Final answer:
The most likely diagnosis is gestational hypertension.
Step-by-step explanation:
The most likely diagnosis in this patient is Gestational hypertension. Gestational hypertension is defined as new-onset hypertension without proteinuria after 20 weeks of gestation. In this case, the patient has an increase in blood pressure readings from her previous visits and no proteinuria. It is important to monitor her blood pressure closely and manage her condition to prevent complications.