This is a great question, and you're smart to think about how your medications may affect you and your prospective baby.
If you're currently taking hydrochlorothiazide and are actively trying to get pregnant, I recommend you contact your doctor right away to find out if he or she wants you to stay on it. The use of "thiazide" diuretics during the first trimester of pregnancy is not recommended, though only your doctor can determine if it is safe for you to continue with this medication or not. He or she knows your medical history and is in the best position to advise you on this.
So, my message is: Keep taking your hydrochlorothiazide unless you're told otherwise by your health care provider.
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