Abstract:
Objective: To study the association of change in serial beta HCG level over 48 hours and serum progesterone with
final diagnosis i.e. viable intrauterine pregnancy, ectopic pregnancy or failing pregnancy in cases initially labelled as
pregnancy of unknown location.
Study Design: prospective population based study
Place and duration of study: Early Pregnancy Assessment unit of Homerton University Hospital London from
December 2013 to February 2014
Methodology: Fifty patients were recruited in the study who presented to early pregnancy assessment unit and had
positive urine for pregnancy test but no evidence of pregnancy on transvaginal scan. Initial beta HCG, progesterone
and transvaginal scan were done in all cases. Patients were followed up with repeat HCG at 48 hour interval and
repeat TVS until final diagnosis was established.
Results: Final diagnosis was miscarriage 58%, viable intrauterine pregnancy 24% and ectopic pregnancy 12%. 67%
of patients with rise in HCG >60% had viable intrauterine pregnancy whereas all patients with >50% fall in HCG had
a miscarriage. A highly significant association of >60% rise of HCG with viable intrauterine pregnancy and of >50%
fall in HCG with miscarriage was observed with p-value<0.0001.
58% of patients with progesterone >30 had viable intrauterine pregnancy whereas 83% of patients with progesterone
<10 were miscarriage and 17% had ectopic pregnancy. A highly significant association of final diagnosis of viable
intrauterine pregnancy and progesterone level >30 was observed with p-value<0.0001.
Conclusion: Although there is high association of >60% rise in 48 hour repeat HCG and progesterone >30 with viable
intrauterine pregnancy, ectopic pregnancy cannot be ruled out on the basis of biochemical test. Therefore a high
index of suspicion is required to diagnose cases of ectopic pregnancy using clinical signs and symptoms, transvaginal
scan as well as biochemical tests such as serial beta HCG and progesterone levels
