Ovarian cyst regression with levothyroxine in ovarian hyperstimulation syndrome associated with hypothyroidism.

Background: Spontaneous ovarian hyperstimulation syndrome (sOHSS) can occur following hypothyroidism. Ultrasonography facilitates diagnosis and monitoring of this syndrome. We describe ovarian sonographic changes in a hypothyroid patient with sOHSS after treatment with levothyroxine (l-T4).

Case Presentation: A 15-year-old girl presented with abdominal pain and distension for a few months. On examination, she had classical features of hypothyroidism. Abdominal and pelvic ultrasound revealed enlarged ovaries with multiple thin-walled cysts and mild ascitic fluid. On follow-up, abdominal ultrasound showed significant reduction of ovary size after 6 weeks of initiation of l-T4. Normal ovary size with complete regression of ovarian cysts was seen after 4 months.

Conclusion: Serial ultrasound in sOHSS associated with hypothyroidism showed regression of ovarian cysts and ovarian volume after 4 months whereas in other studies, it is reported to happen in various durations, presumably according to its etiology.

Learning Points: OHSS can rarely occur due to hypothyroidism.This type of OHSS can be simply treated by l-T4 replacement, rather than conservative management or surgery in severe cases.Ultrasound follow-up shows significant regression of ovarian size and cysts within 6 weeks of initiation of l-T4.Ultrasound follow-up shows normal ovarian size with complete resolution of ovarian cysts 4 months after treatment.