A nurse is reviewing the health history of a client who has a new prescription for a combined oral contraceptive (COC). The nurse recognizes that which of the following client medications can interfere with the effectiveness of the COC?

GTPAL calculation:

Step 1 is: Determine Gravida (G) = 4 pregnancies (1 elective abortion, 1 twin birth, 1 spontaneous abortion, 1 current pregnancy) = G4.

Step 2 is: Determine Term (T) births = 0 (no pregnancies reached 37 weeks).

Step 3 is: Determine Preterm (P) births = 1 (twin birth at 36 weeks) = P1.

Step 4 is: Determine Abortion (A) = 2 (1 elective abortion at 9 weeks, 1 spontaneous abortion at 15 weeks) = A2.

Step 5 is: Determine Living (L) children = 2 (twins) = L2.

The GTPAL status is: G4 T0 P1 A2 L2.

Choice A rationale

A negative rubella titer indicates that the client does not have immunity to the rubella virus. Therefore, the statement that the client is immune to the rubella virus is incorrect.

Choice B rationale

While it is true that a person with a negative rubella titer needs a rubella vaccination, it is not recommended to administer the vaccine immediately during pregnancy due to the potential risks to the fetus. Therefore, this statement is not correct in this context.

Choice C rationale

The correct interpretation of a negative rubella titer in an antepartum client is that the client should receive a rubella immunization post-delivery. This is because rubella can cause serious complications if contracted during pregnancy, including congenital rubella syndrome in the newborn. Vaccination post-delivery will protect the client in future pregnancies.

Choice D rationale

A negative rubella titer does not provide information about whether the client is currently infected with the rubella virus. It only indicates that the client does not have immunity to the virus. Therefore, this statement is not a correct interpretation of the data.