Which of the following are used for the confirmation of rupture of membranes?

Rupture of membranes can be confirmed by using nitrazine paper to test residual fluid in the fornix or vaginal vault while performing a sterile speculum examination. Amniotic fluid has a pH of 7.0 to 7.4 and turns nitrazine paper a dark blue. Vaginal fluid typically has a pH of 4.5 to 5.5, and the nitrazine strip remains yellow. False positive results may occur in the presence of blood, lubricant, Trichomonas vaginalis, semen, or cervical mucus. Another test used to confirm rupture of membranes is ferning, which is the observation of sodium chloride crystals on a slide as amniotic fluid dries. It is also impoant to note the presence of meconium in amniotic fluid, indicated by the presence of thick, greenish brown fluid. Ref: VanRooyen M.J., Scott J.A. (2011). Chapter 105. Emergency Delivery. In R.K. Cydulka, G.D. Meckler (Eds), Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 7e.