High Versus Low Dose of Magnesium Sulfate as Initial Tocolytic Agent for Preterm Labour in Symptomatic Placenta Previa.
Condition: Placenta Previa Bleeding
MeSH terms: Obstetric Labor, Premature; Placenta Previa
Study type: Interventional
Phase: Phase 2

Summary: 
      To assess the efficacy and safety of alternative magnesium sulfate regimens when used as
      single agent tocolytic therapy for prevention of preterm labour in patients with symptomatic
      placenta previa and subsequent changes in the cervical length .
    

Detailed description: 
      Placenta previa is implantation of placenta on or near internal os .It is classified into
      major degree when lower edge of placenta lies within 2 cm from internal os , and minor degree
      if lower edge of placenta at lower uterine segment but more than 2 cm from internal os .

      There are many risk factors for developing placenta previa including multi parity , multiple
      pregnancy , increased maternal age (>35y ) , previous uterine surgery , history of placenta
      previa (4-8%) .

      A significant degree of uterine contractility has been observed with symptomatic placenta
      previa. It is directly associated with vaginal bleeding. However, a large percentage of women
      who have placenta previa associated with haemorrhage will experience subclinical uterine
      contractions before the onset of overt vaginal bleeding. Therefore, the use of tocolytic
      agents in management of placenta previa seems reasonable .

      Magnesium sulfate alters calcium up take, binding and distribution in smooth muscles of the
      uterus, so reduces the frequency of cell depolarization and inhibits myometrial contraction .

      In addition to its tocolytic action magnesium sulfate also provide neuroprotection to preterm
      infant . .

      At women Health Hospital, Assiut University, Egypt our policy is using magnesium sulfate as
      first line for tocolysis for placenta previa patients with preterm uterine contractions. By
      giving a loading dose of 4 g on 150 ml saline intravenous infusion over 20 minutes, and a
      maintenance dose of 6g/6h on 500 ml saline slow intra venous infusion
    

Intervention name(s): Magnesium sulfate
Intervention type(s): Drug
Intervention description(s): Patients will be assessed hourly for pulse and blood pressure, contraction frequency, vaginal bleeding. With strict monitoring for symptoms of magnesium sulfate toxicity.
All patients will receive dexamethasone to enhance fetal lung maturity. Rhesus factor status will be determined for all patients, . Hb level will be measured and anemic patients will receive correction by blood transfusion Cervical length will be measured after 24 h& 48 h from administration of magnesium sulfate in both groups Maternal serum magnesium will be measured at admission and after 4 hours ,12 hours and 24 hours after administration of magnesium sulfate Patients of both groups will be assessed for their neonatal outcomes include deaths and gestational age at delivery, fetal birth weight. Apgar score at five minutes, neonatal intensive care unit admission and duration of admission and neonatal calcium level at time of delivery will be also assessed.
Intervention MeSH terms: Magnesium Sulfate
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment