Women who abort their first pregnancy have a greater risk of having premature births in the future, according to a Scottish study.
Researchers from Aberdeen University analysed the medical records of 120,000 abortions, 460,000 births and 120,000 miscarriages in Scotland between 1981 and 2001.
Study author Professor Siladitya Bhattacharya told the British Science Festival that they found women who had terminated a pregnancy were at higher risk of a pre-term birth in their second pregnancy compared with women who had never been pregnant before. But they were less likely to have another premature baby than women who had suffered a previous miscarriage.
The study also compared surgical abortion –– performed by a doctor –– and medical abortion, which is done using a drug. They found women who had a surgical abortion were at greater risk of having a premature baby the next time they fell pregnant.
"Many women start their reproductive life with an abortion in their first pregnancy. Up until now what has not been entirely clear is the effect these abortions may have on subsequent childbearing," Bhattacharya said.
"We found that women who had an induced abortion in their first pregnancy were more at risk of maternal and perinatal risks in comparison with women who had had a live birth or no previous pregnancy."
Professor Bhattacharya said he believes surgical abortion could damage a woman's reproductive organs.
"What we think is going on here is that if there is a greater degree of trauma involved with an abortion procedure that probably is more likely from a physiological point of view to damage the cervix that leads to spontaneous pre-term birth later on, because that is the weakness that allows a pregnancy to slip away," he said.
"The hypothesis is that a medical termination is less traumatic than a surgical termination. Bearing in mind all the caveats, it does seem to suggest that there is scope for growing medical abortion," he said.
According to Family Planning Victoria, about 34 percent of women aged 20 to 29 have had an abortion and an estimated 80,000 abortions are performed in Australia each year.
Adjunct Associate Professor Jo Wainer from the Monash University Faculty of Medicine, Nursing and Health Sciences, told ninemsn that medical abortion had only just been approved for use in Australia and that women needed to be informed about this study.
"It's really important that women know about the data about medical abortion being safer for subsequent pregnancies than surgical abortion," she said.
Wainer conceded it was unlikely to change a woman's decision about having an abortion.
"Women make decisions about whether to continue a pregnancy or terminate it for very serious reasons," she said.
"They need to be informed about the findings of this study because it is a very high quality study and it does identify a small risk to the second pregnancy after a surgical abortion but not after a medical abortion."