Final answer:
The nurse should assess the client using high-dose estrogen oral contraceptives for increased blood pressure.
Step-by-step explanation:
The nurse would assess the client using high-dose estrogen oral contraceptives for increased blood pressure, as this can be a side effect of high-dose estrogen. Estrogen has an effect on blood vessels, causing them to constrict, which can lead to an increase in blood pressure. This is why it is important for the nurse to monitor the client's blood pressure regularly.
Weight gain and fluid retention are also possible side effects of high-dose estrogen oral contraceptives, but they are not the key finding the nurse would assess for in this case. Decreased blood pressure would not be an expected finding with high-dose estrogen.