Self-induced abortions are very dangerous and can lead to sterility, disease, hemoraghing, damage to organs, or death. Go to a paternity clinic to find out safer options.
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You cannot abort a baby without seeing a doctor. It is not only illegal but also extremely dangerous. Three months is already too late to just take medication.
Go to see someone NOW, you need...
No you can not. You are risking your life because your uterus could rupture. It is also illegal to attempt abortion by yourself without a doctors supervision.