(1) Subject to the provisions of this Act, every woman employed in an establishment shall be entitled to, and her employer shall be liable for, the payment of maternity benefit at the rate of her wages last paid during the period of six weeks immediately preceding and including the day on which she delivers the children for each day of six weeks succeeding the day:
Provided that a woman shall not be entitled to maternity benefit unless she has been employed in the establishment of the employer from whom she claims maternity benefit for a period of not less than four months immediately preceding the day on which she delivers the child.