In the Journals

Maternal abortions linked to future abortion in adolescent daughters

Adolescent females are more likely to induce abortion when their mother has a history of the procedure 4 years before their birth up to 12 years after their birth, according to a study published in CMAJ.

“Each year, about 6.7 million induced abortions are performed in developed nations. A considerable proportion of these procedures are among teens aged 19 years or younger,” Ning Liu, MSc, from the Institute of Health Policy, Management and Evaluation at the University of Toronto, and colleagues wrote. “Teen induced abortion may be influenced by factors at the individual, family, peer and community levels.”

To examine if teenage daughters of mothers who have had an abortion are more likely to also have an abortion, the researchers conducted a retrospective population-based cohort study that included females born between 1992 and 1999. Those included were born in Ontario and were assessed for data collected between the ages of 12 and 20 years regarding induced abortions. Liu and colleagues then examined whether their mothers had induced abortion 4 years before their daughter’s birth to 12 years after their daughter’s birth.

Using Cox proportional hazard models, the researchers assessed the risk of a teenager inducing an abortion in comparison to their mother’s history of abortion. Maternal age and place of birth, as well as mental and physical health concerns of daughters, were examined for adjusted HRs. Additionally, Liu and colleagues assessed whether mothers and daughters lived together, the rate of teen induced abortion within their neighborhood, rural or urban location and income level.

Of the 431,623 daughters included in the study, the cumulative probability of abortion in teenagers whose mother had an abortion was 10.1% (95% CI, 9.8%-10.4%). When mothers had no induced abortions, teenagers had a cumulative probability of 4.2% (95% CI, 4.1%-4.3%). The researchers observed an aHR of 1.94 (95% CI, 1.86-2.01).

When mothers had one abortion, the aHR of their adolescent daughter inducing abortion was 1.77 (95% CI, 1.69-1.85). The ratio increased as mothers induced more abortions, with the aHR increasing to 2.04 with two maternal abortions (95% CI, 1.91-2.18) and 2.39 with three maternal abortions (95% CI, 2.19-2.62). When mothers induced four or more abortions, this aHR increased to 2.54 (95% CI, 2.33-2.77).

“The mechanisms for intergenerational induced abortion are unclear, and this study was not designed to assess such details,” Liu and colleagues wrote. “Several previous studies explored the determinants of teen abortion and reported that a woman is more likely to have a teen induced abortion if she has mental illness or a substance use disorder, poor school performance, teenage parents at her own birth, parents with a lower level of education or receiving income support, and family disruption resulting in separation from biological parents. These factors should be take into consideration when studying intergenerational induced abortion.”  – by Katherine Bortz

Disclosure: The authors report no relevant financial disclosures.

Adolescent females are more likely to induce abortion when their mother has a history of the procedure 4 years before their birth up to 12 years after their birth, according to a study published in CMAJ.

“Each year, about 6.7 million induced abortions are performed in developed nations. A considerable proportion of these procedures are among teens aged 19 years or younger,” Ning Liu, MSc, from the Institute of Health Policy, Management and Evaluation at the University of Toronto, and colleagues wrote. “Teen induced abortion may be influenced by factors at the individual, family, peer and community levels.”

To examine if teenage daughters of mothers who have had an abortion are more likely to also have an abortion, the researchers conducted a retrospective population-based cohort study that included females born between 1992 and 1999. Those included were born in Ontario and were assessed for data collected between the ages of 12 and 20 years regarding induced abortions. Liu and colleagues then examined whether their mothers had induced abortion 4 years before their daughter’s birth to 12 years after their daughter’s birth.

Using Cox proportional hazard models, the researchers assessed the risk of a teenager inducing an abortion in comparison to their mother’s history of abortion. Maternal age and place of birth, as well as mental and physical health concerns of daughters, were examined for adjusted HRs. Additionally, Liu and colleagues assessed whether mothers and daughters lived together, the rate of teen induced abortion within their neighborhood, rural or urban location and income level.

Of the 431,623 daughters included in the study, the cumulative probability of abortion in teenagers whose mother had an abortion was 10.1% (95% CI, 9.8%-10.4%). When mothers had no induced abortions, teenagers had a cumulative probability of 4.2% (95% CI, 4.1%-4.3%). The researchers observed an aHR of 1.94 (95% CI, 1.86-2.01).

When mothers had one abortion, the aHR of their adolescent daughter inducing abortion was 1.77 (95% CI, 1.69-1.85). The ratio increased as mothers induced more abortions, with the aHR increasing to 2.04 with two maternal abortions (95% CI, 1.91-2.18) and 2.39 with three maternal abortions (95% CI, 2.19-2.62). When mothers induced four or more abortions, this aHR increased to 2.54 (95% CI, 2.33-2.77).

“The mechanisms for intergenerational induced abortion are unclear, and this study was not designed to assess such details,” Liu and colleagues wrote. “Several previous studies explored the determinants of teen abortion and reported that a woman is more likely to have a teen induced abortion if she has mental illness or a substance use disorder, poor school performance, teenage parents at her own birth, parents with a lower level of education or receiving income support, and family disruption resulting in separation from biological parents. These factors should be take into consideration when studying intergenerational induced abortion.”  – by Katherine Bortz

Disclosure: The authors report no relevant financial disclosures.