A nurse is caring for a patient who uses a contraceptive vaginal ring.

Which of the following symptoms should the nurse instruct the patient to report immediately?

The correct answer is choice B. Increased serum potassium level.Oral contraceptives can affect the levels of various electrolytes in the blood, such as sodium, potassium, calcium and magnesium.According to one study, oral contraceptives can increase the levels of serum copper, iron, calcium and cadmium, and decrease the levels of serum zinc, selenium, phosphorus and magnesium.

Therefore, a high serum potassium level can indicate an adverse effect of oral contraceptives on this client.

Choice A is wrong because oral contraceptives do not decrease serum glucose level.In fact, they can increase the plasma glucose level and insulin response, which can impair glucose tolerance and increase the risk of diabetes.

Choice C is wrong because oral contraceptives do not decrease serum triglyceride level.On the contrary, they can increase the fasting triglyceride level by 13 to 75 percent, which can elevate the risk of cardiovascular disease.

Choice D is wrong because oral contraceptives do not increase serum protein level.They can increase the levels of some apolipoproteins, such as A-I, A-II and B, but these are not the same as total protein.

The correct answer is choice C. The patient needs further teaching if they think that the implant can be inserted immediately after childbirth.According to Mayo Clinic, the implant should not be inserted until at least 21 days after giving birth, or until the milk supply is well established if breastfeeding.

Inserting the implant too soon may increase the risk of blood clots or decrease milk production.

Choice A is correct because condoms are still needed to protect against STIs, even if using the implant as a birth control method.Choice B is correct because irregular and unpredictable menstruation is a common side effect of the implant.Choice D is correct because the implant can prevent pregnancy for up to three years.