Maternal age and risk of fetal death in singleton gestations: USA, 1995-2000.

OBJECTIVE: To determine the magnitude of risk for fetal death among singleton pregnancies in relation to maternal age, and to compare the risks with other common indications for fetal testing. STUDY DESIGN: We performed a retrospective cohort analysis of singleton births delivered between 1995 and 2000 using the US linked birth/infant death data. Gestational age at < 24 weeks and fetuses with anomalies were excluded. Fetal death rates at > or = 24 and > or = 32 weeks were calculated among women aged 15-19, 20-24, 25-29, 30-34, 35-39, 40-44 and 45-49 years, as well as for other common indications for testing: chronic and pregnancy-induced hypertension, diabetes and small-for-gestational age (SGA). The association between maternal age and fetal deaths was derived after adjusting for potential confounders through multivariable logistic regression models. Relative risks (RR) and 95% confidence intervals (CI) were derived from these models after adjusting for the effects of gravidity, race, marital status, prenatal care, education, smoking and placental abruption. RESULTS: Among the 21,610,873 singleton births delivered at > or = 24 weeks, fetal deaths occurred in 58,580 (2.7 per 1000). Births to young (15-19 years) and older (> or = 35 years) women comprised 12.6% and 11.4%, respectively. Compared with women aged 20-24 years, young women did not experience an increased risk of fetal death. However, increasing rates of fetal death at > or = 24 and at > or = 32 weeks were seen with increasing maternal age. The RR for fetal death at > or = 24 and at > or = 32 weeks among women 35-39 years were 1.21 and 1.31, respectively, while the RRs were 1.62 and 1.67 among women aged 40-44 years. Women 45-49 years were 2.40-fold (95% CI 1.77, 3.27) and 2.38-fold (95% CI 1.64, 3.46) as likely to deliver a stillborn fetus at > or = 24 weeks and > or = 32 weeks, respectively. RRs for fetal death at > or = 24 and > or = 32 weeks for hypertensive disease, diabetes, and SGA ranged between 1.46 and 4.95. CONCLUSION: Fetal deaths are increased among older women (> or = 35 years). Fetal testing in women of advanced maternal age may be beneficial.     

Prepregnancy obesity and fetal death: a study within the Danish National Birth Cohort

OBJECTIVE: To examine the association between high prepregnancy body mass index and fetal death, allowing for the effects of gestational age, weight gain, and maternal diseases in pregnancy. METHODS: Prepregnancy body mass index (BMI) and fetal death were examined in the Danish National Birth Cohort among 54,505 pregnant women who participated in a comprehensive interview during the second trimester. Pregnancy outcomes were obtained from registers and medical records. Cox regression analyses with delayed entry and time-dependent covariates were used to estimate the risk of fetal death. RESULTS: Compared with normal-weight women (18.5 < or = BMI < 25), the risks of fetal death among obese women (BMI > or = 30), expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were as follows: before week 14: 0.8 (0.5-1.4), weeks 14-19: 1.6 (1.0-2.5), weeks 20-27: 1.9 (1.1-3.3), weeks 28-36: 2.1 (1.0-4.4), weeks 37-39: 3.5 (1.9-6.4), and weeks 40+: 4.6 (1.6-13.4). Overweight women (25 < or = BMI < 30) also experienced a higher risk after 28 weeks, and especially after 40 weeks of gestation (HR 2.9, 95% CI 1.1-7.7). Analysis of stillbirth (fetal death at 28+ completed weeks of gestation) indicated that the effects were not due to obesity-related diseases in pregnancy, nor was weight gain associated with stillbirth. The increased risk of stillbirth among overweight and obese women was partly attributable to inadequate placental function (crude odds ratios 2.1, 95% CI 1.0-4.4, and 5.2, 95% CI 2.5-10.9, respectively). CONCLUSION: Prepregnancy obesity was associated with an increasing excess risk of fetal death with advancing gestation, and placental dysfunction may be a possible contributing factor.     

First Birth Cesarean and Risk of Antepartum Fetal Death in a Subsequent Pregnancy

Introduction: To examine the relationship between first birth by cesarean and antepartum fetal death in a subsequent pregnancy in a large, hospital‐based population. Methods : Data for this retrospective cohort study were taken from a database of all women who gave birth at Brigham and Women's Hospital during 4 waves of data collection beginning in 1994 and ending in 2002. We calculated the risk of antepartum fetal death in the subsequent pregnancy for women whose first birth was by cesarean compared to women with a vaginal first birth. Survival analysis was used to examine the influence of gestational age at birth. Results: Of 10,996 women who met inclusion criteria, 22% (n = 2450) had first births by cesarean, and 78% (n = 8546) had vaginal first births. The risk of antepartum fetal death in the subsequent pregnancy for women whose first birth was by cesarean was significantly greater than the risk for women whose first birth was vaginal (odds ratio 2.6; 95% confidence interval, 1.1‐6.2). The relationship between first birth cesarean and antepartum fetal death in a subsequent pregnancy differed by gestational age at birth, with no excess risk among women with a previous cesarean birth who gave birth before 34 weeks’ gestation but with a substantially increased risk for women who gave birth at 34 or more weeks’ gestation (unadjusted hazard ratio = 5.6; 95% confidence interval, 1.6‐19.8). Hazard ratio estimates for the association remained significant in bivariate models when adjusted for maternal height, weight, age, hypertension, and diabetes. Discussion: In these data, first birth by cesarean was associated with an increased risk of antepartum fetal death in a subsequent pregnancy. Our findings suggest that antepartum fetal deaths in subsequent pregnancies might be prevented by avoiding primary cesarean birth.     

High levels of fetal cell-free DNA in maternal serum: a risk factor for spontaneous preterm delivery

OBJECTIVE: This study was conducted to determine whether there is a relationship between the concentration of fetal cell-free DNA in maternal serum and the duration of pregnancy in women who are at high risk for preterm delivery because of either preterm labor or preterm premature rupture of the membranes. STUDY DESIGN: Sera were collected and frozen from 71 women with a male fetus. Maternal serum fetal cell-free DNA concentration was measured with the use of real-time polymerase chain reaction amplification of DYS1. Fetal cell-free DNA concentrations were converted to multiples of the median. The following groups were studied: group 1: women with preterm labor and intact membranes who were delivered at > or = 36 weeks of gestation (n = 21); group 2: women with preterm labor who were delivered at <36 weeks of gestation (n = 29); and group 3: women with preterm premature rupture of the membranes in labor (n = 20) or not in labor (n = 1) who were delivered prematurely (<36 weeks of gestation). Kaplan-Meier and Cox regression analyses were used to analyze the relationship between fetal cell-free DNA concentrations and the likelihood of preterm delivery. RESULTS: A cut-off value for fetal cell-free DNA of 1.82 multiples of the median was chosen for analysis. The cumulative rate of early preterm delivery (<30 weeks of gestation) was significantly higher for women with fetal cell-free DNA concentrations of > or = 1.82 multiples of the median than those with fetal cell-free DNA concentrations below this cut-off (45% [95% CI, 36%-74%] vs 18% [95% CI, 11%-25%]; P = .008]. The cumulative rate of preterm delivery (<36 weeks of gestation) was also significantly higher at > or = 1.82 multiples of the median (73% [95% CI, 52%-93%] vs 66% [95% CI, 54%-79%]; P = .02). After adjustment for covariates, Cox analysis showed that fetal cell-free DNA at > or = 1.82 multiples of the mechanisms of disease that are associated with a mean hazard rate of delivery of 1.57 (P = .005). CONCLUSION: High concentrations of fetal cell-free DNA in maternal serum are associated with an increased risk of spontaneous preterm delivery. This observation may have implications for the understanding of the mechanisms of disease that is associated with preterm labor.     

Adverse pregnancy outcome, the uteroplacental interface, and preventive strategies

Adverse pregnancy outcome (APO), includes fetal loss > or =20 weeks' gestation (fetal death), severe preeclampsia <36 weeks, or severe intrauterine growth restriction (severe IUGR) defined as birth weight < or =5th percentile or < or =10th percentile for gestational age. APO affects 8% of pregnant women (320,000 annually) and collectively contributes to the largest proportion of maternal/fetal mortality and morbidity. Women with prior APO in antecedent pregnancy are at high risk of an adverse maternal or fetal outcome in the subsequent pregnancy. Maternal serum markers and Doppler ultrasound can be used to predict adverse pregnancy outcome. There are no adequate, completed randomized trials for prophylactic measures; the roles of aspirin, calcium, and low molecular weight heparin need to be evaluated.     

Late pregnancy termination within a legislated medical environment

AIMS: To review the indications and outcomes for abortion beyond 20 weeks' gestation within an environment of legislated notifiable pregnancy termination. METHODS: In Western Australia legislation allowing abortion > or = 20 weeks' gestation for serious maternal-fetal conditions was enacted in May 1998. Late abortions are only permitted in a single state institution and are notifiable by law. All pregnancy terminations > or = 20 weeks' gestation performed since this legislation were prospectively identified with the indications and outcomes reviewed. RESULTS: During the study period, 219 women underwent abortion > or = 20 weeks' gestation, representing 0.5% of all abortions in the state. Comparison with 438 contemporanous medical abortions for fetal anomaly at 14-20 weeks' gestations was made. Misoprostol was the primary abortifacient for both. The median maternal age for termination at 14-20 weeks was 32 years (interquartile range (IQR) 27, 36) and 30 years (IQR 26, 34) at > or = 20 weeks' gestation (P < 0.001). There was no significant difference in maternal gravidity or parity. The principal indications for terminations > or = 20 weeks were: karyotypic (28.8%); cardiac anomalies (15.5%) and neural tube defects (11.9%). Cardiac anomalies represented 5.0% of fetal anomaly terminations at 14-20 weeks (P < 0.01). The median time for medical abortion was 15.4 h (IQR 11.5, 23.2) at 14-20 weeks' gestation compared with 18.3 h (IQR 13.3, 26.1) at gestations greater than 20 weeks (P < 0.001). A total of 13.2% of terminations were performed at gestations beyond 24 weeks. CONCLUSIONS: Abortion > or = 20 weeks' gestation under medically regulated legislation is used primarily for serious fetal anomalies. The women are younger and the abortion duration is greater for late pregnancy termination compared with those conducted at earlier gestations. The majority of late terminations occur < 23 weeks' gestation and the incidence has remained stable since the legislation was enacted.     

Epidemiology of fetal death in Latin America

BACKGROUND: To identify risk factors associated with fetal death, and to measure the rate and the risk of fetal death in a large cohort of Latin American women. METHODS: We analyzed 837,232 singleton births recorded in the Perinatal Information System Database of the Latin American Center for Perinatology and Human Development (CLAP) between 1985 and 1997. The risk factors analyzed included fetal factors and maternal sociodemographic, obstetric, and clinical characteristics. Adjusted relative risks were obtained, after adjustment for potential confounding factors, through multiple logistic regression models based on the method of generalized estimating equations. RESULTS: There were 14,713 fetal deaths (rate=17.6 per 1000 births). The fetal death risk increased exponentially as pregnancy advanced. Thirty-seven percent of all fetal deaths occurred at term, and 64% were antepartum. The main risk factors associated with fetal death were lack of antenatal care (adjusted relative risk [aRR]=4.26; 95% confidence interval, 3.84-4.71) and small for gestational age (aRR=3.26; 95% CI, 3.13-3.40). In addition, the risk of death during the intrapartum period was almost tenfold higher for fetuses in noncephalic presentations. Other risk factors associated with stillbirth were: third trimester bleeding, eclampsia, chronic hypertension, preeclampsia, syphilis, gestational diabetes mellitus, Rh isoimmunization, interpregnancy interval<6 months, parity > or =4, maternal age > or =35 years, illiteracy, premature rupture of membranes, body mass index > or =29.0, maternal anemia, previous abortion, and previous adverse perinatal outcomes. CONCLUSIONS: There are several preventable factors that should be dealt with in order to reduce the gap in fetal mortality between Latin America and developed countries.     

Socio-economic, demographic and obstetric risk factors for late fetal death of unknown etiology in Lithuania: a case--referent study

BACKGROUND: The purpose of this study was to evaluate the association between third trimester unexplained prelabor fetal deaths and various socio-economic, demographic and obstetric factors in Lithuania. METHODS: A case-referent study on 58 women with third trimester fetal death and 116 women with live fetus at term was carried out. Inclusion criteria for women in the first group (cases) were: prelabor fetal death of unknown etiology, singleton pregnancy >26 weeks of gestation and intact fetal membranes. For each case two referent women were recruited, admitted during the same period in active phase of labor at term (>37 weeks of gestation) with intact fetal membranes and fetus alive. Data were obtained by interview, anthropometry and by reviewing the medical records. Several potential socio-economic, demographic and obstetrical risk factors for unexplained fetal death were investigated. RESULTS: Univariate analyses determined several factors that were associated with fetal death of unknown etiology: low educational level, single marital status, low income, etc. After secondary logistic regression analysis only three independent variables remained significantly associated with otherwise unexplained stillbirth: small for gestational age fetus (OR 29.6; 95% CI 6.2-141.6), low income (OR 7.4; 95% CI 3.1-17.6), and maternal white blood cell count more than 16,000/mm3 (OR 5.4; 95% CI 1.4-21.6). Body mass index, smoking, occupation of women and other evaluated parameters were not confirmed to be significant risk factors. CONCLUSION: Small for gestational age fetus, low income and elevated maternal white blood cell count are factors significantly associated with late prelabor fetal death in Lithuania.     

Usefulness of quantitative polymerase chain reaction in amniotic fluid as early prognostic marker of fetal infection with Toxoplasma gondii

OBJECTIVE: Our purpose was to evaluate Toxoplasma gondii concentration in amniotic fluid (AF) samples as a prognostic marker of congenital toxoplasmosis. STUDY DESIGN: A retrospective study was carried out in 88 consecutive AF samples from 86 pregnant women, which were found positive by prospective polymerase chain reaction (PCR) testing. Parasite AF concentrations were estimated by real-time quantitative PCR and analyzed in relation to the clinical outcome of infected fetuses during pregnancy and at birth, taking into account the gestational age at maternal infection. RESULTS: A significant negative linear regression was observed between gestational age at maternal infection and T gondii DNA loads in AF. After adjusting for time at maternal seroconversion by multivariate analysis, higher parasite concentrations were significantly associated with a severe outcome of congenital infection (odds ratio [OR]=15.38/log (parasites/mL AF) [95% CI=2.45-97.7]). CONCLUSION: PCR quantification of T gondii in AF can be highly contributive for early prognosis of congenital toxoplasmosis. Maternal infections acquired before 20 weeks with a parasite load greater than 100/mL of AF have the highest risk of severe fetal outcome.     

The impact of prenatal care on neonatal deaths in the presence and absence of antenatal high-risk conditions

OBJECTIVE: The purpose of this study was to determine the association between prenatal care in the United States and the neonatal death rate in the presence and absence of antenatal high-risk conditions. STUDY DESIGN: Data were derived from the national perinatal mortality data sets for the years 1995 through 1997, which were provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred after 23 completed weeks of gestation. Multivariable logistic regression analyses were used to adjust for the presence or absence of various antenatal high-risk conditions, maternal age, gestational age at delivery, and birth weight. RESULTS: Of 10,530,608 singleton live births, 18,339 (1.7/1000 births) resulted in neonatal death. Neonatal death rates (per 1000 live births) were higher for African American infants compared with white infants in the presence (2.7 vs 1.5, respectively) and absence (10.7 vs 7.9, respectively) of prenatal care. Lack of prenatal care was associated with an increase in neonatal deaths, which was greater for infants born at > or =36 weeks of gestation (relative risk, 2.1; 95% CI, 1.8, 2.4). Lack of prenatal care was also associated with increased neonatal death rates in the presence of preterm premature rupture of the membranes (relative risk, 1.3; 95% CI, 1.1, 1.5), placenta previa (relative risk, 1.9; 95% CI, 1.2, 2.9), fetal growth restriction (relative risk, 1.7; 95% CI, 1.2, 1.6), and postterm pregnancy (relative risk, 1.4; 95% CI, 1.0, 2.9). CONCLUSION: In the United States, prenatal care is associated with fewer neonatal deaths in black and white infants. This beneficial effect was more pronounced for births that occurred at > or =36 weeks of gestation and in the presence of preterm premature rupture of the membranes, placenta previa, fetal growth restriction, and postterm pregnancy.     

Immediate and long term outcome of human parvovirus B19 infection in pregnancy

Objective To estimate more precisely the risk of fetal loss and congenital abnormalities after maternal parvovirus B19 infection, and to assess the long term outcome for surviving infants.
Design Prospective cohort study of pregnant women with confirmed B19 infection with follow up of the surviving infants. The rate of fetal loss in the study cohort was compared with that in pregnant women with varicella.
Setting Cases reported by laboratories in England and Wales between 1985-1988 and 1992–1995.
Sample Four hundred and twenty-seven pregnant women with B19 infection and 367 surviving infants of whom 129 were followed up at 7–10 years of age.
Methods Questionnaires to obstetricians and general practitioners on outcome of pregnancy and health of surviving infants. Maternal infection confirmed by B19-specific IgM assay and/or IgG seroconversion.
Results The excess rate of fetal loss in women with B19 infection was confined to the first 20 weeks of gestation and averaged 9%. Seven cases of fetal hydrops followed maternal infections between 9 and 20 weeks of gestation (observed risk 2.9%, 95% CI 1.2–5.9). No abnormalities attributable to B19 infection were found at birth in surviving infants (observed risk 0%, upper 95% CI 0.86%). No late effects were found at 7–10 years.
Conclusions Around 1 in 10 women infected before 20 weeks of gestation will suffer a fetal loss due to B19. The risk of an adverse outcome of pregnancy after this stage is remote. Infected women can be reassured that the maximum possible risk of a congenital abnormality due to B19 is under 1% and that long term development will be normal.     

The identification of risk of spontaneous fetal loss through second-trimester maternal serum screening

OBJECTIVE: The purpose of this study was to investigate associations between risk of spontaneous fetal loss and risk estimates for Down syndrome, trisomy 18, and neural tube defects assigned by second-trimester maternal serum screening. STUDY DESIGN: The study involved 264,653 women with available pregnancy outcomes who were screened between 15 and 20 weeks of gestation in the Ontario Maternal Serum Screening Program between October 1995 and September 2000. Pregnancies complicated by fetal chromosomal or structural abnormalities, insulin-dependent diabetes mellitus, and multiple pregnancies were excluded. Spontaneous fetal loss was defined as spontaneous miscarriage and intrauterine fetal demise as classified by the ICD-9 system, but including only those > or = 15 weeks of gestation. Women were grouped according to risk estimates for Down syndrome, trisomy 18, and neural tube defects, respectively. Spontaneous fetal loss rates by each risk group were evaluated after adjusting for losses associated with maternal age and amniocentesis. RESULTS: Fetal loss rates increased in women with risk estimates of > or = 1 in 1110 for trisomy 18 or neural tube defects, and > or = 1 in 130 for Down syndrome. The excessive fetal loss rates for these 3 groups of women were 14.4%, 3.2%, and 1.5% respectively. CONCLUSION: Fetal loss rate markedly increased in women with high-risk estimates for trisomy 18, neural tube defects, and Down syndrome. Risk estimates assigned by triple marker screening may provide an early means of stratifying pregnancies into risk for fetal loss.     

The effectiveness of antepartum surveillance in reducing the risk of stillbirth in patients with advanced maternal age

Objective

To estimate the effectiveness of antepartum surveillance and delivery at 41 weeks in reducing the risk of stillbirth in advanced maternal age (AMA) patients.

Study design

Retrospective cohort study of all patients managed in one maternal–fetal medicine practice from June 2005 to May 2012. We included all singleton pregnancies delivered at ≥20 weeks of gestation. All AMA patients (age ≥35 years at their estimated delivery date) underwent weekly biophysical profile testing beginning at 36 weeks, as well as planned delivery at 41 weeks, or sooner if indicated. We compared the rate of fetal death at ≥20 weeks and fetal death at ≥36 weeks in AMA vs. non-AMA patients. Fetal deaths due to lethal and chromosomal abnormalities were excluded.

Results

4469 patients met the inclusion criteria: 1541 (34.5%) were AMA and 2928 (65.5%) were non-AMA. Using our AMA protocol for surveillance and timing of delivery, the incidence of stillbirth was similar to the non-AMA population (stillbirth ≥20 weeks: 3.9 per 1000 vs. 3.4 per 1000, p = 0.799; stillbirth ≥36 weeks: 1.4 per 1000 vs. 1.1 per 1000, p = 0.773). When looking at women age <35, age 35–39, and age ≥40, the incidence of stillbirth ≥20 weeks and ≥36 weeks did not increase across the three groups. Our findings were similar when we excluded all patients with other indications for antepartum surveillance.

Conclusions

In AMA patients, antepartum surveillance and delivery at 41 weeks appears to reduce the risk of stillbirth to that of the non-AMA population. Routine antepartum surveillance should be considered in all AMA patients.     

Early onset severe pre-eclampsia: expectant management at a secondary hospital in close association with a tertiary institution

Objectives   Early onset severe pre-eclampsia is ideally managed in a tertiary setting. We investigated the possibility of safe management at secondary level, in close co-operation with the tertiary centre.
Design   Prospective case series over 39 months.
Setting   Secondary referral centre.
Population   All women ( n = 131) between 24 and 34 weeks of gestation with severe pre-eclampsia, where both mother and fetus were otherwise stable.
Methods   After admission, frequent intensive but non-invasive monitoring of mother and fetus was performed. Women were delivered on achieving 34 weeks, or if fetal distress or major maternal complications developed. Transfer to the tertiary centre was individualised.
Main outcome measures   Prolongation of gestation, maternal complications, perinatal outcome and number of tertiary referrals.
Results   Most women [ n = 116 (88.5%)] were managed entirely at the secondary hospital. Major maternal complications occurred in 44 (33.6%) cases with placental abruption (22.9%) the most common. One maternal death occurred and two women required intensive care admission. A mean of 11.6 days was gained before delivery with the mean delivery gestation being 31.8 weeks. The most frequent reason for delivery was fetal distress (55.2%). There were four intrauterine deaths. The perinatal mortality rate (≥1000 g) was 44.4/1000, and the early neonatal mortality rate (≥500 g) was 30.5/1000.
Conclusions   The maternal and perinatal outcomes are comparable to those achieved by other tertiary units. This model of expectant management of early onset, severe pre-eclampsia is encouraging but requires close co-operation between secondary and tertiary institutions. Referrals to the tertiary centre were optimised, reducing their workload and costs, and patients were managed closer to their communities.     

Early pre-eclampsia: what proportion of women qualify for expectant management and if not, why not?

OBJECTIVE: To determine what proportion of women with early pre-eclampsia qualify for expectant management and the magnitude of factors excluding this approach. STUDY DESIGN: A prospective case series with continuous data capture over one year at a tertiary referral centre. All women (n=169) with singleton pregnancies, presenting with early (> or =20 and <34 weeks' gestation) pre-eclampsia, were admitted, stabilised and evaluated. Major maternal or fetal complications at this stage were indications for delivery. However, when the pregnancy was otherwise stable, expectant management was commenced if the gestation was >or =24 weeks. Termination was offered from 20 to 23 weeks' gestation. RESULTS: Of the 169 women admitted, 82 (48.5%) were managed expectantly and 87 (51.5%) delivered after stabilisation and evaluation. Early fetal distress (32%) and major maternal complications (28%) were the most frequent reasons preventing expectant management. Ascites (18%) and HELLP syndrome (13%) ranked highest amongst the maternal complications. CONCLUSIONS: In this study, almost half of the women presenting with early onset pre-eclampsia qualified for expectant management. Early fetal distress was the most frequent reason preventing expectant management.     

The association between maternal factors and perinatal outcomes in triplet pregnancies

OBJECTIVE: The purpose of this study was to evaluate the associations between maternal factors and outcomes in triplet pregnancies. STUDY DESIGN: This was a historic cohort study of 194 triplet pregnancies of >or=24 weeks of gestation that were delivered from 1983 through 2001 from five medical centers. RESULTS: In analyses that were limited to pregnancies with all live-born triplets (178 pregnancies), women with a previous good outcome (>2500 g + >37 weeks of gestation) had longer gestations (+7.9 days, P =.03), better rates of fetal growth (+4.9 g/wk, P <.0001), and higher birth weights (+153 g, P <.0001). Maternal weight gains of <36 pounds by 24 weeks of gestation were associated with lower birth weights (-197 g, P <.0001), and fetal growth rates at 相似文献   

Fetal morbidity and mortality after acute human parvovirus B19 infection in pregnancy: prospective evaluation of 1018 cases

OBJECTIVE: To determine more precisely the incidence of fetal complications following maternal parvovirus B19 infection at various gestational ages. METHODS: An observational prospective study of 1018 pregnant women whose acute B19 infection was serologically confirmed in our laboratory. RESULTS: The observed rate of fetal death throughout pregnancy was 6.3% (64/1018) (95% confidence interval [CI]: 4.9, 8.0). The fetal death rate for those infected within the first 20 weeks of gestation (WG) was 64/579 (11.0%). Fetal death was only observed when maternal B19 infection occurred before the completed 20 WG. The observed stillbirth proportion was 0.6% (6/960). Three of six stillbirth cases presented with fetal hydrops. The overall risk of hydrops fetalis was 3.9% (40/1018) (95% CI: 2.8, 5.3). Three of 17 cases with non-severe hydrops and 13 of 23 cases with severe hydrops received intrauterine transfusion(s). The proportion of fetuses with severe hydrops that survived following fetal transfusions was 11/13 (84.6%). All of the non-transfused fetuses with severe hydrops died. CONCLUSION: Our data demonstrate a relevant B19-associated risk of fetal death, which is largely confined to maternal B19 infection in the first 20 WG. Timely intrauterine transfusion of fetuses with severe hydrops fetalis reduces the risk of fetal death. Parvovirus B19-associated stillbirth without hydropic presentation is not a common finding.     

The effect of malarial infection on maternal-fetal outcome in Ecuador.

OBJECTIVE: To describe maternal and fetal outcome among pregnancies complicated with malarial infection. METHODS: Charts of pregnancies complicated with malarial infection were reviewed. Parasital etiology and maternal/fetal data was analyzed. RESULTS: During the year 2001, at the Enrique C. Sotomayor Obstetrics and Gynecology Hospital, Guayaquil-Ecuador, 80 pregnancies complicated with malarial infection were admitted for treatment. This rendered an incidence of 2.1 per 1,000 live births (80/37,579). Mean maternal age was 25.2 +/- 6.7 years and the 19-29 age group was the most frequently affected (50%). On admittance, fever, chills, jaundice and anemia was present in 97.5%, 78.8%, 38.8% and 60% respectively. Falciparum was the most frequently presenting species (56.3%). Patients admitted at < 20 weeks gestation (n = 17) had a 76.5% and 82.4% abortion and adverse fetal outcome rate respectively. Among those admitted at 20-36 weeks (n = 55) the rates for preterm birth, intrauterine fetal death, low birthweight (LBW) and small-for-gestational age (SGA) were 34.5%, 11%, 40.8% and 48.9% respectively. Among patients admitted > 36 weeks, 87.5% (7/8) ended in a live term delivery. Adolescents presented a higher rate of anemia and SGA neonates. The overall (n = 80) abortion, preterm delivery and intrauterine fetal demise rates were 16.3%, 25% and 8.8% respectively. Chloroquine effectively treated 98.8% of cases and there was one maternal death due to falciparum infection. CONCLUSIONS: In this Ecuadorian population, malarial infection complicating gestation was associated to adverse maternal-fetal outcome, which was more evident among teenagers and pregnancies presenting malaria at an earlier gestational age.     

Determinants of unexplained antepartum fetal deaths

OBJECTIVE: To assess fetal, maternal, and pregnancy-related determinants of unexplained antepartum fetal death. METHODS: We conducted a hospital-based cohort study of 84,294 births weighing 500 g or more from 1961-1974 and 1978-1996. Unexplained fetal deaths were defined as fetal deaths occurring before labor without evidence of significant fetal, maternal, or placental pathology. RESULTS: One hundred ninety-six unexplained antepartum fetal deaths accounted for 27.2% of 721 total fetal deaths. Two thirds of the unexplained fetal deaths occurred after 35 weeks' gestation. The following factors were independently associated with unexplained fetal death: maternal prepregnancy weight greater than 68 kg (adjusted odds ratio [OR] 2.9; 95% confidence interval [CI] 1.85, 4.68), birth weight ratio (defined as ratio of birth weight to mean weight for gestational age) between 0.75 and 0.85 (OR 2.77; 95% CI 1.48, 5.18) or over 1.15 (OR 2.36; 95% CI 1.26, 4.44), fewer than four antenatal visits in women whose fetuses died at 37 weeks or later (OR 2.21; 95% CI 1.08, 4.52), primiparity (OR 1.74; 95% CI 1.26, 2.40), parity of three or more (OR 2.01; 95% CI 1.26, 3.20), low socioeconomic status (OR 1.59; 95% CI 1.14, 2.22), cord loops (OR 1.75; 95% CI 1.04, 2.97) and, for the 1978-1996 period only, maternal age 40 years or more (OR 3.69; 95% CI 1.28, 10.58). Trimester of first antenatal visit, low maternal weight, postdate pregnancy, fetal-to-placental weight ratio, fetal sex, previous fetal death, previous abortion, cigarette smoking, and alcohol use were not significantly associated with unexplained fetal death. CONCLUSION: In this study, we identified several factors associated with an increased risk of unexplained fetal death.     

An imbalance between angiogenic and anti-angiogenic factors precedes fetal death in a subset of patients: results of a longitudinal study

Objective.?Women with a fetal death at the time of diagnosis have higher maternal plasma concentrations of the anti-angiogenic factor, soluble vascular endothelial growth factor receptor (sVEGFR)-1, than women with a normal pregnancy. An important question is whether these changes are the cause or consequence of fetal death. To address this issue, we conducted a longitudinal study and measured the maternal plasma concentrations of selective angiogenic and anti-angiogenic factors before the diagnosis of a fetal death. The anti-angiogenic factors studied were sVEGFR-1 and soluble endoglin (sEng), and the angiogenic factor, placental growth factor (PlGF).

Methods.?This retrospective longitudinal nested case–control study included 143 singleton pregnancies in the following groups: (1) patients with uncomplicated pregnancies who delivered a term infant with an appropriate weight for gestational age (n?=?124); and (2) patients who had a fetal death (n?=?19). Blood samples were collected at each prenatal visit, scheduled at 4-week intervals from the first trimester until delivery. Plasma concentrations of sVEGFR-1, sEng, and PlGF were determined by specific and sensitive ELISA. A linear mixed-effects model was used for analysis.

Results.?(1) The average profiles of analyte concentrations as a function of gestational age for sVEGFR-1, sEng and PlGF were different between women destined to have a fetal death and those with a normal pregnancy after adjusting for covariates (p?<?0.05); (2) Plasma sVEGFR-1 concentrations in patients destined to have a fetal death were significantly lower between 7 and 11 weeks of gestation and became significantly higher than those of women with a normal pregnancy between 20 and 37 weeks of gestation (p?<?0.05); (3) Similarly, plasma sEng concentrations of women destined to have a fetal death were lower at 7 weeks of gestation (p?=?0.04) and became higher than those of controls between 20 and 40 weeks of gestation (p?<?0.05); (4) In contrast, plasma PlGF concentrations were higher among patients destined to develop a fetal death between 7 and 14 weeks of gestation and became significantly lower than those in the control group between 22 and 39 weeks of gestation (p?<?0.05); (5) The ratio of PlGF/(sVEGFR-1?×?sEng) was significantly higher in women destined to have a fetal death between 7 and 13 weeks of gestation (94–781%) and significantly lower (44–75%) than those in normal pregnant women between 20 and 40 weeks of gestation (p?<?0.05); (6) Similar results were obtained when patients with a fetal death were stratified into those who were diagnosed before or after 37 weeks of gestation.

Conclusions.?Fetal death is characterised by higher maternal plasma concentrations of PlGF during the first trimester compared to normal pregnancy. This profile changes into an anti-angiogenic one during the second and third trimesters.