Elective caesarean-section versus vaginal delivery in prevention of vertical HIV-1 transmission: a randomised clinical trial

Background Results from observational studies suggest that caesarean-section delivery may reduce the risk of mother-to-child transmission of HIV-1 infection in comparison with vaginal delivery. We carried out a randomised clinical trial to address this issue and to assess the extent of postdelivery complications. Methods Eligible women were between 34 and 36 weeks of pregnancy, with a confirmed diagnosis of HIV-1 infection, and without an indication for caesarean-section delivery or a contraindication to this mode of delivery. Women were randomly assigned elective caesarean-section delivery at 38 weeks of pregnancy or vaginal delivery. An infant was classified as uninfected if he or she became negative for antibody to HIV-1 by age 18 months or was negative for virus by PCR or culture on at least two occasions, with no clinical, immunological, or viral evidence of infection. From 1993, to March, 1998, 436 women were randomised. Findings We present the results of an analysis updated to November, 1998, with data on the infection status of 370 infants. Three (1.8%) of 170 infants born to women assigned caesarean-section delivery were infected, compared with 21 (10.5%) of 200 born to women assigned vaginal delivery (p<0.001). Seven (3.4%) of 203 infants of women who actually gave birth by caesarean section were infected compared with 15 (10.2%) of 167 born vaginally (p=0.009). There were few postpartum complications and no serious adverse events in either group. Interpretation Our findings provide evidence that elective caesarean-section delivery significantly lowers the risk of mother-to-child transmission of HIV-1 infection without a significantly increased risk of complications for the mother

Elective Caesarean Section Versus Vaginal Delivery In Preventing Vertical Hiv-1 Transmission: A Randomized Clinical Trial.

Background Results from observational studies suggest that caesarean-section delivery may reduce the risk of mother-to-child transmission of HIV-1 infection in comparison with vaginal delivery. We carried out a randomised clinical trial to address this issue and to assess the extent of postdelivery complications. Methods Eligible women were between 34 and 36 weeks of pregnancy, with a confirmed diagnosis of HIV-1 infection, and without an indication for caesarean-section delivery or a contraindication to this mode of delivery. Women were randomly assigned elective caesarean-section delivery at 38 weeks of pregnancy or vaginal delivery. An infant was classified as uninfected if he or she became negative for antibody to HIV-1 by age 18 months or was negative for virus by PCR or culture on at least two occasions, with no clinical, immunological, or viral evidence of infection. From 1993, to March, 1998, 436 women were randomised. Findings We present the results of an analysis updated to November, 1998, with data on the infection status of 370 infants. Three (1.8%) of 170 infants born to women assigned caesarean-section delivery were infected, compared with 21 (10.5%) of 200 born to women assigned vaginal delivery (p<0.001). Seven (3.4%) of 203 infants of women who actually gave birth by caesarean section were infected compared with 15 (10.2%) of 167 born vaginally (p=0.009). There were few postpartum complications and no serious adverse events in either group. Interpretation Our findings provide evidence that elective caesarean-section delivery significantly lowers the risk of mother-to-child transmission of HIV-1 infection without a significantly increased risk of complications for the mother

Elective caesarean-section versus vaginal delivery in prevention of vertical HIV-1 transmission: a randomised clinical trial

Background. Results from observational studies suggest that caesarean-section delivery may reduce the risk of mother-to-child transmission of HIV-1 infection in comparison with vaginal delivery. We carried out a randomised clinical trial to address this issue and to assess the extent of postdelivery complications. Methods. Eligible women were between 34 and 36 weeks of pregnancy, with a confirmed diagnosis of HIV-1 infection, and without an indication for caesarean-section delivery or a contraindication to this mode of delivery. Women randomly assigned elective caesarean-section at 38 weeks of pregnancy or vaginal delivery. An infant was classified as uninfected if he or she became negative for antibody to HIV-1 by age 18 months or was negative for virus by PCR or culture on at least two occasions, with no clinical, immunological, or viral evidence of infection. From 1993, to March, 1998, 436 women were randomised. Findings. We present the results of an analysis updated to November, 1998, with data on the infection status of 370 infants. Three (1.8%) of 170 infants born to women assigned caesarean-section delivery were infected, compared with 21 (10.5%) of 200 born to women assigned vaginal delivery (p &lt; 0.001). Seven (3.4%) of 203 infants of women who actually gave birth by caesarean section were infected compared with 15 (10.2%) of 167 born vaginally (p = 0.009). There were few postpartum complications and no serious adverse events in either group. Interpretation. Our findings provide evidence that elective caesarean-section delivery significantly lowers the risk of mother-to-child transmission of HIV-1 infection without a significantly increased risk of complications for the mother

The mode of delivery and the risk of vertical transmission of human immunodeficiency virus type 1--a meta-analysis of 15 prospective cohort studies. The International Perinatal HIV Group.

To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19). Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine

Duration of ruptured membranes and vertical transmission of HIV-1: a meta-analysis from 15 prospective cohort studies

Objective: To test the a priori hypothesis that longer duration of ruptured membranes is associated with increased risk of vertical transmission of HIV. Design: The relationship between duration of ruptured membranes and vertical transmission of HIV was evaluated in an individual patient data meta-analysis. Methods: Eligible studies were prospective cohort studies including at least 100 mother-child pairs, from regions where HIV-infected women are counselled not to breastfeed. Analyses were restricted to vaginal deliveries and non-elective Cesarean sections; elective Cesarean section deliveries (those performed before onset of labour and before rupture of membranes) were excluded. Results: The primary analysis included 4721 deliveries with duration of ruptured membranes less than or equal to 24 h. After adjusting for other factors known to be associated with vertical transmission using logistic regression analysis to assess the strength of the relationship, the risk of vertical HIV transmission increased approximately 2% with an increase of 1 h in the duration of ruptured membranes [adjusted odds ratio, 1.02; 95% confidence interval, 1.01-1.04; for each 1 h increment]. There were no significant interactions of duration of ruptured membranes with study cohort or with any of the covariates, except maternal AIDS. Among women diagnosed with AIDS, the estimated probability of transmission increased from 8% to 31% with duration of ruptured membranes of 2 h and 24 h respectively (P < 0.01). Conclusions: These results support the importance of duration of ruptured membranes as a risk factor for vertical transmission of HIV and suggest that a diagnosis of AIDS in the mother at the time of delivery may potentiate the effect of duration of ruptured membranes. (C) 2001 Lippincott Williams & Wilkins

Duration of ruptured membranes and vertical transmission of HIV-1: A meta-analysis from 15 prospective cohort studies

Objective: To test the a priori hypothesis that longer duration of ruptured membranes is associated with increased risk of vertical transmission of HIV. Design: The relationship between duration of ruptured membranes and vertical transmission of HIV was evaluated in an individual patient data meta-analysis. Methods: Eligible studies were prospective cohort studies including at least 100 mother-child pairs, from regions where HIV-infected women are counselled not to breastfeed. Analyses were restricted to vaginal deliveries and non-elective Cesarean sections; elective Cesarean section deliveries (those performed before onset of labour and before rupture of membranes) were excluded. Results: The primary analysis included 4721 deliveries with duration of ruptured membranes ≤ 24 h. After adjusting for other factors known to be associated with vertical transmission using logistic regression analysis to assess the strength of the relationship, the risk of vertical HIV transmission increased approximately 2% with an increase of 1 h in the duration of ruptured membranes [adjusted odds ratio, 1.02; 95% confidence interval, 1.01-1.04; for each 1 h increment]. There were no significant interactions of duration of ruptured membranes with study cohort or with any of the covariates, except maternal AIDS. Among women diagnosed with AIDS, the estimated probability of transmission increased from 8% to 31% with duration of ruptured membranes of 2 h and 24 h respectively (P &lt; 0.01). Conclusions: These results support the importance of duration of ruptured membranes as a risk factor for vertical transmission of HIV and suggest that a diagnosis of AIDS in the mother at the time of delivery may potentiate the effect of duration of ruptured membranes. © 2001 Lippincott Williams &amp; Wilkins

The Mode Of Delivery And The Risk Of Vertical Transmission Of Human Immunodeficiency Virus Type 1. A Meta-Analysis Of 15 Prospective Cohort Studies

Background To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. Methods North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. Results The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19), Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. Conclusions The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine. (N Engl J Med 1999;340:977-87.) (C)1999, Massachusetts Medical Society

The mode of delivery and the risk of vertical transmission of human immunodeficiency virus type 1 - A meta-analysis of 15 prospective cohort studies

Background To evaluate the relation between elective cesarean section and vertical transmission of human immunodeficiency virus type 1 (HIV-1), we performed a meta-analysis using data on individual patients from 15 prospective cohort studies. Methods North American and European studies of at least 100 mother-child pairs were included in the meta-analysis. Uniform definitions of modes of delivery were used. Elective cesarean sections were defined as those performed before onset of labor and rupture of membranes. Multivariate logistic-regression analysis was used to adjust for other factors known to be associated with vertical transmission. Results The primary analysis included data on 8533 mother-child pairs. After adjustment for receipt of antiretroviral therapy, maternal stage of disease, and infant birth weight, the likelihood of vertical transmission of HIV-1 was decreased by approximately 50 percent with elective cesarean section, as compared with other modes of delivery (adjusted odds ratio, 0.43; 95 percent confidence interval, 0.33 to 0.56). The results were similar when the study population was limited to those with rupture of membranes shortly before delivery. The likelihood of transmission was reduced by approximately 87 percent with both elective cesarean section and receipt of antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, as compared with other modes of delivery and the absence of therapy (adjusted odds ratio, 0.13; 95 percent confidence interval, 0.09 to 0.19), Among mother-child pairs receiving antiretroviral therapy during the prenatal, intrapartum, and neonatal periods, rates of vertical transmission were 2.0 percent among the 196 mothers who underwent elective cesarean section and 7.3 percent among the 1255 mothers with other modes of delivery. Conclusions The results of this meta-analysis suggest that elective cesarean section reduces the risk of transmission of HIV-1 from mother to child independently of the effects of treatment with zidovudine. (N Engl J Med 1999;340:977-87.) (C)1999, Massachusetts Medical Society