Speciality
Spotlight

 




 

Obstetric
& Gynaecology


 

 




Medical Complications of Pregnancy

      

  • PJ Meis, RL Goldenberg, BM Mercer, et al, for the Maternal-Fetal Medicine Units Network of the National Institute of Child Health and Human Development (Natl Inst of Child Health and Human Development, Bethesda, Md) 78

    The Preterm Prediction Study: Risk Factors for Indicated Preterm Births.

    Am J Obstet Gynecol 178:562-567, 1998

        


    The term indicated preterm birth describes a medically indicated preterm delivery due to problems of the mother or fetus. Risk factors associated with indicated preterm birth were evaluated.

        


    2929 pregnant women were studied. 14.4% gave birth to their children at less than 37 weeks’ gestation.

        


    Authors concluded the risk factors identified for indicated preterm birth are generally different from those associated with spontaneous preterm birth. The only similar risk factors for both indicated and spontaneous preterm birth were lung disease, black ethnicity and working during pregnancy.

        


    In addition to the previous article, the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network has produced two more papers on the same subject.

        


    (1) JD Iams, (Ohio State Univ, Columbus)The Preterm Prediction Study: Recurrence Risk of Spontaneous Preterm Birth published in American Journal of Obstet Gynecol, 178:1035-1040, 1998 and (2) RL Goldenberg (Univ of Alabama, Birmingham; Ohio State Univ, Columbus; Univ of Tennesse, Memphis; et al) The Value of New vs Standard Risk Factors in Predicting Early and All Spontaneous Preterm Births published in Am Jr. Public Health, 88:233-238, 1998

        


    In this multicentric study of preterm prediction study, which was conducted between October 1992 and July 1994 and it was found that fibronectin was the most powerful single predictor in parous women but cervical length also contributed independently to estimation of recurrence risk. Women with a positive fibronectin status and a cervical length of less than 25mm had the highest risk of recurrence (64%) and the risk was lowest (7%) for those with a negative fibronectin status and a cervical length of more than 35mm.

       


    The strongest independent predictors of spontaneous preterm birth at less than 32 weeks’ gestation were the presence of fetal fibronectin (relative risk 14.1), a short cervix (£ 25 mm; relative risk 7.7), previous spontaneous preterm birth, vaginal bleeding, bacterial vaginosis and a body mass index of less than 19.8. 

        


    In non-black women, a body mass index less than 19 was more common and was always a stronger predictor of spontaneous preterm birth than in black women.

       


    Editorial comment on these 3 studies is that the Network should be congratulated for this excellent series of publications addressing an improtant breakthrough in the recognition of the risk factors of prematurity. The outstanding risk factors for a premature birth include a history of preterm birth, fetal fibronectin, bacterial vaginosis, short cervical length, and abnormal body mass index. There are remedies for bacterial vaginosis, which accounted for 40% of the attributable risk of spontaneous preterm birth at less than 32 weeks’. There is no doubt that many obstetricians need to learn that the predicted recurrence risk is increased by 2 to 4 fold in women with a positive-as compared with a negative fetal fibronectin. 

        


    However, according to the sage words of Goldenberg and Rouse, most interventions designed to prevent preterm birth do not work, and the few that do, including treatment of urinary tract infection, cerclage, and treatment of bacterial vaginosis in high risk women are not universally effective and are applicable to only a small percentage of women at risk for preterm birth. 

        


    In the meantime substantial reductions in preterm delivery are unlikely to be achieved. Prevention of prematurity is not imminent, but the seeds for success have been sown.

        

  • The Mode of Delivery and the Risk of Vertical Transmission of Human Immunodeficiency Virus Type1: A Meta-analysis of 15 prospective cohort studies. JS Read for the International Perinatal HIV Group (NIH, Bethesda, Md; et al), N. Engl J Med. 340:977-987, 1999.

        


    Although there may be a reduction in vertical transmission of HIV-1 with cesarean section, an association has not been demonstrated, perhaps because studies have been small. Results of meta-analysis using patient data from 15 prospective cohort studies are presented.

        


    Results: 15 studies and 8533 mother-child pairs were selected. Compared with other modes of delivery, delivery of cesarean section reduced vertical transmission by approximately 50%. Vertical transmission rates after membrane rupture after less than 1 hour or after more than 4 hours were similar. With retroviral therapy transmission rates were 10.4% for patients having cesarean section and 19% for patients not having cesarean section.

        


    Conclusion: Cesarean section appears to reduce vertical transmission rate of HIV-1 independent of retroviral therapy

        


    Editorial comment: Among those women who received prophylactic AZT, the risk of transmission with elective cesarean section was 10.4% vs 19.0% for vaginal birth. With AZT the transmission rate was 2% after abdominal birth vs 7.3% for vaginal birth. The only serious defect of this analysis is the failure clearly to express the severity of maternal diseases. This then is suggested here earlier is strong evidence for the desirability of managing HIV positive gravidas with prenatal and neonatal AZT as well as abdominal birth prior to rupture of the membranes or
    labour. The next few years should bring an update and effective prevention of newborn HIV by employing highly active retroviral treatment (HART) instead of AZT alone.

        

      



 

 

Speciality Spotlight

 

 

Medical Complications of Pregnancy
      

  • PJ Meis, RL Goldenberg, BM Mercer, et al, for the Maternal-Fetal Medicine Units Network of the National Institute of Child Health and Human Development (Natl Inst of Child Health and Human Development, Bethesda, Md) 78
    The Preterm Prediction Study: Risk Factors for Indicated Preterm Births.
    Am J Obstet Gynecol 178:562-567, 1998
        
    The term indicated preterm birth describes a medically indicated preterm delivery due to problems of the mother or fetus. Risk factors associated with indicated preterm birth were evaluated.
        
    2929 pregnant women were studied. 14.4% gave birth to their children at less than 37 weeks’ gestation.
        
    Authors concluded the risk factors identified for indicated preterm birth are generally different from those associated with spontaneous preterm birth. The only similar risk factors for both indicated and spontaneous preterm birth were lung disease, black ethnicity and working during pregnancy.
        
    In addition to the previous article, the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network has produced two more papers on the same subject.
        
    (1) JD Iams, (Ohio State Univ, Columbus)The Preterm Prediction Study: Recurrence Risk of Spontaneous Preterm Birth published in American Journal of Obstet Gynecol, 178:1035-1040, 1998 and (2) RL Goldenberg (Univ of Alabama, Birmingham; Ohio State Univ, Columbus; Univ of Tennesse, Memphis; et al) The Value of New vs Standard Risk Factors in Predicting Early and All Spontaneous Preterm Births published in Am Jr. Public Health, 88:233-238, 1998
        
    In this multicentric study of preterm prediction study, which was conducted between October 1992 and July 1994 and it was found that fibronectin was the most powerful single predictor in parous women but cervical length also contributed independently to estimation of recurrence risk. Women with a positive fibronectin status and a cervical length of less than 25mm had the highest risk of recurrence (64%) and the risk was lowest (7%) for those with a negative fibronectin status and a cervical length of more than 35mm.
       
    The strongest independent predictors of spontaneous preterm birth at less than 32 weeks’ gestation were the presence of fetal fibronectin (relative risk 14.1), a short cervix (£ 25 mm; relative risk 7.7), previous spontaneous preterm birth, vaginal bleeding, bacterial vaginosis and a body mass index of less than 19.8. 
        
    In non-black women, a body mass index less than 19 was more common and was always a stronger predictor of spontaneous preterm birth than in black women.
       
    Editorial comment on these 3 studies is that the Network should be congratulated for this excellent series of publications addressing an improtant breakthrough in the recognition of the risk factors of prematurity. The outstanding risk factors for a premature birth include a history of preterm birth, fetal fibronectin, bacterial vaginosis, short cervical length, and abnormal body mass index. There are remedies for bacterial vaginosis, which accounted for 40% of the attributable risk of spontaneous preterm birth at less than 32 weeks’. There is no doubt that many obstetricians need to learn that the predicted recurrence risk is increased by 2 to 4 fold in women with a positive-as compared with a negative fetal fibronectin. 
        
    However, according to the sage words of Goldenberg and Rouse, most interventions designed to prevent preterm birth do not work, and the few that do, including treatment of urinary tract infection, cerclage, and treatment of bacterial vaginosis in high risk women are not universally effective and are applicable to only a small percentage of women at risk for preterm birth. 
        
    In the meantime substantial reductions in preterm delivery are unlikely to be achieved. Prevention of prematurity is not imminent, but the seeds for success have been sown.
        

  • The Mode of Delivery and the Risk of Vertical Transmission of Human Immunodeficiency Virus Type1: A Meta-analysis of 15 prospective cohort studies. JS Read for the International Perinatal HIV Group (NIH, Bethesda, Md; et al), N. Engl J Med. 340:977-987, 1999.
        
    Although there may be a reduction in vertical transmission of HIV-1 with cesarean section, an association has not been demonstrated, perhaps because studies have been small. Results of meta-analysis using patient data from 15 prospective cohort studies are presented.
        
    Results: 15 studies and 8533 mother-child pairs were selected. Compared with other modes of delivery, delivery of cesarean section reduced vertical transmission by approximately 50%. Vertical transmission rates after membrane rupture after less than 1 hour or after more than 4 hours were similar. With retroviral therapy transmission rates were 10.4% for patients having cesarean section and 19% for patients not having cesarean section.
        
    Conclusion: Cesarean section appears to reduce vertical transmission rate of HIV-1 independent of retroviral therapy
        
    Editorial comment: Among those women who received prophylactic AZT, the risk of transmission with elective cesarean section was 10.4% vs 19.0% for vaginal birth. With AZT the transmission rate was 2% after abdominal birth vs 7.3% for vaginal birth. The only serious defect of this analysis is the failure clearly to express the severity of maternal diseases. This then is suggested here earlier is strong evidence for the desirability of managing HIV positive gravidas with prenatal and neonatal AZT as well as abdominal birth prior to rupture of the membranes or labour. The next few years should bring an update and effective prevention of newborn HIV by employing highly active retroviral treatment (HART) instead of AZT alone.
        

      

 

By |2022-07-20T16:41:31+00:00July 20, 2022|Uncategorized|Comments Off on Medical Complications of Pregnancy

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