Schizophrenia Risks - cont'd....

Prenatal factors

What happens to you before you’re born — or during the process of birth- can affect you all your life. The likelihood of schizophrenia developing has been linked to several prenatal (before birth) factors:

·         The age of the birth father: One prenatal risk factor that’s been linked to schizophrenia is the age of the birth father. Children with fathers who are over the age of 50 are three times more likely to develop schizophrenia than children whose fathers are under 30 years old at the time of their birth. Some researchers have suggested that this may be the result of sperm mutations that occur with advancing age.

·         Influenza: Studies have shown that children born to mothers who contracted the flu while pregnant (especially during the second trimester) also have a greater chance of developing schizophrenia.

·         Starvation: Maternal starvation is linked to increased risk of schizophrenia in offspring. Starvation can occur either because of poverty or because of eating disorders such as anorexia.

·         Stress: Recently, a large epidemiological study looked at stressors such as the death of a close relative or a diagnosis of cancer, heart attack, or stroke in a close relative as risk factors for having children who would develop schizophrenia later in life. Only one of these factors increased risk: The risk of developing schizophrenia or a related disorder was 67 percent greater among the children of mothers who experienced the death of a close family member during the first trimester than those who did not have that stress. The vast majority of fetuses exposed to these prenatal environmental stressors did not develop schizophrenia, leaving the perplexing question of why some did and others didn't still unanswered.

Schizophrenia Risks

Obstetrical and birth complications

The ways in which birth complications double the risk for schizophrenia are not known. But several studies show that various obstetrical and birth complications do increase risk.

A statistical review of multiple studies looking at the link between obstetric complications and schizophrenia found three groups of complications associated with the disorder:

·         Complications of pregnancy, including bleeding, diabetes, Rh incompatibility, and pregnancy-induced high blood pressure

·         Abnormal fetal growth and development, including low birth weight, cardiovascular congenital anomalies, and small head circumference

·         Complications of delivery, including lack of uterine muscle tone, inadequate oxygen intake by the baby, and emergency cesarean section (C-section)

·         Other life experiences

Although parents have been let off the hook as far as finger-pointing blame for schizophrenia goes, the current consensus is that other environmental stressors and stress in general may contribute to the onset of schizophrenia. For example, urban life, geographic migration, and poverty are all associated with increased rates of schizophrenia.

Other studies have shown that individuals with schizophrenia smoke marijuana more often than the general population. Some prospective studies now show that smoking marijuana (before the onset of psychotic symptoms) increases the likelihood of schizophrenia by two to four times. On the other hand, the overwhelming majority of people who smoke marijuana don’t develop schizophrenia.