Pl go through sec.5(1) of the MB Act,1961 relating to payment of maternity benefit during the woman employee's actual absence on account of maternity and the method of its calculation.
If you analyse the sub section (1) of Sec.5 together with the explanation given thereof, you will understand exactly (1) what the maternity benefit prescribed is and (2) how it is to be calculated.
(1) It is the payment for the entire period of absence on account of maternity subject to a maximum of 26 weeks.
(2) It should be calculated at the rate of average daily wages payable to her for the days on which she has worked during the period of 3 calendar months immediately preceding the date of her such absence. Therefore, it implies that not merely the actual paid to her during the 3 months alone to be taken, but payable should also be taken into account for quantifying the benefit. In other words, if the rate of wages due for the preceding 3 months were revised subsequently with retrospective effect the calculation of maternity benefit should cover such revision also.
(3) Now, coming to your question which is whether the employer has to pay the benefit of prospective revision during the period of absence. In my opinion it is not necessary for the calculation is based on the earnings of the preceding 3 months only. From the day she rejoins duty after the maternity leave, her salary should be restored to the revised scale with prospective effect only.
Because of maternity leave a female employee does not get disentitled for any benefit given by the company to its employees. If variable pay is expressly linked with performance and deliverables then in that case she will be entitled for the period she has worked.