Abortion and risk to the health of later babies

New analysis of old data published in the January 2008 issue of the Journal of Epidemiological Community Health (free abstract) has confirmed the association between induced abortions and later premature birth and low birth weight babies. Babies born prematurely and/or weighing less that normal are much more likely to die in the first month or have severe health problems like lung disease or brain damage.

However, the focus of the original research is based on self-reported information from over 45,500 moms who gave birth from 1959 to 1966 and the records don't tell us whether the mothers had spontaneous abortions (miscarriages) and induced intentional abortions. The authors do find that increased numbers of miscarriages or abortions increase the risk of low birth weight at full term and of premature birth:

Compared with women with no history of abortion, women who had one, two and three or more previous abortions were 2.8 (95% CI 2.48 to 3.07), 4.6 (95% CI 3.94 to 5.46) and 9.5 (95% CI 7.72 to 11.67)times more likely to have LBW, respectively. The risk for PB was also 1.7 (95% CI 1.52 to 1.83), 2.0 (95% CI 1.73 to 2.37) and 3.0 (95% CI 2.47 to 3.70) times higher for women with a history of one, two and three or more
previous abortions, respectively.

The new information from the JECH is nearly 50 years old and can't distinguish between miscarriages and induced abortions, so it doesn't really tell us much about the risk from today's elective abortions or give proof that induced abortion is risker than miscarriage. I'm afraid that that is the emphasis of media reports like those in Time and Medical News Today. (Although they don't note the surprising result that the study found no association between smoking and premature birth, although there was a significant association between smoking and low birth weight.)

However, the authors review results from other studies which do make distinctions between the mothers who had previous induced abortions and those who had miscarriages. Those studies do show an association between induced intentional abortions and low birth weight, term low birth weight, and premature birth. Instead of the 300 to 900% risk over full term live birth, most found at least a small 1.1 to 1.4 (10% to 40%) increased risk after one intentional induced abortion and up to 3 times the risk after 2. While there is also a risk after miscarriage, miscarriage can't be helped. The variables which can be changed - not those that can't be - are matters for public health policy.

And fewer of our children will have to die for it.