Question Summary:
Is it necessary to adhere to the following cultural customs?

Question Detail:

 
I am married and working in Lahore, Pakistan. We are expecting our first baby in August 2015. Both of our parents and relatives are in Karachi, Pakistan.
My parents are insisting that since its a first baby, (1) all the hospital related expenses should be borne by my wife's parents. Additionally, (2) my wife should stay in her parents' home for atleast 40 days after delivery so that they take care of her. My parents say that both of these are part of our culture and values and must be adhered to.
My point of view is that I should bear the hospital expenses. Secondly, if its not possible for me to make transport arrangements from Lahore to Karachi and vice versa prior to and post delivery, then I should do it in Lahore only where my mother in law can come for support and care.
Q1) Is it alright if my parents ask my wife's parents to bear the hospital expenses?
Q2) Is it must that my wife should stay at her parents home even though we live in a different city and it might not be easy making traveling arrangements?

Answer :

In the Name of Allāh, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh. 
In principle, as a father and guardian of your child, you are responsible to provide any maintenance necessary for the child[1].
It is necessary to understand that as a Muslim, we are bound to practice and abide by the teachings of our Shar‘iah in all aspects of our lives, and not by cultural customs and values that have no basis in Shar‘iah.
As such, it is not necessary for the wife’s family to bear all expenses for the first child of the family, nor is it necessary for the wife to remain in the home of her parents’ after the first 40 days of delivery as none of the aforementioned hold any basis in Shar‘iah.
However, if the wife is in need of assistance from her family, she may choose to stay with her parents after delivery for however long necessary. Furthermore, the wife’s family may offer their assistance in the hospital expenses as a kind gesture, however, it should not be deemed necessary to do so. In such an issue, there should be mutual agreement between the husband and wife. The parents’ of the spouses have no right in issues mutually agreed by the spouses.
 
 
And Allah Ta‘āla Knows Best
Fahad Abdul Wahab
Student Darul Iftaa
USA
Checked and Approved by,
Mufti Ebrahim Desai                                                                                                                                                                                                                
www.Daruliftaa.net