What the term " Obstetric week " means and than he differs from usual week?...

[Elena]

What the term " Obstetric week " means and than he differs from usual week?

[Elena]

Pregnancy lasts 40 obstetric weeks. 1 I week begin in the first day of last menses. In a week also 7 days, but the beginning or a weekend accordingly can not coincide with Monday or Sunday

[Pasenjuk A.M.]

Obstetric week has 7 days and it is considered from the first day of last menses