Final answer:
The nursing diagnosis for a couple struggling with infertility after unsuccessful IVF is 'Impaired Family Processes', acknowledging their emotional strife and relationship strain.
Step-by-step explanation:
The nursing diagnosis that is most likely to apply to a couple who have been unable to conceive despite more than 2 years of trying and have just learned that in vitro fertilization (IVF) was unsuccessful, and are tearful, is d) Impaired Family Processes.
This diagnosis recognizes the emotional and psychological distress that can arise from challenges related to fertility. It encompasses the grief and potential strain on the couple's relationship due to their unfulfilled desire to have a child. Providing support and counseling can be essential for helping the couple cope with these difficulties.