due date; expected delivery date
Medical and everyday term for the date a baby is expected to be born.
The due date is the 10th of next month.
I confirmed the expected delivery date with the doctor.
予定日 is a more general term for a scheduled date, while 出産予定日 specifically refers to a baby's due date.
Compound of 出産 (childbirth) + 予定 (schedule) + 日 (day).