Low birth weight in relation to multiple induced abortions.
BACKGROUND
Most studies report that a single induced abortion does not increase risk for delivering a low birth weight infant in a subsequent pregnancy. However, the effect of multiple abortions has not been adequately evaluated.


METHODS
This relationship was studied in 6541 White women who delivered their first child between 1984 and 1987. We compared the frequencies of low birth weight (less than 2500 g) among infants born to 1999 women without prior induced abortion and 1999 women with one abortion with the frequencies of low birth weight among infants born to women with two (n = 1850), three (n = 520), and four or more (n = 173) prior induced abortions.


RESULTS
After adjustment for confounding variables, we found no linear relationship in risk of low birth weight among women with one (relative risk [RR] = 1.2, 95% confidence interval [CI] = 0.9-1.5), two (RR = 1.5, 95% CI = 1.1-2.0), three (RR = 1.3, 95% CI = 0.8-1.9), or four or more (RR = 1.6, 95% CI = 0.9-2.9) prior induced abortions.


CONCLUSIONS
These findings confirm earlier reports of little or no evidence of harmful effects on birth weight by one or by two or more induced abortions. We further report that risk is not significantly elevated even in women with three, four, or more prior terminations of pregnancy when compared with women with one or two abortions.
Mandelson
M T
MT
Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA.
Maden
C B
CB
Daling
J R
JR
D000028:Abortion, Induced / Q000009:adverse effects* / Q000706:statistics & numerical data; D000328:Adult; D015986:Confounding Factors, Epidemiologic; D005260:Female; D006801:Humans; D015994:Incidence; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D016015:Logistic Models; D008393:Marriage / Q000706:statistics & numerical data; D008423:Maternal Age; D010298:Parity; D011159:Population Surveillance; D012307:Risk Factors; D014861:Washington / Q000453:epidemiology