Nifedipine concentration in maternal and umbilical cord blood after nifedipine GITS tablets for tocolysis

Aims: Nifedipine is used “off-label“ for tocolysis. Since many years we use nifedipine GITS (gastro-intestinal therapeutic system) tablets. However, there is no safe information about the nifedipine concentrations in maternal and corresponding umbilical cord blood. Objective: To determine nifedipine concentration in maternal plasma at steady state and in maternal / umbilical cord plasma after tocolysis with nifedipine GITS tablets 30–150mg/d. Study design: Prospective study in pregnant women treated for threatening preterm labor, measuring nifedipine in maternal blood at steady state and in maternal (M) and corr…