Termination of Employment by the company due to pregnancy

Dear Ma'am/Sir
I have been associated with a company for more than an year. Recently, the company has converted our employment to contract and at the time of signing the contract, the HR told me verbally that I will be given 3 months paid and 3 months unpaid leave of maternity.
But now, they are terminating the services of more than 80% staff of our department stating that parent company is asking them to do so. And we 80% people will become jobless in a month.
I have been the efficient employee of the department, I have got to know the reason that they are ousting me due to my maternity issues.
I am worried as I have so much obligations to meet.
What recourse I can take in this matter?
Please advise