Martingale is extreme and high risk trading strategy, because martingale trader will increase position size when first order dragged in floating loss, it is means in lower equity trader enforced to open bigger position size and this need higher margin requirement, increasing lot size will reduced margin level quickly and the dangerous thing is when the market against order hence will quickly faced margin call.
Trading martingale need bigger trading capital to survived account and understanding pipstep to open next position accordance to average movement in the timeframe.
Trading using MT4 FXOpen, I don't like to use martingale because too higher risk, for moderate risk taker, martingale is dangerous.