What ?

Why is this show titled pavitra rishta
There is nothing pavitra left
Lets start with the second generation :

Archana's biological daughter has been in love with a boy she grew up with for all her life.
Archana's adopted daughter began working with that boy and they fell for each other.
Purvi (adopted) ended up getting engaged to Arjun after Arjun called off his engagement with Ovi (biological)
Until then : love is pure. Love triumphs all obstacles
Pavitra still applies ..

Ovi promises Purvi that she will give her Archana her family back with whom she drifted apart due to misunderstandings ion exchange of her love.
Purvi sacrificed.
Arjun married Ovi
Still pavitra - sacrificed for her mommy dearest

Now Purvi tells Arjun to consummate his marriage with Ovi
He did.
Not pavitra , because he gave in to her physically not mentally

After 6 months Purvi is pregnant (6 months)
Ovi (4 months)
Biological father : Arjun
Truth unveils to viewers that Arjun and Purvi consummated before getting married
All pavitrata gone.

Purvi married a doctor
Arjun is with Ovi
Ovi loses her child so Purvi gives her her own child
Not pavitra because Ovi has the capability to be a mother again
Why would a mother give away her child like that
Yes Arjun is the biological father of purvis baby
But how is Arjun not knowing the reality pavitra ?
Pavitrata 0%

So much so, now both sisters breast feed the baby
Ovi doesn't know her real child is dead
Ovi doesn't know she is nursing her husband's and his ex girlfriend's
Offspring.
Any expectation of logic is long lost from this show