Hi I am trying to find out whether there is a specific provision that disallows foreign women from entering the country for the purpose of giving birth and obtaining U.S. citizenship for their children.

Many thanks.

DV: try INA 212 A 4 - public charge - if the inspector feels that the arriving alien has made no provision to pay her own darn hospital bill, the inspector can deny admission.
If the inspector does not believe that "tourism" is not the main focus of the purpose of admission, they can deny admission (INA 212 7 A I)
The problem with the crew members of a Korean or Filipino airline is they are admitted in a special lane and are generally not subject to nearly as much scrutiny as arriving tourists, etc.