Since what week there is an attachment of a fetus to a cord or navel of mother? Thanks for...

[Anja]

Since what week there is an attachment of a fetus to a cord or navel of mother?
Thanks for the answer.

[Pasenjuk A.M.]

The fetus is attached not to a cord or navel of mother, and a cord or navel - by several vessels to a chorion, (which then becomes a placenta - the special organ providing a delivery of a fetus) on term of 6 7 weeks from the first day of last menses