A nurse is assisting with the care of a client on their first prenatal visit. Which of the following screenings require follow up intervention?

A. Negative varicella titer: A negative varicella titer indicates the client is susceptible to chickenpox. While vaccination is recommended postpartum, this finding does not require urgent intervention during pregnancy because live vaccines cannot be given while pregnant. B. Rubella titer nonimmune: A nonimmune rubella titer identifies susceptibility to rubella. Vaccination is provided postpartum, not during pregnancy, so immediate follow-up during the current pregnancy is not required. C. Positive Rh factor: A positive Rh factor indicates the client is Rh-positive, which poses no risk for hemolytic disease of the newborn. No immediate intervention is required; routine monitoring continues. D. Positive serologic test for syphilis: A positive syphilis test requires prompt follow-up because untreated maternal syphilis can cause miscarriage, stillbirth, or congenital infection. Early treatment with antibiotics during pregnancy is critical to prevent complications for both mother and fetus.