In the case of PROM, blue dye can be seen on a stained tampon or pad after about 15–30 minutes. This method can be used to definitively make a diagnosis, but is rarely done because it is invasive and increases risk of infection. But, can be helpful if the diagnosis is still unclear after the above evaluations have been done.It is unclear if different methods of assessing the fetus in a woman with PPROM affects outcomes. False positives
Like amniotic fluid, blood, semen, vaginal secretions in the presence of infection, soap, urine, and cervical mucus also have an alkaline pH and can also turn nitrazine paper blue. Cervical mucus can also make a pattern similar to ferning on a microscope slide, but it is usually patchy and with less branching. Differential diagnosis
Other conditions that may present similarly to premature rupture of membranes are the following:
Urinary incontinence: leakage of small amounts of urine is common in the last part of pregnancy
Normal vaginal secretions of pregnancy
Increased sweat or moisture around the perineum
Increased cervical discharge: this can happen when there is a genital tract infection
Semen
Douching
Vesicovaginal fistula: an abnormal connection between the bladder and the vagina
Loss of the mucus plug

Prevention
Women who have had PROM are more likely to experience it in future pregnancies. There is not enough data to recommend a way to specifically prevent future PROM. However, any woman that has had a history of preterm delivery, because of PROM or not, is recommended to take progesterone supplementation to prevent recurrence.
Waiting usually requires a woman to stay in the hospital so that health care providers can watch her carefully for infection, placental abruption, umbilical cord compression, or any other fetal emergency that would require quick delivery by induction of labor.In 2017, a review of watchful waiting vs the early birth strategy was conducted to ascertain which was associated with a lower overall risk. Focusing on the 24–37-week range, the review analysed twelve randomised controlled trials from the "Cochrane Pregnancy and Childbirths Trials Register", concluding that "In women with PPROM before 37 weeks gestation with no contraindications to continuing the pregnancy, a policy of expectant management with careful monitoring was associated with better outcomes for the mother and baby. "There is believed to be a correlation between volume of amniotic fluid retained and neonatal outcomes before 26 weeks gestation. Amniotic fluid levels are an important consideration when debating expectant management vs clinical intervention, as low levels, or oligohydramnios, can result in lung and limb abnormalities. Additionally, labor and infection are less likely to occur when there are sufficient levels of amniotic fluid remaining in the uterus. Serial amnioinfusion in pregnancies with PPROM-related oligohydramnios at less than 26 weeks gestation, successfully alleviates oligohydramnios, with perinatal outcomes that are significantly better than the outcome in those with the persistent condition and is comparable with gestations with PPROM in which oligohydramnios never develops.