The malays believe that salted fish and prawns have to be avoided totally for the first 40 days after birth as they can cause allergy and itchiness. Is this true?

I asked my mom about this and she said that it's because prawns and shellfish in general are bottom-feeders in the ocean so they tend to carry more bacteria compared to other seafood. Thus, there is a belief that shellfish, prawns etc should be avoided because it can cause wounds and surgery marks to itch and be inflammed.