Utilization of obstetrical ultrasound in a referral population

Abstract

Objective. To determine the number of ultrasounds performed prior to presentation to a maternal-fetal medicine (MFM) sub-specialist and the patient's perceived reason for referral.

Study design. Women presenting for their first targeted ultrasound at an MFM unit in an urban center between November 2003 and April 2004 reported the number, location, and gestational age (GA) of prior ultrasounds and whether their insurance company had been billed for these studies. They also reported their current GA, insurance type, and perceived reason for referral. Pearson correlation and Kruskal–Wallis were used where appropriate; p < 0.05 was considered significant.

Results. Six hundred fifty-five women were invited to participate; 207 declined, leaving 448 available for the final analysis. The median number of prior ultrasounds was two (range 0–11). Twelve percent reported no prior ultrasound, 30% reported having had one, 28% reported having had two, and 29% reported having had three or more. Women presented at a mean GA of 21.3 ± 5.4 weeks. They reported having had their first ultrasound at 9.9 ± 2 weeks and their most recent prior ultrasound at 16.9 ± 6.7 weeks. GA at presentation did not correlate with the number of prior ultrasounds (r = 0.17). Of 396 women with at least one prior ultrasound, 336 had at least one performed in their doctor's office and 74 had at least one performed in an ultrasound clinic; 183 stated that their insurance had been billed and 168 did not know if their insurance had been billed. The majority, 60%, had private insurance, 37% had Medicaid, and 2% had no insurance. Women with private insurance had a higher number of prior ultrasounds than women with Medicaid (2.3 ± 1.4 vs. 1.5 ± 1.3, p < 0.001). In response to the perceived reason for referral, 280 women stated their reason for referral to the MFM unit was for a routine ultrasound or to determine gender, 158 women reported that they were referred because their doctor was concerned about ‘something’, and 10 were unsure of their indication.

Conclusion. Most women have at least one ultrasound prior to presenting to an MFM unit for a targeted scan. Many, especially those with private insurance, have had several prior ultrasounds. Patient education is needed about reasons for referral to an MFM unit for ultrasound and the possible increased financial burden of multiple ultrasounds.

Keywords:

• Targeted ultrasound
• referral population
• insurance
• maternal-fetal medicine