The expectant management of women with early pregnancy of unknown location

Objective To assess the results of expectant management in women with pregn ancy of unknown location and to identify diagnostic parameters that are pre dictive of spontaneous pregnancy resolution. Design Prospective, observational study. Subjects Women with a positive pregnancy test and suspected early pregnancy complications who were referred for ultrasound assessment. Methods Women were first examined by transvaginal ultrasound to establish t he location and viability of pregnancy. All women with pregnancies that cou ld not be located on the scan had a blood sample taken to quantify the seru m human chorionic gonadotropin (hCG) and progesterone levels. Management wa s expectant until the pregnancy was identified, the condition resolved spon taneously or an intervention was required because clinical symptoms deterio rated or hCG levels did not decline. For each woman, age, clinical symptoms (pain and bleeding), menstrual dates, past gynecological history, endometr ial thickness and levels of serum hCC and progesterone were recorded. All p arameters were tested by univariate analysis and then analyzed in a stepwis e procedure to form a logistic regression model for predicting spontaneous resolution of pregnancy. Results A total of 1625 women were included in the study. In 135 cases (8%) the location of pregnancy was unknown. Complete data sets were obtained in 127 cases. These included 34 (27%) normal intrauterine pregnancies, 11 (9% ) miscarriages and 18 (14%) ectopic pregnancies. A total of 64 (50%) pregna ncies resolved spontaneously. Stepwise analysis showed that four diagnostic parameters - vaginal bleeding, endometrial thickness, serum hCG level and progesterone level - contributed significantly to the model, spontaneous pr egnancy resolution could be predicted at the initial visit with a sensitivi ty and specificity of 92%. Conclusions The majority of pregnancies of unknown location are abnormal; m any resolve spontaneously when managed expectantly. A logistic model may be used at the initial visit to identify those cases in which the pregnancy i s likely to resolve without the need for intervention.