeks.

RESULTS

The mean ( +/- SD) gestational ages at admission and delivery were 31.9 ( +/- 2.6) and 37.5 ( +/- 2.2) weeks, respectively, and the mean ( +/- SD) cervical length was 30.4 ( +/- 8.9) mm. The rates of spontaneous delivery within 7 days and at < 34 weeks were 6.3 and 7.0%, respectively. The cut-off value of 15-mm cervical length showed a sensitivity, negative predictive value and false positive rate for delivery within 7 days of 0, 96.5 and 2.7% in the very preterm group, and 35.3, 94.6 and 4% in the preterm group, respectively. For a cut-off point of 25 mm, these values were 75, 99 and 14.3%, and 70.6, 96.8 and 24.5%.

CONCLUSIONS

The predictive value of different cut-off points of cervical length is similar at different gestational ages. However, the higher false positive rate after 32 weeks' gestation might justify the adoption of gestational-age related cut-off values in clinical protocols. In women admitted at < 32 weeks' gestation, a cut-off point of 25 mm may be used to predict a low risk of preterm delivery, whereas in women admitted at 32 weeks or later, 15 mm might be more appropriate. Published by John Wiley & Sons, Ltd.

A modified myocardial performance (Tei) index based on the use of valve clicks improves reproducibility of fetal left cardiac function assessment

OBJECTIVE

To determine whether a modified myocardial performance index (Mod-MPI) involving assessment of the movements (clicks) of the mitral valve (MV) and aortic valve (AV), improves intra- and interobserver agreement as compared to the previously reported method for MPI estimation.

METHODS

The Mod-MPI was recorded by two experienced operators in the left cardiac chambers of 25 normally grown fetuses using pulsed Doppler ultrasonography. The isovolumetric contraction time (ICT) was measured from the closure of the MV to the opening of the AV, the ejection time (ET) from the opening to the closure of the AV, and the isovolumetric relaxation time (IRT) from the closure of the AV to the opening of the MV. The Mod-MPI was calculated as (ICT + IRT)/ET. In addition, the MPI was estimated without using the valve clicks (F-MPI) as previously described. Intra- and interobserver agreement were then analyzed for both modalities.

RESULTS

There was a significantly lower intra- and inter-observer variability in the estimation of all time periods with the Mod-MPI than with the F-MPI (ICT: intra-observer, 9.9% vs. 13.9%; interobserver 9.9% vs. 15.6%; IRT: intraobserver, 9.9% vs. 14.8%; interobserver 10.4% vs. 18.3%; and ET: intraobserver, 4.5% vs. 6.1%; interobserver 2.8% vs. 5.2%, respectively). Intraclass correlation coefficient (IntraCC) for the Mod-MPI was 0.8 (95% confidence interval (95% CI), 0.56-0.9) and for the F-MPI, the IntraCC was 0.62 (95% CI, 0.26-0.84); P = 0.01. Agreement between observers using the Mod-MPI showed a mean difference of 0.0 with 95% limits of agreement (LA) -0.09 (95% CI, -0.1 to -0.075) to 0.09 (95% CI, 0.075-0.1) and for the F-MPI the mean difference was -0.01 with 95% LA -0.26 (95% CI, -0.3 to -0.22) to 0.25 (95% CI, 0.21-0.29).

CONCLUSION

Calculation of the Mod-MPI based on Doppler echoes of the MV and AV clicks is associated with a lower variation and better inter- and intraobserver agreement than the previously used method for fetal cardiac evaluation.

A histological study of fetoscopic membrane defects to document membrane healing

OBJECTIVE

To evaluate the rate of spontaneous healing in human fetal membranes after fetoscopy.

STUDY DESIGN

Membranes from patients that had undergone fetoscopic interventions and delivered in one of the two treatment centers were included in the study. The membranes were examined macroscopically for any remaining defects and if present, the size of the defect in chorion and amnion was measured. Subsequently, the defect was excised and stained with HE for histological evaluation. Additional immunohistochemical staining was performed with Ki-67, cytokeratin and vimentin. The proliferation index (percentage of proliferating cells) was calculated in amnion and chorion.

RESULTS

Nineteen membrane defects were included in the study. The median time interval between invasive procedures and delivery was 60 days (range 3-112). All fetoscopic defects (n=19) could be identified in the gestational sac and in none spontaneous closure had occurred. Proliferation indices as measured by inmunohistochemistry were very low (median 2.8%, range 0-7%) in the chorion and 0% in the amnion.

CONCLUSION

No evidence of spontaneous membrane healing was found after fetoscopic procedures, suggesting that the membrane defect normally persists until delivery. Absence of amniotic fluid leakage after invasive procedures may be based on mechanisms other than histologic membrane repair.

Impact of ultrasound cervical length assessment on duration of hospital stay in the clinical management of threatened preterm labor

OBJECTIVE

To evaluate the impact of ultrasound cervical length measurement on duration of hospital stay in patients admitted for threatened preterm labor.

STUDY DESIGN

This was a prospective, comparative study in 294 patients with threatened preterm labor in three hospitalization units (Units A, B and C). In the first phase of the study (observational), cervical length was measured by transvaginal ultrasound, but managing physicians were blinded to the results. In the second phase (interventional), physicians from Unit A remained blinded to cervical length information, but Units B and C incorporated these data into their clinical management protocols. Early discharge was contemplated if the cervix measured 25 mm or more on admission (Unit B) or no changes were observed over 48 h (Unit C). Duration of hospital stay and delivery rates within 7 days and before 37 weeks' gestation were recorded.

RESULTS

Hospital stay was significantly reduced in Units B and C in the interventional phase, while no changes were observed in Unit A. Delivery rates within 7 days and before 37 weeks' gestation were similar in the three units during the two stages of the study.

CONCLUSION

Routine use of ultrasound cervical length assessment in patients admitted with threatened preterm labor may reduce the duration of hospital stay without increasing the rate of preterm births. These data should be confirmed by means of an appropriately designed randomized clinical trial.