Ruysch gives an account of a surgeon's wife at Amsterdam, in 1686, who was delivered of a strong child which survived, and, six hours after, of a small embryo, the funis of which was full of hydatids and the placenta as large and thick as one of three months.

Ruysch accompanies his description with an illustrative figure.

At Lyons, in 1782, Benoite Franquet was unexpectedly delivered of a child seven months old; three weeks later she experienced symptoms indicative of the existence of another fetus, and after five months and sixteen days she was delivered of a remarkably strong and healthy child.
Baudeloque speaks of a case of superfetation observed by Desgranges in Lyons in 1780.

After the birth of the first infant the lochia failed to flow, no milk appeared in the breasts, and the belly remained large.

In about three weeks after the accouchement she had connection with her husband, and in a few days felt fetal movements.