Laser Photocoagulation is the Standard Treatment
For this 24-week pregnant woman with monochorionic twin pregnancy and TTTS, fetoscopic laser photocoagulation of placental vascular anastomoses (Option C) is the most appropriate next step in management. 1, 2
Why Laser Surgery is the Definitive Answer
The Society for Maternal-Fetal Medicine explicitly recommends fetoscopic laser surgery as the standard treatment for stage II through stage IV TTTS presenting between 16 and 26 weeks of gestation, which directly applies to this 24-week patient. 1, 2
This therapy provides superior survival rates compared with expectant management or serial amnioreduction, with dual survivors expected in 50-70% of cases and at least one survivor in 70-90% of cases. 1, 2
Fetoscopic laser surgery is the only therapy that directly addresses the underlying pathophysiology by photocoagulating intertwin placental anastomoses, functionally "dichorionizing" the placental circulation and eliminating the root cause of TTTS. 1, 3
Why Other Options Are Inappropriate
Expectant Management (Option B) is Inadequate
The natural history of advanced TTTS (stage III) is bleak, with reported perinatal loss rates of 70-100%, particularly when presenting at ≤26 weeks. 4
While stage I TTTS may be managed expectantly (with >75% remaining stable or regressing), this patient requires intervention given the diagnosis at 24 weeks with evidence of TTTS. 4
Termination (Option A) is Not Indicated
- With modern fetoscopic laser therapy achieving at least one survivor in 70-90% of cases, termination is not appropriate when effective treatment exists. 1
Cesarean Section (Option D) is Premature
At 24 weeks gestation, immediate delivery would result in extreme prematurity with very poor neonatal outcomes. 4
The goal is to treat the TTTS in utero and prolong the pregnancy to improve survival and reduce morbidity. 1
Technical Considerations for Laser Surgery
The Solomon technique is preferred, which involves linear photocoagulation along the intertwin vascular equator after ablating visible anastomoses, reducing the risk of recurrent TTTS or twin anemia-polycythemia sequence (TAPS). 1, 2
The procedure uses percutaneous access and can be safely performed with maternal intravenous sedation and local anesthesia or regional anesthesia. 1, 2
Expected Complications and Ancillary Management
Preterm premature rupture of membranes (PPROM) is the most common complication, occurring in approximately 25% of cases. 1, 2
Recurrent or reversed TTTS or TAPS may complicate over 10% of pregnancies post-laser. 1
Administer antenatal corticosteroids for fetal lung maturation at 24 weeks gestation, particularly given the increased risk of preterm delivery following the procedure. 1, 2
Major neurologic morbidity occurs in 4-18% of survivors at 2 years of age, though most pediatric survivors have normal neurologic outcomes. 1, 2
Critical Pitfall to Avoid
Do not delay referral to a specialized fetal care center with expertise in fetoscopic laser surgery. 2 The patient should be immediately referred to a maternal-fetal medicine specialist at a center experienced in performing this procedure, as delays can result in progression to higher stages with worse outcomes. 2