doctors believe I can't get pregnant because I had chemo

Hi,
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If your ovarian function is intact (after chemo and radiation), and if you had been having regular periods, it could suggest periodic and regular ovulation, or hormonal regulation due to use of birth control pills. If you have been regular in taking the pills at scheduled time daily, and have not missed any active pill intake, then you should have the protection. Bloating and nausea could be due to gastritis also. Look out for development of any new symptoms. Wait and watch for your periods/withdrawal bleeding and avoid further sexual contact until you have your periods. Chances of contraceptive failure are possible, and you might not experience all the symptoms suggestive of early pregnancy as the symptoms are manifested as your body’s response to hormonal changes (every women is different and few women do not experience any symptoms suggestive of pregnancy, while few women experience severe symptoms). If worried, visit your doctor/gynecologist for thorough examination, evaluation, clarification and assistance. Be in regular monitoring and follow-up with your treating doctor/gynecologist and report any new/abnormal symptoms immediately. Drink plenty of water. Take adequate rest. Maintain healthy diet and lifestyle.
Take care.