As your HR department has not communicated to you anything about under-performance, I recommend you writing a mail to them and asking clarification on under what parameters the performance was below the level. Include your past achievements in this mail. Secondly, also mention that your Manager has never given any feedback anytime on your under-performance. Therefore, what is the source of their information?
Going by the replies of your post, prima facie it appears that mail from HR could be a ploy to remove you. However, it is too early to make final conclusion.
Nobody reports to you is a positive feature of your case. You will be considered as "workman" under the provisions of Industrial Dispute Act, 1947 and if need be, you may approach Labour Officer of your area to explain the case of harassment.However, wait till you receive reply to your mail. In the meanwhile, find out where is the Labour Office where your company is located, go there and understand overall how do they take up cases of labours, visiting hours, how the complaints are made etc. When there is actual need to put up application, you may write application in English need to talk in Marathi. If you do not know this language then you need to take someone with you who knows Maharashtra's official language.
By the way, 30-day is just a monitoring period. However, should it be considered as countdown? Overall what is the culture of your company? How the people are removed? Are they given notice period on and above this monitoring period or both are merged together?
In the meanwhile, start taking printouts of all the communication with the HR Department. Keeping records in the hard copies is always important.
Let me reiterate about maintaining calm and tension free when you are carrying. Healthy development of foetus is important and for this no one but yourself is responsible.
For HR Professionals: - While sending official communication to the employee on under-performance, not mentioning the parameters of under-performance or not providing the evidence of under-performance is unprofessional. That this should happen in IT company, a sector is well-known to look down upon other sectors, speaks volumes. These type of emails are never sent by lower level employees. Even if sent, these are sent with countenance of higher HR officials. That they are also equally unprofessional. This is highly reprehensible.
4th November 2016 From India, Bangalore