Is a pregnant women restricted to visit a death house?

Though Iam modern in thoughts,there is one query that is haunting me.I hope IL's to throw their opinion on the same.
My friend's sister who was pregnant for 7 months(with second child) passed away along with the baby in womb due to sudden illness.Though it has been an year passed,some people seriously suggest me not to go that house as Iam also pregnant with my first child.Iam deaf to all these beliefs but old age people gives me instructions like dont eat anything from that house,dont visit that house,be away from anything that is linked with those family members etc..I feel very bad to hear all that as my friend's sister who passed away is harmless and innocent girl.How can i excuse everytime to my best friend about not visiting her house as she is my neigbour too.I have seen people in hospitals clipping a neem leaf on their hair or carrying an iron nail with them to ward off evil energies on their way.My grand mother says not to open the entrance door if anyone knocks after late evening.
I would like to know if these superstition or old age beliefs are true?How does it affect the baby?Kindly free my mind from the same!