Ultrasound guidance can be a safe and effective technique in obstetric and gynecologic procedures. Before beginning such a procedure, consider which approach will you take, transabdominal, transgluteal, or transvaginal. The approach that uses the shortest distance to the area of interest without transversing other structures is usually the best tolerated by the patient and will rarely result in complications, which are uncommon and usually minor, such as pain or self-limited bleeding. To select the shortest and safest path for access, review prior cross-sectional imaging and determine it on a case-by-case basis.

In cases of fluid management, such as benign adnexal cyst or peritoneal inclusion cyst fluid collection, note that you may need a larger needle gauge (18+) in those instances in which the fluid is thick. If you intend to test for malignancy, also take into account that fluid is generally less likely than solid tissue to give up the cells needed for a diagnosis.

Ultrasound guidance can also enable delivery of vascular acting medications directly where it is needed, as well as to guide direct gestation sac injection of potassium chloride (KCl) and/or methotrexate for cervical, interstitial, or C-section ectopic or heterotopic pregnancies in appropriate patients.

In conclusion, transvaginal or percutaneous ultrasound guidance can be used in the search for a diagnosis, in fluid collections, and to treat obstetric and gynecologic pathology, such as delivering medications to treat ectopic pregnancy or vascular conditions in select cases.

To learn more about this topic and see examples of its use, watch the full on-demand webinar, “Ultrasound-Guided Interventions to Treat Obstetric and Gynecologic Disease” presented by Tara A. Morgan, MD. Members of the American Institute of Ultrasound in Medicine can access it for free. Join today!

Read more from Tara A. Morgan, MD, on ultrasound guidance in the Journal of Ultrasound in Medicine:

• Cervical Lymph Node Features Predictive of Suboptimal Adequacy During Ultrasound-Guided Fine-Needle Aspiration in Thyroid Cancer Patients
• Distal Forearm Fracture Open Reduction–Internal Fixation: Sonographic Detection of Hardware Malalignment and Associated Tendon Injuries Missed by Radiography
• Transvaginal Ultrasound-Guided Fine-Needle Aspiration Biopsy of Pelvic Lesions
• Transvaginal Ultrasound-Guided Biopsy of Deep Pelvic Masses