The aims of this review are (i) to differentiate the adverse birth outcomes of pregnant women with type 1 (DM-1), type 2 (DM-2) and gestational diabetes mellitus (GDM) because these different types of DM were combined and/or confused frequently in previous studies, (ii) in the population-based Hungarian data to exclude the selection bias of the previously published hospital-based materials, and (iii) to check the efficacy of the recent special prenatal care of diabetic pregnant women introduced in Hungary during the 1980s in the prevention of adverse birth outcomes of diabetic pregnant women. Among adverse birth outcomes, the rate of preterm and postterm births, low and large birthweight of newborns, in addition the risk of structural birth defects, i.e. congenital abnormalities (CA) were estimated in the offspring of pregnant women with medically recorded DM-1, DM-2 and GDM compared the occurrence of different DM in pregnant women who had malformed fetuses/newborns (cases) and who delivered healthy babies (controls) in the population-based Hungarian Case-Control Surveillance System of Congenital Abnormalities, 1980-1996. In the case group including 22,843 offspring, there were 79 (0.35%) pregnant women with DM-1, 77 (0.34%) pregnant women with DM-2 and 120 (0.53%) pregnant women with GDM. The control group comprised of 38,151 newborns, 88 (0.23%), 141 (0.37%) and 229 (0.60%) had pregnant women with DM-1, DM-2 and GDM. The mean gestational age at delivery was shorter in the newborns of pregnant women with DM-1 while longer in the newborns of pregnant women with DM-2. The mean birth weight was largest in the newborns of pregnant women with GDM followed by DM-1, while the mean birth weight in the group of DM-2 did not differ from the reference value. On the contrary the rate of low birthweight was not lower in babies born to mothers with GDM, than in the reference sample, and the larger mean birth weight associated with the higher (the highest) rate of low birthweight newborns in the group of DM-1. The rate of large birthweight newborns was the highest in the group of GDM. Thus these data indicate a higher risk of both small and large birthweight newborns in DM-1 and a higher risk of large birthweight newborns in the group of GDM. The total rate of cases with CA was higher only in the group of DM-1 (adjusted OR with 95% CI: 1.5, 1.1-2.0) due to 4 specific types/groups: isolated renal a/dysgenesis, obstructive CA of urinary tract, cardiovascular CAs and multiple CAs mainly caudal dysplasia sequence which had a higher risk in the offspring of pregnant women with DM-1. However, the risk of total CAs was lower in the study compared to the risk of previous studies and the DM-1 related spectrum of isolated CAs was also different (e.g. there was no higher risk of neural-tube defects) and these findings indicate that certain part of maternal teratogenic effect of DM-1 is preventable with appropriate periconceptional and prenatal care of diabetic women including folic acid supplementation. There was no higher risk of total CA in the offspring of pregnant women with DM-2 and GDM. In conclusion the different type of DM associates with different fetotoxic and teratogenic risk for their offspring and the recent specific prenatal care of diabetic pregnant women seems to be more effective in the reduction of DM related isolated CA than other adverse birth outcomes because a higher rate of both intrauterine fetal retardation and large babies were found in the newborns of pregnant women with DM-1 whilelarge birthweight was recorded in the newborns of pregnant women with GDM. The major finding of our studies was that the recent special prenatal care of diabetic pregnant women including folic acid supplementation was able to reduce a significant part of maternal teratogenic effect of DM-1. Thus our study indicated first that folic acid supplementation is appropriate for the prevention of DM related isolated CAs.
|Title of host publication||Diabetes in Women|
|Publisher||Nova Science Publishers, Inc.|
|Number of pages||24|
|Publication status||Published - Dec 1 2011|
ASJC Scopus subject areas