Can hormonal imbalance cause high blood pressure ? How can blood pressure be lowered naturally ?

Since you are prone to have high blood pressure, anything which further raises blood pressure is not safe for use. Mirena is a device placed within the uterus. It releases a hormone (progesterone) slowly and prevents ovulation, thus it is useful as a contraceptive. Now your blood pressure has risen because of the change from Lisinopril to Methyldopa, not because Mirena was removed. Progestogens can elevate BP if people are prone to HBP from before, so removing the Mirena should have controlled your BP. If you are planning for pregnancy, start taking Folic Acid and Calcium, meet your doctor in order to adjust the dose of methyldopa, modify your diet, exercise pattern, weight, sleep and stress levels. You need to be tested for secondary causes of hypertension and treatments will depend on the condition detected, if any. All the best.