Final answer:
The nurse should instruct the pregnant woman with PPROM to notify her obstetrician if she has a temperature above 37.8 C (100 F) to promptly address potential infections.
Step-by-step explanation:
A pregnant woman with preterm premature rupture of membranes (PPROM) at 34 weeks should be educated by the nurse on specific signs and practices to help manage her condition safely at home. The most accurate instruction for her would be to notify her obstetrician if she has a temperature above 37.8 C (100 F), as this could indicate an infection. Other important discharge instructions not mentioned explicitly in the options but crucial for her management include monitoring for labor signs, abstaining from intercourse, and avoiding placing anything into the vagina to prevent infection. Additionally, she should keep track of fetal movements, but an increase in fetal activity does not typically require reporting unless it is in the context of other concerning symptoms.