What's more, after an abortion, women are 30 per cent more likely to have mental disorders as compared to other ladies, the research published in the British Journal of Psychiatry has revealed.
The researchers came to the conclusion after reviewing 500 women.
According to Professor David Fergusson, who led the research, the findings have "important implications," because more than 90 per cent of British abortions were authorized on the grounds that keeping an unwanted baby would cause the mother mental health problems.
"This evidence clearly poses a challenge to the use of psychiatric reasons to justify abortion. There is nothing in this study that would suggest that the termination of pregnancy was associated with lower risks of mental health problems than birth," the Daily Mail quoted him, as saying.
"For some women, abortion is likely to be a stressful and traumatic life event which places them at a modestly increased risk of a range of common mental health problems," the expert added.
However, according to David's colleagues at the University of Otago, New Zealand, abortion's overall effect on mental health was small.
They estimate it is responsible for between 1.5 per cent and 5.5 per cent of disorders.
Another study has shown that women who lose a baby when they are 21 - either through an abortion or a miscarriage - are three times more likely to develop a drug or alcohol problem than others.
Researcher Kaeleen Dingle, of the University of Queensland, Australia, said: "Abortion and miscarriage are stressful life events that have been shown to lead to anxiety, sadness and grief and, for some women, serious depression and substance use disorders."