The clinical outcome of pregnancies of unknown location: an audit of 112 cases

Pregnancy of unknown location (PUL) is a descriptive term applied when a woman presents with a positive pregnancy test but no signs of either intrauterine pregnancy (IUP) or ectopic pregnancy (EP) on ultrasound. This implies a level of diagnostic uncertainty requiring further investigation, with the main concern being an undetected EP. Method We examined the outcome of 112 pregnancies of unknown location (PUL) in a tertiary teaching hospital in New Zealand. Results Of 585 women referred to our service with a clinical suspicion of EP, 112 (19%) were categorised as PULs. The final outcomes in these women were complete miscarriage (52%), IUP (13%), presumed EP (11%), incomplete miscarriage (11%), confirmed EP (10%), and molar pregnancy (2%). A large proportion of women (42%) required a second ultrasound examination, and of those, 36% further required a third examination. The distribution of bHCG at presentation and symptomatology demonstrated considerable overlap in women with different clinical outcomes. Conclusion PUL continues to be a challenging and resource‐intensive clinical scenario. The rate of undiagnosed EP requiring intervention is around 10%, and the probability that a PUL represents a small nonvisualised ongoing IUP is relatively low (15%).