due date

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The date at which an infant is expected to be born, calculated from the date of the last menstrual period.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The date on which a pregnant woman is expected to give birth.
• noun The date of payment in financial arrangements.
• noun The date by which a book (or other item) borrowed from a library must be returned.
• noun The date by which a task is supposed to be completed.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the date on which an obligation must be repaid