Identical twins Nancy and Margo receive a treatment while still in the womb through what is described as a world-first medical trial, according to BBC News. The twins’ case involves a rare pregnancy condition that can place the fetuses at serious risk. Doctors use a procedure in utero to address the problem during the pregnancy, and the report says the treatment helps the twins survive and develop normally after birth. The two girls are identified as Nancy and Margo, and the timing of the intervention is characterized as occurring during gestation rather than after delivery. The coverage emphasizes that the approach is pioneering and part of a trial aimed at testing the safety and effectiveness of the technique for this uncommon condition. The reports available here focus on the outcome for the twins and the trial’s novelty, without detailing the full medical protocol or the specific condition in the provided text. Overall, the sources agree that the in-womb procedure is the key factor credited with improving the pregnancy outcome for the identical twins.