RhIg is crucial in preventing which complication in Rh-negative individuals?

RhIg, or Rho(D) immune globulin, is essential in preventing hemolytic disease of the newborn (HDN) in Rh-negative individuals. This condition occurs when an Rh-negative mother carries an Rh-positive baby, leading to the mother's immune system potentially producing antibodies against the baby's Rh-positive red blood cells. If these antibodies cross the placenta, they can destroy the infant's red blood cells, resulting in anemia, jaundice, and even more severe health complications.

When Rh-negative mothers receive RhIg during and after pregnancy, it helps to prevent their immune systems from sensitizing to Rh-positive blood cells. By doing so, RhIg effectively reduces the risk of the mother developing antibodies that could harm her Rh-positive fetus in subsequent pregnancies.

The other options listed do not relate to the specific immunological mechanism involved in Rh factor incompatibility. Diabetes, kidney failure, and heart attack each have distinct causes and risk factors unrelated to Rh factors in pregnancy. Therefore, RhIg plays a pivotal role specifically in preventing hemolytic disease of the newborn, making this the correct response.