You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is In asymmetrical IUGR which organ is not affected – and explain in detail?
IUGR is classified as
1) Symmetric IUGR

Reduced growth is an asymmetric → head circumference, length and weight equally affected.
Has earlier onset.
Is associated with diseases that seriously affect fetal cell number, such as conditions with chromosomal, genetic malformation, teratogenic, infectious or severe maternal hypertensive etiologies.

2) Asymmetric IUGR

Reduced growth is asymmetric with relative sparing of head growth.
Has late onset.
Is associated with poor maternal nutrition or with late onset/exacerbation of maternal vascular disease (preeclampsia, chronic hypertension).