Thanks for the link.
I noticed this at the bottom of the same page:
"Abortion
The medical records of 300,858 first-time mothers in Finland demonstrate a link between abortion and preterm birth. Human Reproduction reports that Finnish women were slightly more likely to give birth prematurely if they had already undergone one or more induced abortions. Those who had three or more abortions were three times as likely to give birth before 28 weeks. —D.J.D."