Abstract: Caesarean scar Pregnancy (CSP) implanted in the caesarean section scar is a rare location among ectopic pregnancies that can be life-threatening. It can be classified at the same level of gravity as the placenta accreta. Hysterectomy is the gold standard treatment for massive bleeding. The diagnosis of pregnancy implanted in the caesarean section scar is a difficult diagnosis of the first trimester. It must be done as early as possible. Clinical manifestations are not specific, bleeding and pain is the most common symptoms. Endovaginal and pelvic ultrasound associated with Doppler is the first-line examination, provides optimal and panoramic vision, and studies reports of the gestational sac and its vasculature. Recent studies report the value of MRI in diagnosis because of its affinity for the study of pelvic tissue and the relationship of structures. The treatment remains non-consensual but it appears that the injection of methotrexate in situ by preferring the vaginal route is effective and not very morbid. We present here the case of a patient with CSP whose diagnosis was initially unknown.