Pregnancy of uncertain viability : investigating a strategy for outcome prediction in Malta

Abstract

Purpose: Pregnancy of uncertain viability (PUV) is an intra-uterine pregnancy that does not present the ultrasonographic criteria to confirm viability or miscarriage. Follow-up scans are required until a definitive diagnosis is reached, resulting in patient anxiety and cost to the health services. The purpose of the study was to investigate PUV prediction and ultrasound followup strategies, in order to optimise PUV management. Objectives: The predictive aspect of the study analysed clinical, biochemical and ultrasonographic factors in relation to PUV outcome. Assessment included a bleeding score, ultrasound parameters and baseline Human Chorionic Gonadotropin (HCG) and Progesterone levels. The strategic aspect of the study compared interval ultrasound findings. Methodology: A prospective, non-experimental, quantitative, correlational design was adopted. Women diagnosed with PUV were followed up weekly until a definitive diagnosis of viability or miscarriage was made. The predictive parameters were analysed individually and in combination. The 7 and 14-day ultrasound findings were compared to identify an optimal follow-up strategy. Results: 43 women diagnosed with PUV, aged between 18 and 42 years were recruited, of whom 41.9% miscarried. Pregnancy loss was statistically associated with vaginal bleeding (p=0.003), presentation at a later gestational age (p=0.000) and with lower progesterone levels (p=0.000). Viable gestational sacs showed a faster daily MSD growth rate (1.161mm/day) than non-viable ones (0.769mm/day). A model combining bleeding, progesterone level and MSD was devised to predict PUV outcome. It had a sensitivity of 72.2% and a specificity of 88% (AUC=0.801). Ultrasound findings at 7 and at 14 days showed that 79% of the cohort received a definitive diagnosis by 7 days. Conclusions: A 7-day ultrasound follow-up strategy was seen to provide a definitive diagnosis in the majority of participants, suggesting that this strategy should be further investigated as it may play a role in the management of PUV patients in Malta.