Differential Diagnosis for Spotting Blood during Pregnancy

Single most likely diagnosis

• Threatened abortion: This is the most common cause of spotting or bleeding in early pregnancy, especially at 5 weeks. The cramping and spotting can be symptoms of a threatened abortion, where the pregnancy is still viable but at risk.

Other Likely diagnoses

• Implantation bleeding: Although the patient is 5 weeks pregnant, it's possible that the bleeding is due to implantation of the embryo, which can occur around this time.
• Cervical polyp or cervical lesion: A cervical polyp or lesion can cause spotting or bleeding, especially if it's irritated or inflamed.
• Hormonal changes: Hormonal fluctuations during early pregnancy can cause spotting or light bleeding.

Do Not Miss (ddxs that may not be likely, but would be deadly if missed)

• Ectopic pregnancy: Although less likely, an ectopic pregnancy can cause spotting or bleeding, and it's a life-threatening condition that requires immediate attention.
• Molar pregnancy: A molar pregnancy can cause bleeding and cramping, and it's essential to rule out this condition to prevent complications.
• Placenta previa: Although rare at 5 weeks, placenta previa can cause bleeding and is a potentially life-threatening condition.

Rare diagnoses

• Septic abortion: Although rare, a septic abortion can cause bleeding, cramping, and other symptoms, and it's essential to consider this diagnosis, especially if the patient has a history of instrumentation or infection.
• Ovarian torsion: Ovarian torsion can cause severe pain and bleeding, although it's rare during pregnancy.
• Uterine rupture: Although extremely rare, uterine rupture can cause severe bleeding and is a life-threatening condition that requires immediate attention.