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L Mandelbrot

Publications and source records attributed to L Mandelbrot.

At least 55 records · Page 3Linked to original sources
PubMed1998

Vertical transmission of viral infections.

A variety of congenital viral infections are responsible for a large proportion of the mortality and morbidity in infancy and childhood. Vertical transmission may occur during primary maternal infection or during chronic or recurrent infection, with different implications for counselling and testing in pregnancy. Strategies for the diagnosis and prevention of mother-to-child transmission differ according to the timing and mechanisms involved. As demonstrated by hepatitis B research in the past and human immunodeficiency virus today, multicenter cohort studies and clinical trials are a key to developing effective interventions.

Cytomegalovirus Infections↗
PubMed1998

A randomised trial of mode of delivery in women infected with the human immunodeficiency virus.

OBJECTIVE: During the pilot phase of a trial to evaluate the effectiveness of caesarean section delivery compared with vaginal delivery in reducing mother-to-child transmission of human immunodeficiency virus (HIV) infection, the feasibility of randomisation to mode of delivery was assessed. DESIGN: At 36 weeks of pregnancy, women infected with HIV were randomly allocated to either caesarean section delivery at 38 weeks or vaginal delivery. Information was also collected on the reasons why women were not enrolled, either because they refused or had a contraindication. SETTING: Fifty-one centres in six European countries. POPULATION: Pregnant women with confirmed HIV-1 infection. MAIN OUTCOME MEASURES: Randomisation. RESULTS: Three-hundred and thirty-nine women had been randomised by the end of 1996, the large majority from Italy (n = 250) and France (n = 54), with 22 from South Africa, three from Sweden, nine from Barcelona and one from London. A further 150 women were eligible but had not been randomised. Forty-eight women (14%) were not delivered according to the arm to which they were randomised; the majority (n = 44) were changed from vaginal to caesarean section delivery. There is wide variation between European countries in the acceptability and adherence to the mode of delivery trial. CONCLUSION: The pilot phase of this trial has shown that in some settings randomisation to mode of delivery is feasible and acceptable, but that in other settings clinicians and pregnant women are more reluctant to be randomised. Pending further information on transmission rates and accrual, enrollment into the trial continues.

Cesarean Section↗
PubMed1998

HIV-1 infection and reproductive history: a retrospective study among pregnant women, Abidjan, Côte d'Ivoire, 1995-1996. Ditrame Project.

The aim of this paper is to determine the differences of fertility between HIV-1 infected and uninfected women in Abidjan, Côte d'Ivoire, using data available in an observational study conducted in 1995 and 1996 in 2 antenatal care centres in the district of Yopougon, Abidjan, within an intervention programme to reduce mother-to-child HIV-1 transmission (DITRAME project, ANRS 049). Fertility indicators have been constructed from retrospective data on pregnancies and births, and univariate and multivariate analyses have been performed on these indicators and stratified by age groups to compare HIV-1 positive and HIV-negative populations. The main outcome measures were the number of pregnancies, the number of miscarriages, the risk of miscarriage and the proportion of primigravida. Four thousand, three hundred and ninety-six women agreed to HIV testing: 12.1% were found to be HIV-1 infected. HIV-1 positive women had significantly fewer pregnancies than HIV-negatives in age-groups 25-29 (P = 0.05) and 30-34 (P = 0.008). The risk of having had at least one abortion or stillbirth was significantly higher for HIV-1 infected women than for HIV-negatives (OR = 1.28, 95% CI: 1.02-1.60), when controlling for social and demographic factors. This study suggests that HIV-1 infection has deleterious consequences on female fertility, with lower fertility rates and more frequent adverse pregnancy outcomes. Family planning and antenatal care services should consider antenatal HIV counselling and testing in women in areas of high HIV prevalence.

Adult↗
PubMed1997

Congenital adenomatoid malformation of the lung: when is active fetal therapy indicated?

OBJECTIVE: Although aggressive fetal therapies such as thoracoamniotic shunting can be applied to cystic adenomatoid malformations of the lung diagnosed in utero, there is no clear consensus regarding their indications. Our purpose was to evaluate a management policy in which aggressive fetal therapy was restricted to those cases complicated by major polyhydramnios or hydrops; all other cases were managed conservatively. STUDY DESIGN: A prospective cohort study of 33 cases with a prenatal diagnosis of cystic adenomatoid malformations of the lung was performed. Thoracoamniotic shunting was offered only in nine macrocystic cases with acute polyhydramnios or hydrops. RESULTS: Four cases were diagnosed postnatally as sequestrations. Of 12 cases complicated by acute polyhydramnios or hydrops, 5 survived (1 type III with spontaneous incomplete resolution in utero, 4 type I with substantial volume reduction after shunting). The 17 cases without acute polyhydramnios or hydrops were managed conservatively and survived. CONCLUSION: Conservative management is indicated in cases of cystic adenomatoid malformations of the lung without acute polyhydramnios or hydrops.

Cohort Studies↗
PubMed1997

Acceptability and impact of zidovudine for prevention of mother-to-child human immunodeficiency virus-1 transmission in France.

We studied the propagation and the impact of zidovudine prevention on the human immunodeficiency virus-1 transmission rate from infected mothers to their infants in the French nationwide prospective cohort. Infection was diagnosed in the children on the basis of at least two positive human immunodeficiency virus-1 polymerase chain reaction tests, culture, or both. The transmission rate among treated women was compared with that among untreated women during the same period and with that among women enrolled in the cohort since 1986. The impact of zidovudine was analyzed according to the women's clinical and biologic characteristics, the mode of delivery, and use of zidovudine therapy before the pregnancy. Nearly 90% of women were treated as soon as the second half of 1994. In 1994 and 1995, 80% of mother-child pairs received at least one of the three phases of preventive treatment. Among the 663 mothers enrolled during these 2 years, only six refused the treatment. Zidovudine treatment was associated with a reduction in the transmission rate of nearly two-thirds, from 14% +/- 6% to 5% +/- 2% (p < 0.01). The degree of reduction was not influenced by the maternal CD4+ cell count or p24 antigenemia at delivery. Zidovudine treatment of the mother before the pregnancy considerably reduced the impact of preventive therapy; the transmission rate was significantly higher among pretreated mothers (20% versus 5%, p < 0.01) even after adjusting for maternal CD4+ cell count. Zidovudine prevention is now widely used in France and has had a major impact on the epidemiology of mother-child human immunodeficiency virus transmission. This justifies a policy of offering human immunodeficiency virus screening to all women before or shortly after the diagnosis of pregnancy.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Maternal virus load during pregnancy and mother-to-child transmission of human immunodeficiency virus type 1: the French perinatal cohort studies. SEROGEST Cohort Group.

Virus load in pregnancy and its relation to mother-to-child human immunodeficiency virus (HIV) transmission were studied prospectively. From 1989 to 1994, 320 HIV-infected women from 18 centers had plasma samples stored. Among women not receiving antiretroviral therapy, the polymerase chain reaction RNA level was 3.6 log at delivery, and 15% of women had levels below the detection limit. There was no variation during pregnancy. Women born in sub-Saharan Africa had lower RNA levels, although their CD4 cell distribution did not differ from that in other women. Among 236 evaluable children, 19% +/- 5% were infected. Transmission occurred in 12% of cases (confidence interval, 5%-22%) with <1000 copies/mL versus 29% +/- 10% of those with >10,000 copies/mL (P < .02). Maternal virus load appears strongly related to HIV transmission to the child.

Africa South of the Sahara↗
PubMed1997

HIV-1 detection in cervicovaginal secretions during pregnancy.

OBJECTIVE: To assess the reproducibility of and factors associated with HIV detection in cervicovaginal secretions (CVS). DESIGN: Longitudinal study of 43 HIV-1-infected pregnant women in Paris. METHODS: HIV DNA was detected in peripheral blood mononuclear cells (PBMC) by Amplicor and gag nested polymerase chain reaction (PCR) assays. The HIV genotype was determined by heteroduplex mobility assay. Amplicor and gag nested PCR assays were performed on serial CVS samples for HIV DNA detection, and the HIV Monitor test was used for HIV RNA detection in plasma and CVS. RESULTS: A total of 144 CVS samples were collected from the women included in the study. HIV-1 DNA was detected in 36 (25%) of the 144 samples, from 16 (37.2%) of the 43 women. Results of HIV-1 DNA detection were concordant in the first two samples in 27 (84.4%) of the 32 women with at least two CVS samples. The last CVS sample collected in each woman was HIV-1 DNA-positive in 13 (30.2%) of the 43 women. Three factors were found to be independently associated with HIV-1 DNA detection in CVS: HIV-1 subtype B, absence of zidovudine therapy, and microbial cervicovaginal infection. HIV RNA was detected in CVS from 10 (23.3%) out of 43 women and correlated with DNA detection in the same sample and HIV RNA detection in plasma. CONCLUSIONS: DNA and RNA PCR can be used to detect HIV in cells and supernatants of CVS. These techniques may be useful in cohort studies to investigate HIV transmission and to evaluate the efficacy of antiretroviral drugs to reduce HIV excretion.

Adult↗
PubMed1996

Testing for in utero human immunodeficiency virus infection with fetal blood sampling.

OBJECTIVE: Our purpose was to evaluate the potential of midtrimester fetal blood sampling to detect in utero human immunodeficiency virus type 1 infection. STUDY DESIGN: Ultrasonographically guided fetal blood sampling was performed before pregnancy termination in 28 women infected with human immunodeficiency virus type 1. Mean gestational age was 22 weeks (range 15 to 29 weeks). Samples were tested for human immunodeficiency virus with undissociated p24 antigen and deoxyribonucleic acid polymerase chain reaction or viral isolation by cell culture. After terminations fetal thymuses were also tested for human immunodeficiency virus infection by polymerase chain reaction. Polymerase chain reaction was also performed on maternal cells to confirm that the primer pairs used were able to detect human immunodeficiency virus type 1 strains present. RESULTS: All fetal blood samples had negative results by p24 antigen and polymerase chain reaction or virus culture and all fetal thymuses were negative by polymerase chain reaction. CONCLUSION: Early in utero human immunodeficiency virus infection appears infrequent, supporting the hypothesis that mother-to-child transmission predominantly occurs late in pregnancy. Therefore midtrimester prenatal diagnosis is not currently of use to women in making reproductive decisions.

Antigens, Viral↗
PubMed1996

Congenital diaphragmatic hernia: can prenatal ultrasonography predict outcome?

OBJECTIVE: We wanted to establish whether prenatal ultrasonography predicts postnatal outcome in congenital diaphragmatic hernia. STUDY DESIGN: We designed a retrospective multicenter cohort study of 135 patients with congenital diaphragmatic hernia (122 left, 10 right, 2 bilateral, 1 anterior). In isolated left congenital diaphragmatic hernia five potential prenatal prognostic factors were studied: diagnosis at < or = 25 weeks' gestation, polyhydramnios, intrathoracic stomach, small abdomen, and major mediastinal shift. RESULTS: None of the 44 fetuses or infants who had multiple malformations survived. Of the 91 cases of isolated congenital diaphragmatic hernia, there were 82 live births; 76 of these infants had a left congenital diaphragmatic hernia. Of these, 51 (67%) died postnatally. A statistically significant relation was found between mortality and polyhydramnios, intrathoracic stomach, and major mediastinal shift. Mortality increased as a function of the number of these prognostic factors from 20% when none was present to 94% when all three were present. CONCLUSION: In the majority of cases of isolated left congenital diaphragmatic hernia the prognostic value of fetal ultrasonography is too low to alter perinatal management.

Cohort Studies↗
PubMed1996

Obstetric factors and mother-to-child transmission of human immunodeficiency virus type 1: the French perinatal cohorts. SEROGEST French Pediatric HIV Infection Study Group.

OBJECTIVE: We attempted to determine whether the risk of mother-to-child transmission of human immunodeficiency virus type 1 is related to events in pregnancy, labor, and delivery. STUDY DESIGN: In a prospective multicenter cohort study of human immunodeficiency virus type 1-infected mothers and their children, we studied pregnancy histories, labor (including gestational age, induction, membrane rupture, length of labor, intrapartum procedures, bleeding, infection, antiseptic technique, and antiretroviral therapy), and conditions of delivery. RESULTS: Among 1632 singleton infants, 310 were confirmed infected with human immunodeficiency virus type 1 at age 18 months (19.0% +/- 1.9%). Procedures (in particular, amniocentesis and amnioscopy) and sexually transmitted diseases during pregnancy, preterm delivery, premature membrane rupture, hemorrhage in labor, and bloody amniotic fluid were associated with increased transmission. Transmission was not related to mode of delivery or to the conditions of labor and delivery. CONCLUSIONS: Transmission was not decreased after emergency or elective cesarean section. Most risk factors either were rare or appeared poorly amenable to obstetric management, with the exception of invasive procedures, which should be avoided.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Acceptability of interventions to reduce mother-to-child transmission of HIV-1 in west Africa.

Would HIV-1-positive pregnant African women use interventions of AIDS testing, medication (oral or vaginal), and vaginal disinfection to reduce the likelihood of HIV-1 transmission to their child? In this pilot study in two west African cities (Abidjan, Côte d'Ivoire and Bobo-Dioulasso, Burkina Faso), social workers gave a native-language questionnaire to 607 pregnant women at four Maternal and Child Health Centers. The women were asked about their perception of the HIV test; consequences of testing and counseling; choice of medical intervention to protect the future child; and feelings about being in a randomized, placebo-controlled, clinical trial. Most accepted the principle of an AIDS test, said they wanted the agreement of their regular partner before being tested, and would use interventions to reduce the risk of vertical transmission. The researchers concluded that although concepts of informed consent, randomization, and placebo are difficult to understand, the study results are promising and encourage the evaluation of clinical trials to reduce mother-to-child transmission of HIV-1 in Africa.

AIDS Serodiagnosis↗
PubMed1995

Delivery of uncomplicated triplet pregnancies: is the vaginal route safer? A case-control study.

OBJECTIVE: Our purpose was to evaluate the safety of vaginal delivery of triplets. STUDY DESIGN: A retrospective case-control study on 69 consecutive triplet pregnancies delivered in the same institution between 1981 and 1992. Vaginal delivery was attempted in 23 otherwise uncomplicated triplet pregnancies, which form the study group. They were compared with 23 controls undergoing routine cesarean section and matched for gestational age at birth. Maternal hospital stay, neonatal mortality, hospitalization in the neonatal intensive care unit, and 5-minute Apgar scores were compared by means of paired t tests. RESULTS: In the vaginal delivery group there was one neonatal death related to prematurity (32 weeks) after intrapartum cesarean section for failure to progress. However, neonatal mortality was not significantly increased in comparison with controls (1 of 69 vs 0). In the study group Apgar scores were significantly higher (9.5 vs 8.4) and hospitalization in the neonatal care intensive unit was significantly shorter (6 vs 18 days) than in the cesarean section group (p < or = 0.002). CONCLUSION: In carefully selected cases vaginal delivery of triplets may be safe.

Adult↗
PubMed1995

Congenital chylothorax with hydrops: postnatal care and outcome following antenatal diagnosis.

We consecutively managed 25 cases of fetal chylothorax with hydrops (pleuroamniotic shunting in 20/25 cases). Three of the 16 liveborn infants died before day 5 from malformations (n = 1) or complications of antenatal origin (n = 2). Eleven of the 13 survivors were treated in our unit. Four infants whose chylothorax had resolved before birth following antenatal shunting were delivered at term, and had no respiratory disease. Seven infants, whose chylothorax persisted, were delivered prematurely and required intensive respiratory care (with mechanical ventilation for a median duration of 34 days). The 11 infants were maintained on total parenteral nutrition for a median duration of 31 days. They were discharged home after complete clinical recovery at a median age of 64 days. Antenatal pleuroamniotic shunting may improve the prognosis of congenital chylothorax with hydrops. Chylothorax persisting at birth resolves progressively with medical management.

Birth Weight↗