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Sascha R Ellington - Top 30 Publications

Update: Interim Guidance for Health Care Providers Caring for Pregnant Women with Possible Zika Virus Exposure - United States (Including U.S. Territories), July 2017.

CDC has updated the interim guidance for U.S. health care providers caring for pregnant women with possible Zika virus exposure in response to 1) declining prevalence of Zika virus disease in the World Health Organization's Region of the Americas (Americas) and 2) emerging evidence indicating prolonged detection of Zika virus immunoglobulin M (IgM) antibodies. Zika virus cases were first reported in the Americas during 2015-2016; however, the incidence of Zika virus disease has since declined. As the prevalence of Zika virus disease declines, the likelihood of false-positive test results increases. In addition, emerging epidemiologic and laboratory data indicate that, as is the case with other flaviviruses, Zika virus IgM antibodies can persist beyond 12 weeks after infection. Therefore, IgM test results cannot always reliably distinguish between an infection that occurred during the current pregnancy and one that occurred before the current pregnancy, particularly for women with possible Zika virus exposure before the current pregnancy. These limitations should be considered when counseling pregnant women about the risks and benefits of testing for Zika virus infection during pregnancy. This updated guidance emphasizes a shared decision-making model for testing and screening pregnant women, one in which patients and providers work together to make decisions about testing and care plans based on patient preferences and values, clinical judgment, and a balanced assessment of risks and expected outcomes.

Trends in Diagnoses Among Hospitalizations of HIV-infected Children and Adolescents in the United States: 2003-2012.

Using data from 2003-2012, we updated a previous analysis of trends in hospitalizations of HIV-infected children and adolescents in the United States.

Pregnancy Outcomes After Maternal Zika Virus Infection During Pregnancy - U.S. Territories, January 1, 2016-April 25, 2017.

Pregnant women living in or traveling to areas with local mosquito-borne Zika virus transmission are at risk for Zika virus infection, which can lead to severe fetal and infant brain abnormalities and microcephaly (1). In February 2016, CDC recommended 1) routine testing for Zika virus infection of asymptomatic pregnant women living in areas with ongoing local Zika virus transmission at the first prenatal care visit, 2) retesting during the second trimester for women who initially test negative, and 3) testing of pregnant women with signs or symptoms consistent with Zika virus disease (e.g., fever, rash, arthralgia, or conjunctivitis) at any time during pregnancy (2). To collect information about pregnant women with laboratory evidence of recent possible Zika virus infection* and outcomes in their fetuses and infants, CDC established pregnancy and infant registries (3). During January 1, 2016-April 25, 2017, U.S. territories(†) with local transmission of Zika virus reported 2,549 completed pregnancies(§) (live births and pregnancy losses at any gestational age) with laboratory evidence of recent possible Zika virus infection; 5% of fetuses or infants resulting from these pregnancies had birth defects potentially associated with Zika virus infection(¶) (4,5). Among completed pregnancies with positive nucleic acid tests confirming Zika infection identified in the first, second, and third trimesters, the percentage of fetuses or infants with possible Zika-associated birth defects was 8%, 5%, and 4%, respectively. Among liveborn infants, 59% had Zika laboratory testing results reported to the pregnancy and infant registries. Identification and follow-up of infants born to women with laboratory evidence of recent possible Zika virus infection during pregnancy permits timely and appropriate clinical intervention services (6).

Measures Taken to Prevent Zika Virus Infection During Pregnancy - Puerto Rico, 2016.

Zika virus infection during pregnancy remains a serious health threat in Puerto Rico. Infection during pregnancy can cause microcephaly, brain abnormalities, and other severe birth defects (1). From January 1, 2016 through March 29, 2017, Puerto Rico reported approximately 3,300 pregnant women with laboratory evidence of possible Zika virus infection (2). There is currently no vaccine or intervention to prevent the adverse effects of Zika virus infection during pregnancy; therefore, prevention has been the focus of public health activities, especially for pregnant women (3). CDC and the Puerto Rico Department of Health analyzed data from the Pregnancy Risk Assessment Monitoring System Zika Postpartum Emergency Response (PRAMS-ZPER) survey conducted from August through December 2016 among Puerto Rico residents with a live birth. Most women (98.1%) reported using at least one measure to avoid mosquitos in their home environment. However, only 45.8% of women reported wearing mosquito repellent daily, and 11.5% reported wearing pants and shirts with long sleeves daily. Approximately one third (38.5%) reported abstaining from sex or using condoms consistently throughout pregnancy. Overall, 76.9% of women reported having been tested for Zika virus by their health care provider during the first or second trimester of pregnancy. These results can be used to assess and refine Zika virus infection prevention messaging and interventions for pregnant women and to reinforce measures to promote prenatal testing for Zika.

Vital Signs: Update on Zika Virus-Associated Birth Defects and Evaluation of All U.S. Infants with Congenital Zika Virus Exposure - U.S. Zika Pregnancy Registry, 2016.

In collaboration with state, tribal, local, and territorial health departments, CDC established the U.S. Zika Pregnancy Registry (USZPR) in early 2016 to monitor pregnant women with laboratory evidence of possible recent Zika virus infection and their infants.

Baseline Prevalence of Birth Defects Associated with Congenital Zika Virus Infection - Massachusetts, North Carolina, and Atlanta, Georgia, 2013-2014.

Zika virus infection during pregnancy can cause serious brain abnormalities, but the full range of adverse outcomes is unknown (1). To better understand the impact of birth defects resulting from Zika virus infection, the CDC surveillance case definition established in 2016 for birth defects potentially related to Zika virus infection* (2) was retrospectively applied to population-based birth defects surveillance data collected during 2013-2014 in three areas before the introduction of Zika virus (the pre-Zika years) into the World Health Organization's Region of the Americas (Americas) (3). These data, from Massachusetts (2013), North Carolina (2013), and Atlanta, Georgia (2013-2014), included 747 infants and fetuses with one or more of the birth defects meeting the case definition (pre-Zika prevalence = 2.86 per 1,000 live births). Brain abnormalities or microcephaly were the most frequently recorded (1.50 per 1,000), followed by neural tube defects and other early brain malformations(†) (0.88), eye abnormalities without mention of a brain abnormality (0.31), and other consequences of central nervous system (CNS) dysfunction without mention of brain or eye abnormalities (0.17). During January 15-September 22, 2016, the U.S. Zika Pregnancy Registry (USZPR) reported 26 infants and fetuses with these same defects among 442 completed pregnancies (58.8 per 1,000) born to mothers with laboratory evidence of possible Zika virus infection during pregnancy (2). Although the ascertainment methods differed, this finding was approximately 20 times higher than the proportion of one or more of the same birth defects among pregnancies during the pre-Zika years. These data demonstrate the importance of population-based surveillance for interpreting data about birth defects potentially related to Zika virus infection.

Birth Defects Among Fetuses and Infants of US Women With Evidence of Possible Zika Virus Infection During Pregnancy.

Understanding the risk of birth defects associated with Zika virus infection during pregnancy may help guide communication, prevention, and planning efforts. In the absence of Zika virus, microcephaly occurs in approximately 7 per 10 000 live births.

Maternal and Breastmilk Viral Load: Impacts of Adherence on Peripartum HIV Infections Averted-The Breastfeeding, Antiretrovirals, and Nutrition Study.

Antiretroviral (ARV) interventions are used to reduce HIV viral replication and prevent mother-to-child transmission. Viral suppression relies on adherence to ARVs.

CDC Online Course: Reproductive Health in Emergency Preparedness and Response.

In an emergency, the needs of women of reproductive age, particularly pregnant and postpartum women, introduce unique challenges for public health and clinical care. Incorporating reproductive health issues and considerations into emergency preparedness and response is a relatively new field. In recent years, several resources and tools specific to reproductive health have been developed. However, there is still a need for training about the effects of emergencies on women of reproductive age. In an effort to train medical and public health professionals about these topics, the CDC Division of Reproductive Health developed Reproductive Health in Emergency Preparedness and Response, an online course that is available across the United States.

Estimating the Number of Pregnant Women Infected With Zika Virus and Expected Infants With Microcephaly Following the Zika Virus Outbreak in Puerto Rico, 2016.

Zika virus (ZIKV) infection during pregnancy is a cause of congenital microcephaly and severe fetal brain defects, and it has been associated with other adverse pregnancy and birth outcomes.

Full-Term Small-for-Gestational-Age Newborns in the U.S.: Characteristics, Trends, and Morbidity.

Objectives The magnitude, characteristics, and morbidity of term (≥37 weeks gestation) newborns that are small-for-gestational-age (SGA) in the U.S. are underexplored. We sought to examine characteristics and trends for SGA-coded term newborns in the U.S. Methods Data were obtained from the Nationwide Inpatient Sample, a nationally representative database of hospital stays in the U.S. from 2002 to 2011. Term, singleton newborns with SGA codes were identified and examined over the study period. Demographic characteristics were compared for term newborns according to presence of SGA codes using χ(2) tests. Odds ratios (OR) were calculated to compare morbidities between the two groups, adjusting for relevant demographic and clinical variables. Results In 2011, 15 per 1000 term newborns in the U.S. were coded as SGA, a 29.9 % increase since 2002. Compared with other term newborns, SGA term newborns were significantly (p < 0.05) more likely to be female, receive public insurance, and reside in lower income zip codes. Comorbidities, including perinatal complications, metabolic disorders, central nervous system diseases, infection, and neonatal abstinence syndrome were more common among SGA-coded term newborns. These newborns also had higher odds of in-hospital death (OR = 3.0 95 % confidence interval: 2.0, 4.4), longer mean length of stay (3.7 vs. 2.3 days, p < 0.001), and higher mean hospital charges ($12,621 vs. $5012, p < 0.001). Conclusions for practice Term newborns coded as SGA have higher morbidity, mortality, and incur higher hospital charges than other term newborns. More research is needed to understand causes of SGA so its incidence and effects can be reduced.

Trends in hospitalizations of pregnant HIV-infected women in the United States: 2004 through 2011.

With the development and widespread use of combination antiretroviral therapy, HIV-infected women live longer, healthier lives. Previous research has shown that, since the adoption of combination antiretroviral therapy in the United States, rates of morbidity and adverse obstetric outcomes remained higher for HIV-infected pregnant women compared with HIV-uninfected pregnant women. Monitoring trends in the outcomes these women experience is essential, as recommendations for this special population continue to evolve with the progress of HIV treatment and prevention options.

Update: Interim Guidance for Health Care Providers Caring for Women of Reproductive Age with Possible Zika Virus Exposure--United States, 2016.

CDC has updated its interim guidance for U.S. health care providers caring for women of reproductive age with possible Zika virus exposure to include recommendations on counseling women and men with possible Zika virus exposure who are interested in conceiving. This guidance is based on limited available data on persistence of Zika virus RNA in blood and semen. Women who have Zika virus disease should wait at least 8 weeks after symptom onset to attempt conception, and men with Zika virus disease should wait at least 6 months after symptom onset to attempt conception. Women and men with possible exposure to Zika virus but without clinical illness consistent with Zika virus disease should wait at least 8 weeks after exposure to attempt conception. Possible exposure to Zika virus is defined as travel to or residence in an area of active Zika virus transmission (, or sex (vaginal intercourse, anal intercourse, or fellatio) without a condom with a man who traveled to or resided in an area of active transmission. Women and men who reside in areas of active Zika virus transmission should talk with their health care provider about attempting conception. This guidance also provides updated recommendations on testing of pregnant women with possible Zika virus exposure. These recommendations will be updated when additional data become available.

Zika Virus and Pregnancy: What Obstetric Health Care Providers Need to Know.

Zika virus is a flavivirus transmitted by Aedes (Stegomyia) species of mosquitoes. In May 2015, the World Health Organization confirmed the first local transmission of Zika virus in the Americas in Brazil. The virus has spread rapidly to other countries in the Americas; as of January 29, 2016, local transmission has been detected in at least 22 countries or territories, including the Commonwealth of Puerto Rico and the U.S. Virgin Islands. Zika virus can infect pregnant women in all three trimesters. Although pregnant women do not appear to be more susceptible to or more severely affected by Zika virus infection, maternal-fetal transmission has been documented. Several pieces of evidence suggest that maternal Zika virus infection is associated with adverse neonatal outcomes, most notably microcephaly. Because of the number of countries and territories with local Zika virus transmission, it is likely that obstetric health care providers will care for pregnant women who live in or have traveled to an area of local Zika virus transmission. We review information on Zika virus, its clinical presentation, modes of transmission, laboratory testing, effects during pregnancy, and methods of prevention to assist obstetric health care providers in caring for pregnant women considering travel or with a history of travel to areas with ongoing Zika virus transmission and pregnant women residing in areas with ongoing Zika virus transmission.

Thiamin and Riboflavin in Human Milk: Effects of Lipid-Based Nutrient Supplementation and Stage of Lactation on Vitamer Secretion and Contributions to Total Vitamin Content.

While thiamin and riboflavin in breast milk have been analyzed for over 50 years, less attention has been given to the different forms of each vitamin. Thiamin-monophosphate (TMP) and free thiamin contribute to total thiamin content; flavin adenine-dinucleotide (FAD) and free riboflavin are the main contributors to total riboflavin. We analyzed milk collected at 2 (n = 258) or 6 (n = 104), and 24 weeks (n = 362) from HIV-infected Malawian mothers within the Breastfeeding, Antiretrovirals and Nutrition (BAN) study, randomly assigned at delivery to lipid-based nutrient supplements (LNS) or a control group, to investigate each vitamer's contribution to total milk vitamin content and the effects of supplementation on the different thiamin and riboflavin vitamers at early and later stages of lactation, and obtain insight into the transport and distribution of these vitamers in human milk. Thiamin vitamers were derivatized into thiochrome-esters and analyzed by high-performance liquid-chromatography-fluorescence-detection (HPLC-FLD). Riboflavin and FAD were analyzed by ultra-performance liquid-chromatography-tandem-mass-spectrometry (ULPC-MS/MS). Thiamin-pyrophosphate (TPP), identified here for the first time in breast milk, contributed 1.9-4.5% to total thiamin. Free thiamin increased significantly from 2/6 to 24 weeks regardless of treatment indicating an active transport of this vitamer in milk. LNS significantly increased TMP and free thiamin only at 2 weeks compared to the control: median 170 versus 151 μg/L (TMP), 13.3 versus 10.5 μg/L (free thiamin, p<0.05 for both, suggesting an up-regulated active mechanism for TMP and free thiamin accumulation at early stages of lactation. Free riboflavin was consistently and significantly increased with LNS (range: 14.8-19.6 μg/L (LNS) versus 5.0-7.4 μg/L (control), p<0.001), shifting FAD:riboflavin relative amounts from 92-94:6-8% to 85:15%, indicating a preferred secretion of the free form into breast milk. The continuous presence of FAD in breast milk suggests an active transport and secretion system for this vitamer or possibly formation of this co-enymatic form in the mammary gland.

Update: Interim Guidelines for Health Care Providers Caring for Pregnant Women and Women of Reproductive Age with Possible Zika Virus Exposure - United States, 2016.

CDC has updated its interim guidelines for U.S. health care providers caring for pregnant women during a Zika virus outbreak (1). Updated guidelines include a new recommendation to offer serologic testing to asymptomatic pregnant women (women who do not report clinical illness consistent with Zika virus disease) who have traveled to areas with ongoing Zika virus transmission. Testing can be offered 2-12 weeks after pregnant women return from travel. This update also expands guidance to women who reside in areas with ongoing Zika virus transmission, and includes recommendations for screening, testing, and management of pregnant women and recommendations for counseling women of reproductive age (15-44 years). Pregnant women who reside in areas with ongoing Zika virus transmission have an ongoing risk for infection throughout their pregnancy. For pregnant women with clinical illness consistent with Zika virus disease,* testing is recommended during the first week of illness. For asymptomatic pregnant women residing in areas with ongoing Zika virus transmission, testing is recommended at the initiation of prenatal care with follow-up testing mid-second trimester. Local health officials should determine when to implement testing of asymptomatic pregnant women based on information about levels of Zika virus transmission and laboratory capacity. Health care providers should discuss reproductive life plans, including pregnancy intention and timing, with women of reproductive age in the context of the potential risks associated with Zika virus infection.

Interim Guidelines for Pregnant Women During a Zika Virus Outbreak--United States, 2016.

CDC has developed interim guidelines for health care providers in the United States caring for pregnant women during a Zika virus outbreak. These guidelines include recommendations for pregnant women considering travel to an area with Zika virus transmission and recommendations for screening, testing, and management of pregnant returning travelers. Updates on areas with ongoing Zika virus transmission are available online ( Health care providers should ask all pregnant women about recent travel. Pregnant women with a history of travel to an area with Zika virus transmission and who report two or more symptoms consistent with Zika virus disease (acute onset of fever, maculopapular rash, arthralgia, or conjunctivitis) during or within 2 weeks of travel, or who have ultrasound findings of fetal microcephaly or intracranial calcifications, should be tested for Zika virus infection in consultation with their state or local health department. Testing is not indicated for women without a travel history to an area with Zika virus transmission. In pregnant women with laboratory evidence of Zika virus infection, serial ultrasound examination should be considered to monitor fetal growth and anatomy and referral to a maternal-fetal medicine or infectious disease specialist with expertise in pregnancy management is recommended. There is no specific antiviral treatment for Zika virus; supportive care is recommended.

Cytomegalovirus Infection in Human Immunodeficiency Virus (HIV)-Exposed and HIV-Infected Infants: A Systematic Review.

Cytomegalovirus is highly prevalent worldwide and an important opportunistic pathogen in human immunodeficiency virus (HIV)-infected individuals. The effects of cytomegalovirus infection on HIV-exposed infants are poorly understood. We conducted a systematic review to assess the relationship between cytomegalovirus and HIV infections among HIV-exposed infants. Limited evidence suggests that HIV-induced immunosuppression in the mother increases the rate of congenital cytomegalovirus infection, while maternal antiretroviral therapy may reduce it. Limited information exists on the direction of the relationship between cytomegalovirus and HIV transmission among HIV-exposed infants. Only 2 studies have addressed this temporal sequence of events, and they suggest that cytomegalovirus can lead to subsequent HIV infection in HIV-exposed infants. Most evidence suggests that early cytomegalovirus infection accelerates HIV disease progression in infants. Gaps remain in understanding the role that cytomegalovirus infection plays in HIV-exposed infants. Decreasing cytomegalovirus transmission prenatally and in infancy might further decrease HIV transmission and lead to better health among HIV-exposed infants.

Impact of daily cotrimoxazole on clinical malaria and asymptomatic parasitemias in HIV-exposed, uninfected infants.

Cotrimoxazole preventive therapy (CPT) is recommended for all human immunodeficiency virus (HIV)-exposed infants to avoid opportunistic infections. Cotrimoxazole has antimalarial effects and appears to reduce clinical malaria infections, but the impact on asymptomatic malaria infections is unknown.

Antiretroviral Treatment Is Associated With Iron Deficiency in HIV-Infected Malawian Women That Is Mitigated With Supplementation, but Is Not Associated With Infant Iron Deficiency During 24 Weeks of Exclusive Breastfeeding.

In resource-limited settings without safe alternatives to breastfeeding, the WHO recommends exclusive breastfeeding and antiretroviral (ARV) prophylaxis. Given the high prevalence of anemia among HIV-infected women, mothers and their infants (through fetal iron accretion) may be at risk of iron deficiency. We assessed the effects of maternal micronutrient-fortified lipid-based nutrient supplements (LNS) and maternal ARV treatment or infant ARV prophylaxis on maternal and infant iron status during exclusive breastfeeding from birth to 24 weeks.

Adherence to extended postpartum antiretrovirals is associated with decreased breast milk HIV-1 transmission.

Estimate association between postpartum antiretroviral adherence and breast milk HIV-1 transmission.

Recent trends in hepatic diseases during pregnancy in the United States, 2002-2010.

While pregnancy-related severe liver disorders are rare, when they occur morbidity and mortality rates are increased for mothers and infants. The objective of this study was to examine the prevalence and trends of hepatic diseases during pregnancy hospitalizations from 2002 through 2010 in the United States.

Antiretroviral pharmacokinetics in mothers and breastfeeding infants from 6 to 24 weeks post-partum: results of the BAN Study.

An intensive, prospective, open-label pharmacokinetic (PK) study in a subset of HIV-infected mothers and their uninfected infants enrolled in the Breastfeeding, Antiretroviral and Nutrition (BAN) Study was performed to describe drug exposure and antiviral response.

Health outcomes of HIV-exposed uninfected African infants.

To evaluate severe (grade 3/4) morbidity and mortality in HIV-exposed, uninfected infants.

Maternal weight loss during exclusive breastfeeding is associated with reduced weight and length gain in daughters of HIV-infected Malawian women.

Maternal weight loss during exclusive breastfeeding may influence the growth of exclusively breast-fed infants through impaired quality or quantity of breast milk. This study evaluated how maternal weight loss from 2 to 24 wk postpartum was related to infant weight and length gain in 1309 lactating HIV-infected mothers and their exclusively breast-fed infants. Malawian mother-infant pairs in the Breastfeeding, Antiretrovirals, and Nutrition Study were randomized with a 2 × 3 factorial design to a 2-arm nutritional intervention with a lipid-based nutrient supplement (LNS), meeting nutritional needs of lactation, or no LNS and a 3-arm antiretroviral (ARV) intervention (maternal, infant, or no ARV regimen). Linear regression models were used to relate maternal weight loss (weight loss vs. no weight loss) to infant weight and length gain from birth to 24 mo, stratifying by gender and controlling for maternal BMI at 2 wk (mean ± SD: 23.2 ± 3.0 kg/m(2)) and interacting maternal BMI with weight loss. In adjusted models, compared with daughters of women who did not lose weight, length and weight gain were lower in daughters whose mothers had a lower BMI at 2 wk postpartum coupled with the weight loss. For example, among mothers with an initial BMI of 18 kg/m(2), daughters of those who lost weight gained less weight [β = -0.29 kg (95% CI: -0.53, -0.06)] and length [β = -0.88 cm (95% CI: -1.52, -0.23)] from birth to 24 wk than daughters of those who gained weight. Though effects were only observed in girls, suggesting possible gender differences in suckling and feeding behavior, these findings indicate that maternal weight loss with low energy reserves represents a risk factor for poor infant growth outcomes.

Contraceptive availability during an emergency response in the United States.

This article provides the evidence for contraceptive need to prevent unintended pregnancy during an emergency response, discusses the most appropriate types of contraceptives for disaster situations, and details the current provisions in place to provide contraceptives during an emergency response.

The role of co-infections in mother-to-child transmission of HIV.

In HIV-infected women, co-infections that target the placenta, fetal membranes, genital tract, and breast tissue, as well as systemic maternal and infant infections, have been shown to increase the risk for mother-to-child transmission of HIV (MTCT). Active co-infection stimulates the release of cytokines and inflammatory agents that enhance HIV replication locally or systemically and increase tissue permeability, which weakens natural defenses to MTCT. Many maternal or infant co-infections can affect MTCT of HIV, and particular ones, such as genital tract infection with herpes simplex virus, or systemic infections such as hepatitis B, can have substantial epidemiologic impact on MTCT. Screening and treatment for co-infections that can make infants susceptible to MTCT in utero, peripartum, or postpartum can help reduce the incidence of HIV infection among infants and improve the health of mothers and infants worldwide.

Prevalence of hepatitis C virus infection among human immunodeficiency virus-1-infected pregnant women in Malawi: the BAN study.

In Sub-Saharan Africa, prevalence estimates of hepatitis C virus (HCV) vary widely.

Maternal and infant antiretroviral regimens to prevent postnatal HIV-1 transmission: 48-week follow-up of the BAN randomised controlled trial.

In resource-limited settings where no safe alternative to breastfeeding exists, WHO recommends that antiretroviral prophylaxis be given to either HIV-infected mothers or infants throughout breastfeeding. We assessed the effect of 28 weeks of maternal or infant antiretroviral prophylaxis on postnatal HIV infection at 48 weeks.

Pandemic 2009 influenza A (H1N1) in 71 critically ill pregnant women in California.

We sought to describe the characteristics and clinical management of 71 critically ill pregnant women with pandemic 2009 influenza A (H1N1 [2009 H1N1]). This was a retrospective case series from April 23, 2009, through March 18, 2010, of pregnant women with 2009 H1N1 in intensive care units in California. Among 71 critically ill pregnant women with 2009 H1N1, rapid decline in clinical status was noted with a median duration of 1 day from hospital admission to intensive care unit admission. Adverse events were common, and included sepsis (n = 26), hematologic disorder (n = 17), and pneumothorax (n = 15). Of 42 women requiring invasive ventilation, 15 (36%) died. In total, 23 women required rescue therapies for severe gas exchange abnormalities. Adverse events were significantly associated with survival (P = .0003). Women who received early antiviral treatment were significantly more likely to survive (relative risk, 1.43; 95% confidence interval, 1.18-1.75). Critically ill pregnant women with 2009 H1N1 declined rapidly and developed frequent adverse events including death.