Delayed delivery of the second twin after the miscarriage of the first foetus is very rare. Delayed second-twin delivery gives the opportunity for corticoid and antibiotics administration--procedures that decrease the infant morbidity and mortality. We report a case of the second twin's retention after miscarriage of the first at 17th week of pregnancy. The delay time was of 126 days (18 weeks). Pregnancy like this is at increased risk for all maternal complications, in particular intrauterine infection. Parents consent have to be obtained after informing them about advantages and risk of such procedure. The patient was treated with tocolysis, antibiotics, corticosteroids but not previous cervix cerclage has been performed. On regards of our experience and the data from literature we conclude that when observing fetal status and maternal condition, it is possible to delay the second twin's delivery long time after the miscarriage or birth of the first one thus giving the chance to the second twin to grow more mature. The main problem is imminent infection which defines the prognosis. Cerclage does not seem to be essential for better outcome.