CONDITIONS AT CONCEPTION IN WOMEN WITH RECURRENT MISCARRIAGE

In order to evaluate the role of conditions at conception in the risk of miscarriage, we sent 234 women with at least two consecutive miscar riages after conceptions from the same partner a short questionnaire a sking for the birth dates of their mothers and their live or stillborn siblings and the occurrence of any maternal miscarriages. Complete in formation was provided by 186 respondents. Using matched logistic regr ession, we investigated whether these women were born more often than their siblings (total n=578) to young (less than or equal to 19 years) or relatively old (greater than or equal to 40 years) mothers or shor tly after a preceding pregnancy (born within 1 year). We also evaluate d whether they showed a different month-of-birth distribution. No incr eased odds ratios were found for young or advanced maternal age, or fo r short preceding birth intervals. However, relative to their siblings , cases showed a deviant month-of-birth distribution (p=0.08) with a p eak in (late) winter. These results indicate that low and high materna l age and short preceding birth intervals are not determinants of the risk of miscarriage in the daughter. They also suggest that there may be seasonally varying factors that prenatally influence the risk of mi scarriage.