In developed countries, about 6.7 million abortions are performed every year, with a large proportion performed on teens aged 19 years or younger, researchers wrote in the study published in Canadian Medical Association Journal.
In Canada, the teen pregnancy rate is 28 per 1,000, with more than 50 per cent of these ending in abortion, they said.
"Research shows there is an association between mothers and daughters in the timing of a first pregnancy ending in a live birth," according to Joel Ray and Ning Liu from the Institute for Clinical Evaluative Sciences in Canada.
The large study included data on 431,623 daughters born in Ontario obtained from the Institute for Clinical Evaluative Sciences (ICES) and linked to other databases that provided information on mother-daughter pairs.
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There were 73,518 daughters whose mothers had had at least one abortion (exposed group) and 358,105 daughters whose mothers had none (unexposed group).
In the exposed group, the probability of having an abortion during their teenage years was 10.1 per cent, compared with 4.2 per cent in the unexposed group.
As the majority of those abortions (94.5 per cent) occurred before 15 weeks gestation, it is unlikely that the reason was a genetic or birth defect in the foetus in most cases and it may be reasonable to assume social indications.
"We don't know what factors cause this association, as it was beyond the scope of our study," said Liu.
"Previous studies have found a higher likelihood of teen abortion if a young woman has greater social challenges, including poor school performance, separation from a biological parent, lower parental education, and receipt of income support," said Liu.
"Further research is needed to determine if strategies that engage parents could reduce unprotected sex in teens, as well as to understand the major factors that contribute not only to teen pregnancy, but also to the decision to have an abortion or maintain a pregnancy," said Ray.