A 31-year-old woman, gravida 1 para 1, presents to the office because of heavy and painful
menstrual bleeding for the last 2 months. She reports soaking 12-15 sanitary pads during her last
menses. Her
menstrual cycle is regular, with 5-6 days of heavy bleeding. Menarche was at age 12. She is sexually active with one male partner and denies any
pain during intercourse. Past medical and surgical history is unremarkable. Temperature is 37° C (98.6°F),
pulse is 102/min, respirations are 19/min, and
blood pressure is 100/60 mmHg. Physical examination shows an enlarged
uterus with irregular contour. The remainder of the examination is unremarkable. Urine pregnancy test is negative. Complete blood count is as follows:
| Laboratory value | Result |
| Complete blood count |
| Hemoglobin (Hb) | 9 g/dL |
| Mean corpuscular volume (MCV) | 75 fL |
| Hematocrit | 32% |
| Leukocyte count | 9,100/mm3 |
| Platelet count | 400,000/mm3 |
| Neutrophils, segmented | 54% |
| Eosinophils | 1% |
| Basophils | 0% |
| Lymphocytes | 25% |
| Monocytes | 4% |
A transvaginal ultrasound is performed.
Reproduced from: radiopedia.org
Which of the following is the most likely origin of this patient’s ultrasound finding?
