Ectopic pregnancy with undetectable serum β-human chorionic gonadotropin

Ectopic Pregnancy (EP) has been estimated to complicate about 2% of pregnancies. The diagnosis of ectopic pregnancy is based on the demonstration of pregnancy using serum β-hCG assays in a patient into fertility age, associated with low abdominal pain and sometimes discrete vaginal bleeding of usually dark and scant blood. EP is characterized by low but detectable initial jβ-hCG level at 4 weeks of gestation or 9 days following a transfer of a blastocyst, and/or inappropriate rising in serum β-hCG levels, which one should duplicate in 48 hours to be considered normal evolution. Besides, is wise to take in account the fact of heterophils antibodies presence to avoid unjustified interventions, surgical or medical. Thus, a negative test confirmed with a urine negative test, usually allows the exclusion of the diagnosis of trophoblastic activity.   Weird cases of ectopic pregnancy with negative β-hCG assays have been reported previously[1-4]. We present an unusual case of ectopic pregnancy resulting in acute abdominal pain despite negative results for serum β-hCG tests.