Pregnancy in the emergency department: risk factors and prevalence among all women.

STUDY OBJECTIVE

To determine the prevalence of unrecognized pregnancy in the emergency department and to ascertain if patient history can effectively detect unrecognized pregnancies.

DESIGN

Prospective study.

SETTING

Urban ED with annual census of 40,000.

PARTICIPANTS

One hundred ninety-one consecutive women meeting inclusion criteria.

INTERVENTIONS

All participants completed a menstrual/sexual history questionnaire and had a urine pregnancy test.

RESULTS

Overall, we found a 6.3% prevalence of unrecognized pregnancy. Women with abdominal/pelvic complaints had a 13% prevalence; those with other complaints had a 2.5% prevalence. Two historical risk factors, the patient's suspicion that she might be pregnant and an abnormal last menstrual period, had a statistically significant correlation with unrecognized pregnancy. A third risk factor, the presence of abdominal/pelvic complaints, nearly achieved statistical significance. These risk factors detected all unrecognized pregnancies with a sensitivity of 100% and a specificity of 54%.

CONCLUSION

The prevalence of unrecognized pregnancy in our ED was 6.3%. Historical risk factors detected all of them.