Two Water Bags.
Unusual appearance of two simultaneous water bags. No clinical significance. The darker blue-black bag on the right is the allantoic sac and contains allantoic fluid (fetal urine, in this case tinged by blood), and the amniotic sac on the left containing pale gray amniotic fluid. The amnion is contained within the allantois. The allantois ruptures first. It is likely that some allantoic fluid was trapped in a pocket of the allantoic membranes. [The bedding in the picture is recycled (news) paper, some of which clings to the bottom of the amniotic sac].
Blough E (2007)