There are certain precautions that many women take when they become pregnant in order to protect their unborn child from avoidable sicknesses. Refraining from raw fish, eggs, alcohol and smoking cigarettes are some common steps that can lower an unborn child's risk for permanent physical impairments — all supported by empirical scientific findings. But then there are some beliefs about pregnancy that seem to be way in the deep end. A professor of neurobiology at Amsterdam University named Dick Swaab recently claimed that smoking cigarettes and being stressed while pregnant might lead to a mother influencing a number of things, including the sexuality of the fetus. In other words, Swaab claimed that smoking while pregnant might make your child gay.

According to The Sunday Times Swaab writes in his new book, called We Are Our Brains, that “Factors ranging from taking synthetic hormones to leading a stressful life can raise the chance of having a child who turns out to be gay.” He specifically says that drinking or taking drugs can lower a child’s IQ and smoking or taking synthetic hormones could increase the chance of a girl becoming a lesbian or bisexual —specifically synthetic estrogen, which women took between 1939 and 1960 to prevent miscarriages. "Pre-birth exposure to both nicotine and amphetamines increases the chance of lesbian daughters," Swaab said to The Sunday Times.

The American Academy of Child & Adolescent Psychology reports that drinking during pregnancy is the most common cause of birth defects causing brain damage to an unborn fetus in the United States. Other negative effects such as facial deformities, slow development, and neurological problems can also occur. However, no study has shown a correlation between cigarette smoking during pregnancy and the sexuality of a child.

Swaab also believes that having older brothers will increase the chance that boys will become gay because during pregnancy; the mother’s immune system will have a stronger response to male hormones with each son, thus increasing the chances of having a gay son. Moreover, Swaab also believes sexuality is determined in the womb and cannot be changed regardless of lifestyle, the Daily Mail reported. “Children brought up by lesbians aren’t more likely to be homosexual. Nor is there any evidence at all for the misconception that homosexuality is a ‘lifestyle choice,’” Swaab said.

This news might have some gay rights advocates fuming, but others are welcoming the idea because of the professor's biological claim. “It is a slap down for religious and political homophobes. If being gay is mostly or wholly determined by biological factors prior to birth, it is immoral to condemn or discriminate against lesbians and gay men,” said Peter Tatchell, gay rights campaigner.