Up until now the closest a woman has come to playing in the NHL is Manon Rheaume. Rheaume made history in 1992/93 when she played in exhibition games for the Tampa Bay Lightning. Despite never playing in an NHL regular season game, Rheaume would go onto play in the ECHL and IHL. Since that time another female has yet to make the NHL.
Now with the launch of the Professional Women's Hockey League it has become that much more likely that we finally see a female make an NHL debut. According to Ian Kennedy of The Hockey News, it's possible that a women finds herself making her NHL debut. With 6 PWHL teams it's possible that an Emergency Backup situation emerges that could force a team into a situation where they need a qualified backup.
This is certainly an intriguing idea, but this could get complicated due to the legality of contracts between the two leagues. Without question this could create an interesting situation, would teams be better served using a professional woman's goalie instead of a college goaltender or Zamboni driver?