Induced abortion and the chromosomal characteristics of subsequent miscarriages ( XXXX ).

@entity1 @entity2208 @entity2007 @entity5852
Data from a case-control study of miscarriages ( @entity2208 ) were used to test whether single and multiple induced @entity5852 are associated with @entity2208 in subsequent euploid (chromosomally normal) pregnancies. Cases and controls were identified in three New York City hospitals between April 1974 and November 1982. It was hypothesized that, if induced abortion increased the risk of subsequent @entity2208 , an association would be observed with euploid but not @entity2007 (chromosomally abnormal) @entity2208 . The frequencies of single and multiple induced @entity5852 among euploid cases and @entity2007 cases were compared with those among controls. Among both private and public @entity1 , the proportion of @entity1 reporting a single induced abortion was similar in euploid cases and in @entity2007 cases compared to controls. Among public @entity1 only, the proportions reporting multiple induced @entity5852 were also similar in euploid cases and in @entity2007 cases compared to controls (odds ratios = 0.9 and 1.0, respectively). In contrast, among private @entity1 , the proportion reporting multiple induced @entity5852 was raised among euploid cases (odds ratio = 2.2, 95% confidence interval = 1.3-3.7), although not among @entity2007 cases. This association was strongest when the first induced abortion was carried out before 1973, at a young age, or with a procedure other than suction curettage. In public @entity1 , the associations with @entity2208 did not vary with characteristics of the first induced abortion, but multiple induced abortion histories when the first two induced @entity5852 occurred before 1973 were in excess among euploid cases compared to controls. These results suggest that, for both private and public @entity1 , neither single nor multiple induced @entity5852 as now performed are likely to increase the risk of @entity2208 in subsequent pregnancies. They also suggest a mechanical origin for some miscarriages.
