What is the most likely diagnosis for a 22-year-old female with sudden abdominal bleeding and a syncopal episode during early pregnancy?

The diagnosis of a ruptured ectopic pregnancy is most likely in this scenario due to several critical factors. A 22-year-old female in early pregnancy experiencing sudden abdominal bleeding and a syncopal episode presents symptoms that are consistent with this condition.

Ruptured ectopic pregnancy occurs when a fertilized egg implants outside the uterus, most commonly in a fallopian tube. As the ectopic tissue grows, it can lead to significant internal bleeding, particularly if it ruptures. The syncopal episode indicates a possible loss of consciousness due to hypovolemia from blood loss, a situation that can arise in cases of severe hemorrhage.

In contrast, a miscarriage typically involves cramping and bleeding but is less likely to present with acute and severe symptoms such as syncope. Ovarian torsion can also cause abdominal pain and bleeding, but usually presents with unilateral pain rather than bleeding and is less commonly associated with syncopal episodes. Placenta previa would generally occur later in pregnancy and does not typically present with sudden onset of bleeding in early pregnancy, nor does it usually lead to syncopal episodes as the primary symptom.

Thus, the acute presentation combined with early pregnancy strongly suggests that a ruptured ectopic pregnancy is the most plausible diagnosis in this clinical scenario