Dr. Dick Swabb also indicated that factors like taking synthetic hormones, leading a stressful life and living in a heavily-polluted area can also affect the probability of having a child who turns out to be gay.
In Swabb’s book, We Are Our Brains, he argues the brain’s development during pregnancy and early childhood is linked to the kind of people that individuals become in adulthood.
"Pre-birth exposure to both nicotine and amphetamines increases the chance of lesbian daughters," Swabb said. "Pregnant women suffering from stress are also more likely to have homosexual children of both genders because their raised level of the stress hormone cortisol affects the production of foetal sex hormones."
The leading neuroscientist also said that alcohol use can lead to a possible lower IQ in children.
"In women who drink a lot, cells that were meant to migrate across the foetal brain can end up leaving the brain altogether," Swabb said. "Even in women who drink just a glass of wine a day we see effects [such as] lower IQ and hyperactivity. There is no safe level."
[The Sunday Times]