A transient rise of serum hCG levels which does not result in a recognizable pregnancy by ultrasound (i.e., hCG first level at 100, second level at 150, third level drops to 50).
A transient rise of serum hCG levels which does not result in a recognizable pregnancy by ultrasound (i.e., hCG first level at 100, second level at 150, third level drops to 50).