SonoStudy: Emergency Physicians can estimate gestational age in 1st trimester pregnancies

I recently posted about how emergency physicians can decrease the length of stay of patients with first trimester vaginal bleeding/pelvic pain (ruling out ectopic pregnancy) by performing a bedside pelvic ultrasound, which also had a couple cases to ponder about. As emergency physicians are getting more and more savvy with bedside ultrasound, it may benefit the patient’s future care if we are also able to tell them the gestational age. Well, this study (and great review) on emergency physicians-performed ultrasound estimating gestational age (compared with radiology results) highlights exactly that! And, guess what? we CAN estimate gestational age – shocking, I know. Below is the abstract:

ABSTRACT:

BACKGROUND: Patient reported menstrual history, physician clinical evaluation, and ultrasonography are used to determine gestational age in the pregnant female. Previous studies have shown that pregnancy dating by last menstrual period (LMP) and physical examination findings can be inaccurate. Radiology department ultrasound has proven to be the most accurate way of determining gestational age. The aim of this study is to determine the accuracy of emergency department ultrasound as an estimation of gestational age (EDUGA) in an emergency department (ED) population.

METHODS:

A prospective convenience sample of ED patients presenting in the first trimester of pregnancy (based upon self-reported LMP) regardless of their presenting complaint were enrolled. EDUGA was compared to gestational age estimated by ultrasound performed in the department of radiology (RGA) as the gold standard. Pearson’s product moment correlation coefficient was used to determine the correlation between EDUGA compared to RGA.

RESULTS:

Sixty-eight pregnant patients presumed to be in the 1st trimester of pregnancy based upon self-reported LMP consented to enrollment. When excluding the cases with no fetal pole, the median discrepancy of EDUGA versus RGA was 2 days (interquartile range (IQR) 1 to 3.25). The correlation coefficient of EDUGA with RGA was 0.978. When including the six cases without a fetal pole in the data analysis, the median discrepancy of EDUGA compared with RGA was 3 days (IQR 1 to 4). The correlation coefficient of EDUGA with RGA was 0.945.

CONCLUSION:

Based on our comparison of EDUGA to RGA in patients presenting to the ED in the first trimester of pregnancy, we conclude that emergency physicians are capable of accurately performing this measurement. Emergency physicians should consider using ultrasound to estimate gestational age as it may be useful for the future care of that pregnant patient.