Serum estradiol as an aid in the diagnosis of ectopic pregnancy.

The value of serum beta-hCG measurement in the diagnosis of ectopic pregnancy is well established, and there have been recent studies on the use of serum progesterone levels. However, we have been unable to find any reports on the potential application of serum estradiol (E2) assays in the diagnosis of ectopic pregnancy. We therefore concurrently measured serum E2, progesterone, and beta-hCG in 100 women with ectopic pregnancies, as well as in 69 controls with normal intrauterine pregnancies and 36 women with threatened abortion.