Ruyi had said before that Yu Hongxiu's fetal position was always good, meaning the baby was head down and could be safely delivered naturally. But now one of the twins' fetal position was wrong, what does that mean?
In ancient times, a caesarean section couldn't be performed. If the fetal position was abnormal, it would be a difficult birth, which might put both the mother and child in danger, hence the saying that giving birth was like passing through the Ghost Gate. But an abnormal fetal position wasn't completely hopeless. Experienced doctors or midwives could help the pregnant woman by massaging her belly to correct the fetal position, so by the same logic, they could also manipulate it into an incorrect position.