Following images and videos show a case of isolated transient plantar edema seen at 26 weeks of otherwise normal pregnancy. Only mild edema the feet was observed at 30 weeks of the pregnancy. The child was born with normal feet without plantar edema. 

During the next pregnancy of the woman, the transient plantar edema was observed again.

Image 1, video 1: 26 weeks of pregnancy - plantar edema can be seen.