Gay couples wait in lineto apply for a marriage license in Salt Lake City
Tarah Camarillo (L-R), her partner Nicole Barnes, Leighton Hilburn and his partner Preston Perry wait in line with hundreds of other people to apply for a marriage license at the Salt Lake County Clerks office in Salt Lake City, Utah, December 23, 2013. Reuters/Jim Urquhart
Tarah Camarillo (L-R), her partner Nicole Barnes, Leighton Hilburn and his partner Preston Perry wait in line with hundreds of other people to apply for a marriage license at the Salt Lake County Clerks office in Salt Lake City, Utah, December 23, 2013.

According to a neuroscientist, women who smoke during their pregnancy may well be held responsible for their children's homosexual orientation.

Dick Swaab from the Amsterdam University claims that smoking habits and stress during pregnancy play a highly influential role in forming the IQ and sexuality of the child. The neurobiology professor also said that taking drugs, drinking and living in a highly polluted area also affect the children later in their life.

According to Mr Swaab's theories, smoking and consuming synthetic hormones may increase the possibilities of girls being bisexual or lesbians. He also believes that boys tend to be homosexual if they have more number of older brothers. The reason he cites is that the mother tend to be develop immune system against stronger male hormones. Mr Swaab expressed his views to the Sunday Times that the possibilities of having lesbian daughters would increase if the mother had amphetamines and nicotine during her pregnancy.

Even mothers who suffer from stress tend to give birth to children with homosexual orientations. This applies to both genders whether the child is a boy or a girl. The high level in cortisol, the stress hormone, influences the sex hormones of the foetus; he said.

Mr Swaab referred to studies of women during 1939 to 1960. The women who consumed synthetic oestrogen for reducing the possibilities of miscarriage had more chances of giving birth to daughters who were either lesbian or bisexual. He also added that women with heavy drinking habits make cells leave the brain of the foetus instead of migrating across them.

Living in highly polluted areas ends up causing risks of autism among children. Mr Swaab says that genetics are the most important factor even though lifestyle does influence the unborn child quite a lot. According to him, there are researches that have already proved the direct connection between adult lifestyles and the foetal brain development.

Mr Swaab delineated how a mother's lifestyle might influence the baby in his book, We Are Our Brains.