Hallow Dear, With Implanon, you need not worry about pregnancy. Implanon contains a steroidal progestin named etonogestrel. Being progestational medicines, it may give symptoms of early pregnancy. It causes salt and water retention causing engorgement and tenderness of the breasts. Salt restriction may give you some relief. Also it increases the acidity in the stomach giving rise to nausea and vomiting. Some proton pump inhibitor antacid like Pantoprazole will give you some relief from these symptoms. If the symptoms remain intolerable even after a period of a month or so, you might have to switch over to some other contraceptive methods like condom or intrauterine device (without progesterone). Copper T might prove suitable for you. I hope this helps you. Dr. Nishikant Shrotri