Differential diagnosis, investigations and treatment
We diagnosed vasa praevia. Emergency caesarean section was performed.
We predicted that the foetal vessels were running on the anterior wall of the lower uterine segment. When the lower uterine segment was incised transversely, we were very careful not to injure the foetal vessels before delivery. Careful blunt entry using haemostats and fingertips was performed. The amniotic membrane was exposed without rupture of the membrane and injury to foetal vessels. Foetal vessels were found in the exposed amniotic membrane (Figure 2A). Because the vessels were running on both sides of membrane, the amniotic membrane was ruptured at the central part. A mature female baby was safely delivered. The neonate had a birth weight of 2890 g (appropriate for gestational age) and Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. We examined the intrauterine findings after delivery. As we diagnosed before the operation, a section of the foetal vessels was meandering and running over the internal cervical os (Figure 2B). Both the placental position and the site of the umbilical cord insertion were above the low transverse incision scar (Figure 2C).