An episiotomy is a surgical incision used to enlarge the vaginal opening to help deliver a baby. An episiotomy may be needed for any of the following reasons: 1  Birth is imminent and the perineum hasnât had time to stretch slowly. 2  The babyâs head is too large for the vaginal opening. 3  The baby is in distress. 4  The mother needs a forcep or vacuum assisted delivery.
A hypersensitive immune system is one which overreacts to a stimulus. A normal immune system reacts when the body identifies a foreign protein such as proteins on the outside of bacteria.This foreign material which invokes the immune response is called an antigen.mail Article. A hypersensitive immune system is one which overreacts to a stimulus. A normal immune system reacts when the body identifies a foreign protein such as proteins on the outside of bacteria. This foreign material which invokes the immune response is called an antigen.
Princeton's WordNet(0.00 / 0 votes)Rate this definition: hypersensitivity reaction(noun) an inappropriate and excessive reaction to an allergen (as pollen or dust or animal hair or certain foods); severity ranges from mild allergy to severe systemic reactions leading to anaphylactic shock. Chaldean Numerology.