IMPAIRED GLUCOSE-TOLERANCE DURING PREGNANCY IS ASSOCIATED WITH INCREASED FETAL MORTALITY IN PRECEDING SIBS

Objectives. To analyze whether women with a diagnosis of gestational d iabetes in the current pregnancy had an increased rate of stillbirths or of large for gestational age infants in previous pregnancies withou t an overtly present/diagnosed gestational diabetes. Design. A case-co ntrol analysis with two controls for each case, matched for year of de livery, maternal age (5 year class), and parity. Material and Methods. All women with a diagnosis of gestational diabetes and delivered betw een 1987 and 1992 were identified from the Swedish Medical Birth Regis try For each woman, the first delivery with that diagnosis was used as proband case (n=3,958). To each case and control, all previous sibs s ince 1973 were identified. Comparisons were made between cases and con trols but also between sibs of cases and sibs of controls. Results. No significant difference was found in stillbirth rate between cases and controls (OR 1.33, CL 0.64;2.77). The rate of intrauterine deaths was significantly increased among previous sibs of the cases compared wit h the sibs of the controls: after stratification for year of birth, ma ternal age and parity an odds ratio of 1.56 (95% CL 1.12;2.19) was fou nd. Infants born of women with gestational diabetes were heavier (mean 145 g, 95% CL 123;168 g). Similar differences were seen between immed iately previous sibs of cases and controls (mean 155g, 95% CL 127;183 g). Conclusions. The figures indicate that in pregnancies before a del ivery with gestational diabetes the perinatal prognosis was significan tly poorer than expected which could be due to the presence of undiagn osed and untreated gestational diabetes. The results argue for an impr oved screening for gestational diabetes during pregnancy.