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1.
N Engl J Med ; 388(13): 1161-1170, 2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-36757318

RESUMEN

BACKGROUND: The use of azithromycin reduces maternal infection in women during unplanned cesarean delivery, but its effect on those with planned vaginal delivery is unknown. Data are needed on whether an intrapartum oral dose of azithromycin would reduce maternal and offspring sepsis or death. METHODS: In this multicountry, placebo-controlled, randomized trial, we assigned women who were in labor at 28 weeks' gestation or more and who were planning a vaginal delivery to receive a single 2-g oral dose of azithromycin or placebo. The two primary outcomes were a composite of maternal sepsis or death and a composite of stillbirth or neonatal death or sepsis. During an interim analysis, the data and safety monitoring committee recommended stopping the trial for maternal benefit. RESULTS: A total of 29,278 women underwent randomization. The incidence of maternal sepsis or death was lower in the azithromycin group than in the placebo group (1.6% vs. 2.4%), with a relative risk of 0.67 (95% confidence interval [CI], 0.56 to 0.79; P<0.001), but the incidence of stillbirth or neonatal death or sepsis was similar (10.5% vs. 10.3%), with a relative risk of 1.02 (95% CI, 0.95 to 1.09; P = 0.56). The difference in the maternal primary outcome appeared to be driven mainly by the incidence of sepsis (1.5% in the azithromycin group and 2.3% in the placebo group), with a relative risk of 0.65 (95% CI, 0.55 to 0.77); the incidence of death from any cause was 0.1% in the two groups (relative risk, 1.23; 95% CI, 0.51 to 2.97). Neonatal sepsis occurred in 9.8% and 9.6% of the infants, respectively (relative risk, 1.03; 95% CI, 0.96 to 1.10). The incidence of stillbirth was 0.4% in the two groups (relative risk, 1.06; 95% CI, 0.74 to 1.53); neonatal death within 4 weeks after birth occurred in 1.5% in both groups (relative risk, 1.03; 95% CI, 0.86 to 1.24). Azithromycin was not associated with a higher incidence in adverse events. CONCLUSIONS: Among women planning a vaginal delivery, a single oral dose of azithromycin resulted in a significantly lower risk of maternal sepsis or death than placebo but had little effect on newborn sepsis or death. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; A-PLUS ClinicalTrials.gov number, NCT03871491.).


Asunto(s)
Antibacterianos , Azitromicina , Parto Obstétrico , Muerte Perinatal , Complicaciones Infecciosas del Embarazo , Sepsis , Femenino , Humanos , Recién Nacido , Embarazo , Azitromicina/administración & dosificación , Azitromicina/efectos adversos , Azitromicina/uso terapéutico , Muerte Perinatal/etiología , Muerte Perinatal/prevención & control , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/mortalidad , Complicaciones Infecciosas del Embarazo/prevención & control , Sepsis/epidemiología , Sepsis/mortalidad , Sepsis/prevención & control , Mortinato/epidemiología , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Parto Obstétrico/métodos , Sepsis Neonatal/epidemiología , Sepsis Neonatal/mortalidad , Sepsis Neonatal/prevención & control , Administración Oral , Resultado del Embarazo/epidemiología , Estados Unidos/epidemiología
2.
BJOG ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140197

RESUMEN

OBJECTIVE: To describe the intrapartum and postpartum use of non-study antibiotics in low- and middle-income countries (LMICs) during the double-blinded NICHD Global Network Azithromycin in Labor (A-PLUS) trial. DESIGN: The antibiotic use sub-study was a planned prospective, observational sub-study of the A-PLUS trial. SETTINGS: The study was carried out in hospitals or health centres affiliated with eight sites of the Global Network for Women's and Children's Health Research (Global Network) in seven countries: Bangladesh, Pakistan, India (two sites), Kenya, Zambia, The Democratic Republic of the Congo (DRC) and Guatemala. POPULATION: Totally, 29 278 pregnant women enrolled in the A-PLUS trial. METHODS: We collected data on 29 278 pregnant women admitted to a facility for delivery related to non-study antibiotic use overall and during three time periods: (1) in the facility prior to delivery, (2) after delivery until facility discharge and (3) after discharge to 42 days post-partum. MAIN OUTCOME MEASURES: Non-study antibiotic use overall and for treatment or prophylaxis by the site during the three time periods. RESULTS: Of the 29 278 women in the study, 5020 (17.1%; 95% CI 16.7%-17.6%) received non-study antibiotics in the facility prior to delivery, 11 956 (40.8%; 95% CI 40.3%-41.4%) received non-study antibiotics in the facility after delivery, and 13 390 (47.6%; 95% CI 47.0%-48.2%) women received non-study antibiotics after delivery and after facility discharge. Antibiotics were prescribed more often among women in the Asian and Guatemalan sites than in the African sites. In the three time-periods, among those receiving antibiotics, prophylaxis was the indication in 82.3%, 97.7% and 90.7% of the cases, respectively. The type of antibiotics used varied substantially by time-period and site, but generally, penicillin-type drugs, cephalosporin-type drugs and metronidazole were used more frequently than other types. CONCLUSIONS: Across the eight sites of the Global Network, in the facility before delivery, and in the post-partum periods before and after facility discharge, antibiotics were used frequently, but use was highly variable by site and time-period.

3.
BJOG ; 130 Suppl 3: 76-83, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37470087

RESUMEN

OBJECTIVE: To evaluate perinatal outcomes in preterm multiple compared with singleton pregnancies in India and Pakistan. DESIGN: Prospective, observational study. SETTINGS: Study hospitals in India and Pakistan. POPULATION: We evaluated 3897 preterm pregnancies. These mothers gave birth to 3615 (92.8%) singleton infants, 267 (6.8%) sets of twins, 14 (0.4%) sets of triplets and one set of quadruplets. MAIN OUTCOME MEASURES: Neonatal mortality, stillbirth, cause of death. RESULTS: Of the singleton infants, 691 (19.1%) were stillborn and 2924 (80.9%) live born. Of the 534 infants from twin pregnancies, 41 (7.7%) were stillborn and 493 (92.3%) were live born. Of the 267 sets of twins, in 14 cases (5.2%) both were stillborn, in 13 cases (4.8%) one was stillborn and one live born, and in 240 cases (90.0%) both were live born. In both preterm twins and preterm singletons, the three most common causes of death were intrauterine hypoxia, infections acquired prior to birth and infections acquired at or after birth. The preterm twins appeared less likely to have died from intrauterine hypoxia but more likely to have died from infections acquired at or after birth. Respiratory distress syndrome (RDS) was less likely considered by the panel to be the primary cause of death in either the twins (9.6%) or singletons (9.7%). Congenital anomalies were also not often judged to be the cause of death in either the preterm twins 2 (2.4%) or singletons 27 (5.3%). CONCLUSION: In the PURPOSe study, neonatal mortality rates in preterm twins compared with singletons when evaluated by sex, GA, birthweight and SGA, were generally similar to rates of preterm singleton neonatal mortality in those groups. Thus, the higher rate of mortality in live-born twin infants is related to the fact that these infants were more likely to be born earlier rather than to any inherent characteristics of the babies themselves.


Asunto(s)
Resultado del Embarazo , Nacimiento Prematuro , Femenino , Humanos , Recién Nacido , Embarazo , Hipoxia , Recién Nacido de Bajo Peso , Pakistán/epidemiología , Resultado del Embarazo/epidemiología , Embarazo Múltiple , Embarazo Gemelar , Nacimiento Prematuro/epidemiología , Estudios Prospectivos , Mortinato/epidemiología
4.
BJOG ; 130 Suppl 3: 140-148, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37470094

RESUMEN

OBJECTIVE: To determine the relation of COVID-19 symptoms to COVID-19 antibody positivity among unvaccinated pregnant women in low- and middle-income countries (LMIC). DESIGN: COVID-19 infection status measured by antibody positivity at delivery was compared with the symptoms of COVID-19 in the current pregnancy in a prospective, observational cohort study in seven LMICs. SETTING: The study was conducted among women in the Global Network for Women's and Children's Health's Maternal and Newborn Health Registry (MNHR), a prospective, population-based study in Kenya, Zambia, the Democratic Republic of the Congo (DRC), Bangladesh, Pakistan, India (Belagavi and Nagpur sites) and Guatemala. POPULATION: Pregnant women enrolled in the ongoing pregnancy registry at study sites. METHODS: Data on COVID-19 symptoms during the current pregnancy were collected by trained staff between October 2020 and June 2022. COVID-19 antibody testing was performed on samples collected at delivery. The relation between COVID-19 antibody positivity and symptoms was assessed using generalised linear models with a binomial distribution adjusting for site and symptoms. MAIN OUTCOME MEASURES: COVID-19 antibody status and symptoms of COVID-19 among pregnant women. RESULTS: Among 19 218 non-vaccinated pregnant women who were evaluated, 14.1% of antibody-positive women had one or more symptoms compared with 13.4% in antibody-negative women. Overall, 85.3% of antibody-positive women reported no COVID-19 symptoms during the present pregnancy. Reported fever was significantly associated with antibody status (relative risk [RR] 1.10, 95% CI 1.03-11.18; P = 0.008). A multiple variable model adjusting for site and all eight symptoms during pregnancy showed similar results (RR 1.13, 95% CI 1.04-1.23; P = 0.012). None of the other symptoms was significantly related to antibody positivity. CONCLUSIONS: In a population-based cohort in LMICs, unvaccinated pregnant women who were antibody-positive had slightly more symptoms during their pregnancy and a small but significantly greater increase in fever. However, for prevalence studies, evaluating COVID-19-related symptoms does not appear to be useful in differentiating pregnant women who have had a COVID-19 infection.


Asunto(s)
COVID-19 , Mujeres Embarazadas , Femenino , Humanos , Recién Nacido , Embarazo , Salud Infantil , COVID-19/diagnóstico , COVID-19/epidemiología , Prueba de COVID-19 , Países en Desarrollo , Estudios Prospectivos , Salud de la Mujer
5.
BJOG ; 130(4): 366-376, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36504437

RESUMEN

OBJECTIVES: To determine COVID-19 antibody positivity rates over time and relationships to pregnancy outcomes in low- and middle-income countries (LMICs). DESIGN: With COVID-19 antibody positivity at delivery as the exposure, we performed a prospective, observational cohort study in seven LMICs during the early COVID-19 pandemic. SETTING: The study was conducted among women in the Global Network for Women's and Children's Health's Maternal and Newborn Health Registry (MNHR), a prospective, population-based study in Kenya, Zambia, the Democratic Republic of the Congo (DRC), Bangladesh, Pakistan, India (two sites), and Guatemala. POPULATION: Pregnant women enrolled in an ongoing pregnancy registry at study sites. METHODS: From October 2020 to October 2021, standardised COVID-19 antibody testing was performed at delivery among women enrolled in MNHR. Trained staff masked to COVID-19 status obtained pregnancy outcomes, which were then compared with COVID-19 antibody results. MAIN OUTCOME MEASURES: Antibody status, stillbirth, neonatal mortality, maternal mortality and morbidity. RESULTS: At delivery, 26.0% of women were COVID-19 antibody positive. Positivity increased over the four time periods across all sites: 13.8%, 15.4%, 21.0% and 40.9%. In the final period, positivity rates were: DRC 27.0%, Kenya 33.1%, Pakistan 32.8%, Guatemala 37.0%, Zambia 37.8%, Bangladesh 47.2%, Nagpur, India 57.4% and Belagavi, India 62.4%. Adjusting for site and maternal characteristics, stillbirth, neonatal mortality, low birthweight and preterm birth were not significantly associated with COVID-19. The adjusted relative risk (aRR) for stillbirth was 1.27 (95% CI 0.95-1.69). Postpartum haemorrhage was associated with antibody positivity (aRR 1.44; 95% CI 1.01-2.07). CONCLUSIONS: In pregnant populations in LMICs, COVID-19 antibody positivity has increased. However, most adverse pregnancy outcomes were not significantly associated with antibody positivity.


Asunto(s)
COVID-19 , Nacimiento Prematuro , Niño , Embarazo , Femenino , Recién Nacido , Humanos , Resultado del Embarazo/epidemiología , Mortinato/epidemiología , Salud Infantil , Países en Desarrollo , Estudios Prospectivos , Prueba de COVID-19 , Pandemias , Nacimiento Prematuro/epidemiología , COVID-19/epidemiología , Salud de la Mujer , Mortalidad Infantil
6.
Clin Infect Dis ; 73(Suppl_5): S422-S429, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34910175

RESUMEN

BACKGROUND: Minimally invasive tissue sampling (MITS) is a noninvasive technique used to determine the cause of deaths. Very little is known about the factors that affect MITS acceptance or refusal. We present findings from a prospective study conducted in Southeast Asia on the reasons for accepting or refusing MITS. METHODS: This substudy was conducted in India and Pakistan to determine the acceptability of MITS in women who had a stillbirth or preterm live birth who later died. A formal questionnaire was used to gather observations during the consent for MITS, such as reasons for acceptance or refusal of MITS, as well as which family members were involved in the decision process. RESULTS: In Pakistan, the MITS acceptability forms were completed for 470 of 477 women (98.5%) with an eligible stillbirth for this substudy, and 334 of 337 (99.1%) with an eligible preterm neonatal death. In India, MITS acceptability forms were completed in 219 of 305 women (71.8%) with an eligible stillbirth and 260 of 264 (98.4%) with an eligible preterm neonatal death. In India, the most common reasons for MITS refusal for both stillbirths and preterm neonatal deaths were cultural concerns, while in Pakistan, the most common reason for MITS refusal was a potential delay in the funeral. The primary reason for accepting MITS was that the parents wanted to understand the cause of death. At both sites, fathers, mothers, and relatives, often in consultation, choose whether or not to accept MITS to determine the cause of death in stillbirths and preterm neonatal deaths. CONCLUSIONS: MITS was more commonly accepted in India than in Pakistan. Cultural concerns in India and funeral delays in Pakistan were common reasons for refusal. Parents from both sites were curious to know the cause of stillbirths and preterm neonatal deaths. The father, mother, and relatives were key decision makers for consenting to or declining MITS.


Asunto(s)
Muerte Perinatal , Mortinato , Autopsia/métodos , Causas de Muerte , Femenino , Humanos , Recién Nacido , Madres , Padres , Embarazo , Estudios Prospectivos , Mortinato/epidemiología
7.
Clin Infect Dis ; 73(Suppl_5): S368-S373, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34910185

RESUMEN

BACKGROUND: Review of data from multiple sources is often necessary to determine cause of death for stillbirths and neonatal deaths, especially in low- to middle-income countries (LMICs) where available data may vary. The minimally invasive tissue sampling (MITS) procedure provides granular histologic and microbiologic data that clinical reports and verbal autopsies cannot provide. Expert panel evaluation of data from individual deaths can be resource-intensive but remains essential to accurately infer causes of death. METHODS: The Project to Understand and Research Preterms and Stillbirths in South Asia (PURPOSe) study uses review panels to evaluate causes of death in 2 LMICs. To make the process manageable, a subset of the study variables was selected with professional input and organized into case reports. Case reports include clinical information, laboratory results, fetal or neonatal organ histology and polymerase chain reaction results from tissue obtained by MITS. Panelists evaluated the complete case report forms and then determined the cause of death based on available data. RESULTS: Computerized case reports averaged 2 to 3 pages. Approximately 6 to 8 cases were reviewed and discussed per 1-hour panel meeting. All panelists were provided the same information; missing data were noted. This limited bias between panelists and across meetings. Study teams notably took ownership of data quality. CONCLUSIONS: Standardized case reports for cause-of-death determination panel evaluation improve the efficiency of the review process, clarify available information, and limit bias across panelists, time, and location.


Asunto(s)
Muerte Perinatal , Mortinato , Autopsia/métodos , Causas de Muerte , Femenino , Humanos , Recién Nacido , Embarazo , Atención Prenatal , Mortinato/epidemiología
8.
Reprod Health ; 17(Suppl 2): 154, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256770

RESUMEN

BACKGROUND: While the relationship between hemoglobin (Hb) concentrations and pregnancy outcomes has been studied often, most reports have focused on a specific Hb cutoff used to define anemia. Fewer studies have evaluated pregnancy outcomes across the entire range of Hb values. Moreover, to date, most studies of the relationship of Hb concentrations to pregnancy outcomes have been done in high-income countries. Thus, we have sought to determine the relationship between the range of maternal Hb concentrations and adverse birth outcomes among South Asian pregnant women. METHODS: For this study, we used data collected from two South Asian countries (Pakistan - Sindh Province and two sites in India - Belagavi and Nagpur) in a prospective maternal and newborn health registry study. To assess the association between Hb concentrations and various maternal and fetal outcomes, we classified the Hb concentrations into seven categories. Regression analyses adjusting for multiple potential confounders were performed to assess adverse pregnancy outcomes across the range of Hb concentrations. FINDINGS: Between January 2012 and December 2018, 130,888 pregnant women were enrolled in the South Asian sites had a Hb measurement available, delivered and were included in the analyses. Overall, the mean Hb concentration of pregnant women from the sites was 9.9 g/dL, 10.0 g/dL in the Indian sites and 9.5 g/dL in the Pakistan site. Hb concentrations < 7 g/dL were observed in 6.9% of the pregnant Pakistani women and 0.2% of the Indian women. In both the Pakistani and Indian sites, women with higher parity and women with no formal education had lower Hb concentrations. In the Pakistani site, women > 35 years of age, women with ≥4 children and those who enrolled in the third trimester were more likely to have Hb concentrations of < 7 g/dL but these associations were not found for the Indian sites. When adjusting for potential confounders, for both India and Pakistan, lower Hb concentrations were associated with stillbirth, preterm birth, lower mean birthweight, and increased risk of low birthweight. In the Pakistani site, there was evidence of a U-shaped relationship between Hb concentrations and low birth weight, and neonatal mortality, and in India with hypertensive disease. INTERPRETATION: This study documented the relationship between maternal Hb concentrations and adverse pregnancy outcomes in women from the Pakistani and Indian sites across the range of Hb values. Both low and high Hb concentrations were associated with risk of at least some adverse outcomes. Hence, both low and high values of Hb should be considered risk factors for the mother and fetus.


Asunto(s)
Hemoglobinas/metabolismo , Salud del Lactante , Mortalidad Infantil , Complicaciones Hematológicas del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Mortinato/epidemiología , Adulto , Anemia/epidemiología , Niño , Femenino , Humanos , India/epidemiología , Lactante , Recién Nacido , Pakistán/epidemiología , Embarazo , Resultado del Embarazo/epidemiología , Mujeres Embarazadas , Nacimiento Prematuro/sangre , Nacimiento Prematuro/etiología , Estudios Prospectivos , Sistema de Registros
9.
Reprod Health ; 17(Suppl 2): 161, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256777

RESUMEN

BACKGROUND: Neonatal mortality causes a substantial proportion of the under-5 mortality in low and middle-income countries (LMIC). METHODS: We undertook a prospective, population-based research study of pregnant women residing in defined geographic areas in the Karnataka State of India, a research site of the Global Network for Women's and Children's Health Research. Study staff collected demographic and health care characteristics on eligible women enrolled with neonatal outcomes obtained at delivery and day 28. Cause of neonatal mortality at day 28 was assigned by algorithm using prospectively defined variables. RESULTS: From 2014 to 2018, the neonatal mortality rate was 24.5 per 1,000 live births. The cause of the 28-day neonatal deaths was attributed to prematurity (27.9%), birth asphyxia (25.1%), infection (23.7%) and congenital anomalies (18.4%). Four or more antenatal care (ANC) visits was associated with a lower risk of neonatal death compared to fewer ANC visits. In the adjusted model, compared to liveborn infants ≥ 2500 g, infants born weighing < 1000 g RR for mortality was 25.6 (95%CI 18.3, 36.0), for 1000-1499 g infants the RR was 19.8 (95% CI 14.2, 27.5) and for 1500-2499 g infants the RR was 3.1 (95% CI 2.7, 3.6). However, more than one-third (36.8%) of the deaths occurred among infants with a birthweight ≥ 2500 g. Infants born preterm (< 37 weeks) were also at higher risk for 28-day mortality (RR 7.9, 95% CI 6.9, 9.0) compared to infants ≥ 37 weeks. A one-week decrease in gestational age at delivery was associated with a higher risk of mortality with a RR of 1.3 (95% CI 1.3, 1.3). More than 70% of all the deliveries occurred at a hospital. Among infants who died, 50.3% of the infants had received bag/mask ventilation, 47.3% received antibiotics, and 55.6% received oxygen. CONCLUSIONS: Consistent with prior research, the study found that infants who were preterm and low-birth weight remained at highest risk for 28-day neonatal mortality in India. Although most of births now occur within health facilities, a substantial proportion are not receiving basic life-saving interventions. Further efforts to understand the impact of care on infant outcomes are needed. Study registration The trial is registered at clinicaltrials.gov. ClinicalTrial.gov Trial Registration: NCT01073475.


Asunto(s)
Muerte Perinatal , Nacimiento Prematuro/epidemiología , Población Rural , Adulto , Causas de Muerte , Niño , Femenino , Humanos , India/epidemiología , Lactante , Mortalidad Infantil , Recién Nacido de Bajo Peso , Recién Nacido , Embarazo , Complicaciones del Embarazo/epidemiología , Estudios Prospectivos
10.
Reprod Health ; 17(Suppl 3): 165, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33334352

RESUMEN

BACKGROUND: The objectives of this analysis were to document trends in and risk factors associated with the cesarean birth rate in low- and middle-income country sites participating in the Global Network for Women's and Children's Health Research (Global Network). METHODS: This is a secondary analysis of a prospective, population-based study of home and facility births conducted in the Global Network sites. RESULTS: Cesarean birth rates increased uniformly across all sites between 2010 and 2018. Across all sites in multivariable analyses, women younger than age twenty had a reduced risk of cesarean birth (RR 0.9 [0.9, 0.9]) and women over 35 had an increased risk of cesarean birth (RR 1.1 [1.1, 1.1]) compared to women aged 20 to 35. Compared to women with a parity of three or more, less parous women had an increased risk of cesarean (RR 1.2 or greater [1.2, 1.4]). Four or more antenatal visits (RR 1.2 [1.2, 1.3]), multiple pregnancy (RR 1.3 [1.3, 1.4]), abnormal progress in labor (RR 1.1 [1.0, 1.1]), antepartum hemorrhage (RR 2.3 [2.0, 2.7]), and hypertensive disease (RR 1.6 [1.5, 1.7]) were all associated with an increased risk of cesarean birth, p < 0.001. For multiparous women with a history of prior cesarean birth, rates of vaginal birth after cesarean were about 20% in the Latin American and Southeast Asian sites and about 84% at the sub-Saharan African sites. In the African sites, proportions of cesarean birth in the study were highest among women without a prior cesarean and a single, cephalic, term pregnancy. In the non-African sites, groups with the greatest proportion of cesarean births were nulliparous women with a single, cephalic, term pregnancy and all multiparous women with at least one previous uterine scar with a term, cephalic pregnancy. CONCLUSION: Cesarean birth rates continue to rise within the Global Network. The proportions of cesarean birth are higher among women with no history of cesarean birth in the African sites and among women with primary elective cesarean, primary cesarean after induction, and repeat cesarean in the non-African sites.


Asunto(s)
Tasa de Natalidad , Cesárea/estadística & datos numéricos , Cesárea/tendencias , Salud Infantil , Parto Vaginal Después de Cesárea/estadística & datos numéricos , Adulto , Cesárea/efectos adversos , Niño , Femenino , Humanos , Recién Nacido , Paridad , Vigilancia de la Población , Embarazo , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
11.
Reprod Health ; 17(Suppl 3): 176, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33334365

RESUMEN

BACKGROUND: Birth weight (BW) is a strong predictor of neonatal outcomes. The purpose of this study was to compare BWs between global regions (south Asia, sub-Saharan Africa, Central America) prospectively and to determine if trends exist in BW over time using the population-based maternal and newborn registry (MNHR) of the Global Network for Women'sand Children's Health Research (Global Network). METHODS: The MNHR is a prospective observational population-based registryof six research sites participating in the Global Network (2013-2018), within five low- and middle-income countries (Kenya, Zambia, India, Pakistan, and Guatemala) in threeglobal regions (sub-Saharan Af rica, south Asia, Central America). The birth weights were obtained for all infants born during the study period. This was done either by abstracting from the infants' health facility records or from direct measurement by the registry staff for infants born at home. After controlling for demographic characteristics, mixed-effect regression models were utilized to examine regional differences in birth weights over time. RESULTS: The overall BW meanswere higher for the African sites (Zambia and Kenya), 3186 g (SD 463 g) in 2013 and 3149 g (SD 449 g) in 2018, ascompared to Asian sites (Belagavi and Nagpur, India and Pakistan), 2717 g (SD450 g) in 2013 and 2713 g (SD 452 g) in 2018. The Central American site (Guatemala) had a mean BW intermediate between the African and south Asian sites, 2928 g (SD 452) in 2013, and 2874 g (SD 448) in 2018. The low birth weight (LBW) incidence was highest in the south Asian sites (India and Pakistan) and lowest in the African sites (Kenya and Zambia). The size of regional differences varied somewhat over time with slight decreases in the gap in birth weights between the African and Asian sites and slight increases in the gap between the African and Central American sites. CONCLUSIONS: Overall, BWmeans by global region did not change significantly over the 5-year study period. From 2013 to 2018, infants enrolled at the African sites demonstrated the highest BW means overall across the entire study period, particularly as compared to Asian sites. The incidence of LBW was highest in the Asian sites (India and Pakistan) compared to the African and Central American sites. Trial registration The study is registered at clinicaltrials.gov. ClinicalTrial.gov Trial Registration: NCT01073475.


Asunto(s)
Peso al Nacer , Países en Desarrollo , Mortalidad Infantil/tendencias , África , Asia , América Central , Niño , Estudios de Cohortes , Femenino , Salud Global , Humanos , Lactante , Mortalidad Infantil/etnología , Recién Nacido de Bajo Peso , Recién Nacido , Estudios Longitudinales , Masculino , Estudios Prospectivos
12.
Reprod Health ; 17(Suppl 2): 184, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256769

RESUMEN

BACKGROUND: The Global Network for Women's and Children's Health Research (Global Network) conducts clinical trials in resource-limited countries through partnerships among U.S. investigators, international investigators based in in low and middle-income countries (LMICs) and a central data coordinating center. The Global Network's objectives include evaluating low-cost, sustainable interventions to improve women's and children's health in LMICs. Accurate reporting of births, stillbirths, neonatal deaths, maternal mortality, and measures of obstetric and neonatal care is critical to determine strategies for improving pregnancy outcomes. In response to this need, the Global Network developed the Maternal Newborn Health Registry (MNHR), a prospective, population-based registry of pregnant women, fetuses and neonates receiving care in defined catchment areas at the Global Network sites. This publication describes the MNHR, including participating sites, data management and quality and changes over time. METHODS: Pregnant women who reside in or receive healthcare in select communities are enrolled in the MNHR of the Global Network. For each woman and her offspring, sociodemographic, health care, and the major outcomes through 42-days post-delivery are recorded. Study visits occur at enrollment during pregnancy, at delivery and at 42 days postpartum. RESULTS: From 2010 through 2018, the Global Network MNHR sites were located in Guatemala, Belagavi and Nagpur, India, Pakistan, Democratic Republic of Congo, Kenya, and Zambia. During this period at these sites, 579,140 pregnant women were consented and enrolled in the MNHR, nearly 99% of all eligible women. Delivery data were collected for 99% of enrolled women and 42-day follow-up data for 99% of those delivered. In this supplement, the trends over time and assessment of differences across geographic regions are analyzed in a series of 18 manuscripts utilizing the MNHR data. CONCLUSIONS: Improving maternal, fetal and newborn health in countries with poor outcomes requires an understanding of the characteristics of the population, quality of health care and outcomes. Because the worst pregnancy outcomes typically occur in countries with limited health registration systems and vital records, alternative registration systems may prove to be highly valuable in providing data. The MNHR, an international, multicenter, population-based registry, assesses pregnancy outcomes over time in support of efforts to develop improved perinatal healthcare in resource-limited areas. Trial Registration The Maternal Newborn Health Registry is registered at Clinicaltrials.gov (ID# NCT01073475). Registered February 23, 2019. https://clinicaltrials.gov/ct2/show/NCT01073475.


Asunto(s)
Salud del Lactante , Mortalidad Infantil , Mortalidad Materna , Mortalidad Perinatal , Resultado del Embarazo/epidemiología , Sistema de Registros/estadística & datos numéricos , Mortinato , Niño , Países en Desarrollo , Femenino , Guatemala , Humanos , Lactante , Recién Nacido , Pakistán , Embarazo , Estudios Prospectivos
13.
Reprod Health ; 17(Suppl 2): 146, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256783

RESUMEN

BACKGROUND: Stillbirth rates are high and represent a substantial proportion of the under-5 mortality in low and middle-income countries (LMIC). In LMIC, where nearly 98% of stillbirths worldwide occur, few population-based studies have documented cause of stillbirths or the trends in rate of stillbirth over time. METHODS: We undertook a prospective, population-based multi-country research study of all pregnant women in defined geographic areas across 7 sites in low-resource settings (Kenya, Zambia, Democratic Republic of Congo, India, Pakistan, and Guatemala). Staff collected demographic and health care characteristics with outcomes obtained at delivery. Cause of stillbirth was assigned by algorithm. RESULTS: From 2010 through 2018, 573,148 women were enrolled with delivery data obtained. Of the 552,547 births that reached 500 g or 20 weeks gestation, 15,604 were stillbirths; a rate of 28.2 stillbirths per 1000 births. The stillbirth rates were 19.3 in the Guatemala site, 23.8 in the African sites, and 33.3 in the Asian sites. Specifically, stillbirth rates were highest in the Pakistan site, which also documented a substantial decrease in stillbirth rates over the study period, from 56.0 per 1000 (95% CI 51.0, 61.0) in 2010 to 44.4 per 1000 (95% CI 39.1, 49.7) in 2018. The Nagpur, India site also documented a substantial decrease in stillbirths from 32.5 (95% CI 29.0, 36.1) to 16.9 (95% CI 13.9, 19.9) per 1000 in 2018; however, other sites had only small declines in stillbirth over the same period. Women who were less educated and older as well as those with less access to antenatal care and with vaginal assisted delivery were at increased risk of stillbirth. The major fetal causes of stillbirth were birth asphyxia (44.0% of stillbirths) and infectious causes (22.2%). The maternal conditions that were observed among those with stillbirth were obstructed or prolonged labor, antepartum hemorrhage and maternal infections. CONCLUSIONS: Over the study period, stillbirth rates have remained relatively high across all sites. With the exceptions of the Pakistan and Nagpur sites, Global Network sites did not observe substantial changes in their stillbirth rates. Women who were less educated and had less access to antenatal and obstetric care remained at the highest burden of stillbirth. STUDY REGISTRATION: Clinicaltrials.gov (ID# NCT01073475).


Asunto(s)
Parto Obstétrico , Países en Desarrollo , Complicaciones del Trabajo de Parto , Mortinato/epidemiología , Femenino , Guatemala/epidemiología , Humanos , India , Recién Nacido , Kenia , Masculino , Pakistán/epidemiología , Vigilancia de la Población , Embarazo , Estudios Prospectivos , Zambia/epidemiología
14.
Reprod Health ; 17(1): 19, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32000798

RESUMEN

BACKGROUND: Oligohydramnios is a condition of abnormally low amniotic fluid volume that has been associated with poor pregnancy outcomes. To date, the prevalence of this condition and its outcomes has not been well described in low and low-middle income countries (LMIC) where ultrasound use to diagnose this condition in pregnancy is limited. As part of a prospective trial of ultrasound at antenatal care in LMICs, we sought to evaluate the incidence of and the adverse maternal, fetal and neonatal outcomes associated with oligohydramnios. METHODS: We included data in this report from all pregnant women in community settings in Guatemala, Pakistan, Zambia and the Democratic Republic of Congo (DRC) who received a third trimester ultrasound as part of the First Look Study, a randomized trial to assess the value of ultrasound at antenatal care. Using these data, we conducted a planned secondary analysis to compare pregnancy outcomes of women with to those without oligohydramnios. Oligohydramnios was defined as measurement of an Amniotic Fluid Index less than 5 cm in at least one ultrasound in the third trimester. The outcomes assessed included maternal morbidity and fetal and neonatal mortality, preterm birth and low-birthweight. We used pairwise site comparisons with Tukey-Kramer adjustment and multivariable logistic models using general estimating equations to account for the correlation of outcomes within cluster. RESULTS: Of 12,940 women enrolled in the clusters in Guatemala, Pakistan, Zambia and the DRC in the First Look Study who had a third trimester ultrasound examination, 87 women were diagnosed with oligohydramnios, equivalent to 0.7% of those studied. Prevalence of detected oligohydramnios varied among study sites; from the lowest of 0.2% in Zambia and the DRC to the highest of 1.5% in Pakistan. Women diagnosed with oligohydramnios had higher rates of hemorrhage, fetal malposition, and cesarean delivery than women without oligohydramnios. We also found unfavorable fetal and neonatal outcomes associated with oligohydramnios including stillbirths (OR 5.16, 95%CI 2.07, 12.85), neonatal deaths < 28 days (OR 3.18, 95% CI 1.18, 8.57), low birth weight (OR 2.10, 95% CI 1.44, 3.07) and preterm births (OR 2.73, 95%CI 1.76, 4.23). The mean birth weight was 162 g less (95% CI -288.6, - 35.9) with oligohydramnios. CONCLUSIONS: Oligohydramnos was associated with worse neonatal, fetal and maternal outcomes in LMIC. Further research is needed to assess effective interventions to diagnose and ultimately to reduce poor outcomes in these settings. TRIAL REGISTRATION: NCT01990625.


Asunto(s)
Países en Desarrollo/estadística & datos numéricos , Feto/patología , Mortalidad Infantil/tendencias , Recién Nacido de Bajo Peso , Oligohidramnios/epidemiología , Resultado del Embarazo/epidemiología , Atención Prenatal/estadística & datos numéricos , Adulto , Femenino , Feto/diagnóstico por imagen , Guatemala/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Oligohidramnios/diagnóstico por imagen , Pakistán/epidemiología , Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal , Adulto Joven , Zambia/epidemiología
15.
Reprod Health ; 17(Suppl 3): 190, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33334329

RESUMEN

BACKGROUND: Pakistan has among the poorest pregnancy outcomes worldwide, significantly worse than many other low-resource countries. The reasons for these differences are not clear. In this study, we compared pregnancy outcomes in Pakistan to other low-resource countries and explored factors that might help explain these differences. METHODS: The Global Network (GN) Maternal Newborn Health Registry (MNHR) is a prospective, population-based observational study that includes all pregnant women and their pregnancy outcomes in defined geographic communities in six low-middle income countries (India, Pakistan, Democratic Republic of Congo, Guatemala, Kenya, Zambia). Study staff enroll women in early pregnancy and follow-up soon after delivery and at 42 days to ascertain delivery, neonatal, and maternal outcomes. We analyzed the maternal mortality ratios (MMR), neonatal mortality rates (NMR), stillbirth rates, and potential explanatory factors from 2010 to 2018 across the GN sites. RESULTS: From 2010 to 2018, there were 91,076 births in Pakistan and 456,276 births in the other GN sites combined. The MMR in Pakistan was 319 per 100,000 live births compared to an average of 124 in the other sites, while the Pakistan NMR was 49.4 per 1,000 live births compared to 20.4 in the other sites. The stillbirth rate in Pakistan was 53.5 per 1000 births compared to 23.2 for the other sites. Preterm birth and low birthweight rates were also substantially higher than the other sites combined. Within weight ranges, the Pakistani site generally had significantly higher rates of stillbirth and neonatal mortality than the other sites combined, with differences increasing as birthweights increased. By nearly every measure, medical care for pregnant women and their newborns in the Pakistan sites was worse than at the other sites combined. CONCLUSION: The Pakistani pregnancy outcomes are much worse than those in the other GN sites. Reasons for these poorer outcomes likely include that the Pakistani sites' reproductive-aged women are largely poorly educated, undernourished, anemic, and deliver a high percentage of preterm and low-birthweight babies in settings of often inadequate maternal and newborn care. By addressing the issues highlighted in this paper there appears to be substantial room for improvements in Pakistan's pregnancy outcomes.


Asunto(s)
Mortalidad Infantil/etnología , Mortalidad Materna/etnología , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Mortinato/etnología , Adulto , Países en Desarrollo , Femenino , Humanos , Lactante , Recién Nacido , Pakistán/epidemiología , Embarazo , Estudios Prospectivos , Mortinato/epidemiología
16.
Reprod Health ; 17(Suppl 2): 158, 2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33256782

RESUMEN

BACKGROUND: Babies born weighing ≥ 2500 g account for more than 80% of the births in most resource-limited locations and for nearly 50% of the 28-day neonatal deaths. In contrast, in high-resource settings, 28-day neonatal mortality among this group represents only a small fraction of the neonatal deaths. Yet mortality risks for birth weight of ≥ 2500 g is limited. Knowledge regarding the factors associated with mortality in these babies will help in identifying interventions that can reduce mortality. METHODS: The Global Network's Maternal Newborn Health Registry (MNHR) is a prospective, population-based observational study that includes all pregnant women and their pregnancy outcomes in defined geographic communities that has been conducted in research sites in six low-middle income countries (India, Pakistan, Democratic Republic of Congo, Guatemala, Kenya and Zambia). Study staff enroll all pregnant women as early as possible during pregnancy and conduct follow-up visits to ascertain delivery and 28-day neonatal outcomes. We analyzed the neonatal mortality rates (NMR) and risk factors for deaths by 28 days among all live-born babies with a birthweight ≥ 2500 g from 2010 to 2018 across the Global Network sites. RESULTS: Babies born in the Global Network sites from 2010 to 2018 with a birthweight ≥ 2500 g accounted for 84.8% of the births and 45.4% of the 28-day neonatal deaths. Among this group, the overall NMR was 13.1/1000 live births. The overall 28-day NMR for ongoing clusters was highest in Pakistan (29.7/1000 live births) and lowest in the Zambian/Kenyan sites (9.3/1000) for ≥ 2500 g infants. ≥ 2500 g NMRs declined for Zambia/Kenya and India. For Pakistan and Guatemala, the NMR remained almost unchanged over the period. The ≥ 2500 g risks related to maternal, delivery and newborn characteristics varied by site. Maternal factors that increased risk and were common for all sites included nulliparity, hypertensive disease, previous stillbirth, maternal death, obstructed labor, severe postpartum hemorrhage, and abnormal fetal presentation. Neonatal characteristics including resuscitation, hospitalization, congenital anomalies and male sex, as well as lower gestational ages and birthweights were also associated with increased mortality. CONCLUSIONS: Nearly half of neonatal deaths in the Global Network sites occurred in infants born weighing ≥ 2500 g. The NMR for those infants was 13.1 per 1000 live births, much higher than rates usually seen in high-income countries. The changes in NMR over time varied across the sites. Even among babies born ≥ 2500 g, lower gestational age and birthweight were largely associated with increased risk of mortality. Since many of these deaths should be preventable, attention to preventing mortality in these infants should have an important impact on overall NMR. TRIAL REGISTRATION: https://ClinicalTrials.gov Identifier: NCT01073475.


Asunto(s)
Países en Desarrollo , Mortalidad Infantil , Recién Nacido de Bajo Peso , Muerte Perinatal , Adulto , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Estudios Prospectivos
17.
Acta Obstet Gynecol Scand ; 98(3): 300-308, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30414270

RESUMEN

INTRODUCTION: Uncertainty exists regarding the impact of malpresentation on pregnancy outcomes and the optimal mode of delivery in low- and middle-income countries. We sought to compare outcomes between cephalic and non-cephalic pregnancies. MATERIAL AND METHODS: Using the NICHD Global Network's prospective, population-based registry of pregnancy outcomes from 2010 to 2016, we studied outcomes in 436 112 singleton pregnancies. Robust Poisson regressions were used to estimate the risk of adverse outcomes associated with malpresentation. We examined rates of cesarean delivery for malpresentation and compared outcomes between cesarean and vaginal delivery by region. RESULTS: Across all regions, stillbirth and neonatal mortality rates were higher among deliveries with malpresentation. In adjusted analysis, malpresentation was significantly associated with stillbirth (adjusted relative risk [aRR] 4.0, 95% confidence interval [CI] 3.7-4.5) and neonatal mortality (aRR 2.3, 95% CI 2.1-2.6). Women with deliveries complicated by malpresentation had higher rates of morbidity and mortality. Rates of cesarean delivery for malpresentation ranged from 27% to 87% among regions. Compared with cesarean delivery, vaginal delivery for malpresentation was associated with increased maternal risk, especially postpartum hemorrhage (aRR 5.0, 95% CI; 3.6-7.1). CONCLUSIONS: In a cohort of deliveries in low- and middle-income countries, malpresentation was associated with increased perinatal and maternal risk. Further research is needed to determine the best management of these pregnancies.


Asunto(s)
Parto Obstétrico/estadística & datos numéricos , Complicaciones del Trabajo de Parto/epidemiología , Resultado del Embarazo/epidemiología , Cesárea/estadística & datos numéricos , Países en Desarrollo , Femenino , Humanos , Renta/estadística & datos numéricos , Recién Nacido , Presentación en Trabajo de Parto , Embarazo , Factores Socioeconómicos , Nacimiento a Término
18.
Am J Perinatol ; 36(7): 730-736, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30372772

RESUMEN

OBJECTIVE: Few data are available on cesarean delivery and operative vaginal delivery trends in low- and middle-income countries. Our objective was to analyze a prospective population-based registry including eight sites in seven low- and middle-income countries to observe trends in operative vaginal delivery versus cesarean delivery rates over time, across sites. STUDY DESIGN: A prospective population-based study, including home and facility births among women enrolled from 2010 to 2016, was performed in communities in Argentina, Democratic Republic of Congo, Guatemala, India, Kenya, Pakistan, and Zambia. Women were enrolled during pregnancy and delivery outcome data were collected. RESULTS: We analyzed 354,287 women; 4,119 (1.2%) underwent an operative vaginal delivery and 45,032 (11.2%) delivered by cesarean. Across all sites with data for 7 years, rates of operative vaginal delivery decreased from 1.6 to 0.3%, while cesarean delivery increased from 6.4 to 14.4%. Similar trends were seen when individual country data were analyzed. Operative vaginal delivery rates decreased in both hospitals and clinics, except in the hospital setting at one of the Indian sites. CONCLUSION: In low- and middle-income countries, operative vaginal delivery is becoming less utilized while cesarean delivery is becoming an increasingly common mode of delivery.


Asunto(s)
Cesárea/tendencias , Parto Obstétrico/tendencias , África del Sur del Sahara , Asia Sudoriental , Parto Obstétrico/métodos , Países en Desarrollo , Femenino , Humanos , América Latina , Embarazo , Estudios Prospectivos
19.
Reprod Health ; 15(Suppl 1): 95, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29945645

RESUMEN

BACKGROUND: The prevalence of early pregnancy loss through miscarriage and medically terminated pregnancy (MTP) is largely unknown due to lack of early registration of pregnancies in most regions, and especially in low- and middle-income countries. Understanding the rates of early pregnancy loss as well as the characteristics of pregnant women who experience miscarriage or MTP can assist in better planning of reproductive health needs of women. METHODS: A prospective, population-based study was conducted in Belagavi District, south India. Using an active surveillance system of women of childbearing age, all women were enrolled as soon as possible during pregnancy. We evaluated rates and risk factors of miscarriage and MTP between 6 and 20 weeks gestation as well as rates of stillbirth and neonatal death. A hypothetical cohort of 1000 women pregnant at 6 weeks was created to demonstrate the impact of miscarriage and MTP on pregnancy outcome. RESULTS: A total of 30,166 women enrolled from 2014 to 2017 were included in this analysis. The rate of miscarriage per 1000 ongoing pregnancies between 6 and 8 weeks was 115.3, between 8 and 12 weeks the miscarriage rate was 101.9 per 1000 ongoing pregnancies and between 12 and 20 weeks the miscarriage rate was 60.3 per 1000 ongoing pregnancies. For those periods, the MTP rate was 40.2, 45.4, and 48.3 per 1000 ongoing pregnancies respectively. The stillbirth rate was 26/1000 and the neonatal mortality rate was 24/1000. The majority of miscarriages (96.6%) were unattended and occurred at home. The majority of MTPs occurred in a hospital and with a physician in attendance (69.6%), while 20.7% of MTPs occurred outside a health facility. Women who experienced a miscarriage were older and had a higher level of education but were less likely to be anemic than those with an ongoing pregnancy at 20 weeks. Women with MTP were older, had a higher level of education, higher parity, and higher BMI, compared to those with an ongoing pregnancy, but these results were not consistent across gestational age periods. CONCLUSIONS: Of women with an ongoing pregnancy at 6 weeks, about 60% will have a living infant at 28 days of age. Two thirds of the losses will be spontaneous miscarriages and one third will be secondary to a MTP. High maternal age and education were the risk factors associated with miscarriage and MTP. TRIAL REGISTRATION: The trial is registered at clinicaltrials.gov. ClinicalTrial.gov Trial Registration: NCT01073475 .


Asunto(s)
Aborto Inducido/estadística & datos numéricos , Aborto Espontáneo/epidemiología , Pobreza , Resultado del Embarazo/epidemiología , Femenino , Humanos , India/epidemiología , Lactante , Recién Nacido , Vigilancia de la Población , Embarazo , Estudios Prospectivos
20.
Reprod Health ; 15(Suppl 1): 89, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29945651

RESUMEN

BACKGROUND: In South Asia, where most stillbirths and neonatal deaths occur, much remains unknown about the causes of these deaths. About one-third of neonatal deaths are attributed to prematurity, yet the specific conditions which cause these deaths are often unclear as is the etiology of stillbirths. In low-resource settings, most women are not routinely tested for infections and autopsy is rare. METHODS: This prospective, cohort study will be conducted in hospitals in Davengere, India and Karachi, Pakistan. All women who deliver either a stillbirth or a preterm birth at one of the hospitals will be eligible for enrollment. With consent, the participant and, when applicable, her offspring, will be followed to 28-days post-delivery. A series of research tests will be conducted to determine infection and presence of other conditions which may contribute to the death. In addition, all routine clinical investigations will be documented. For both stillbirths and preterm neonates who die ≤ 28 days, with consent, a standard autopsy as well as minimally invasive tissue sampling will be conducted. Finally, an expert panel will review all available data for stillbirths and neonatal deaths to determine the primary and contributing causes of death using pre-specified guidance. CONCLUSION: This will be among the first studies to prospectively obtain detailed information on causes of stillbirth and preterm neonatal death in low-resource settings in Asia. Determining the primary causes of death will be important to inform strategies most likely to reduce the high mortality rates in South Asia. TRIAL REGISTRATION: Clinicaltrials.gov ( NCT03438110 ) Clinical Trial Registry of India ( CTRI/2018/03/012281 ).


Asunto(s)
Mortalidad Infantil , Recien Nacido Prematuro , Resultado del Embarazo , Mortinato , Adolescente , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Muerte Perinatal/etiología , Embarazo , Nacimiento Prematuro/mortalidad , Estudios Prospectivos
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