skip to main content

Ovarian torsion — USMLE Step 3 MCQ

Instant feedback + full explanation. One question, done properly.

HardOB/GYN (prenatal care, contraception, screening)Ovarian torsionUSMLE Step 3

A monochorionic diamniotic twin pregnancy at 21 weeks has polyhydramnios in the recipient sac, oligohydramnios in the donor sac, and a nonvisualized donor bladder. Dopplers are otherwise normal. What is the preferred treatment?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: DRefer urgently for fetoscopic laser photocoagulation of placental anastomoses

The best answer is “Refer urgently for fetoscopic laser photocoagulation of placental anastomoses”. A nonvisualized donor bladder establishes Quintero stage II TTTS. Between 16 and 26 weeks, fetoscopic laser treatment of communicating placental vessels is standard. Amnioreduction can be considered when laser is unavailable but does not correct the underlying vascular mechanism.

Reference: SMFM Consult Series #72: Twin-Twin Transfusion Syndrome and Twin Anemia-Polycythemia Sequence: https://publications.smfm.org/publications/574-society-for-maternal-fetal-medicine-consult-series-72/