Introduction: There are several known risk factors for gestational diabetes mellitus (GDM), a condition associated with worse pregnancy outcomes. Once GDM is established, the association between the presence of GDM risk factors and pregnancy outcomes is less well-known. We studied the association between the number of GDM risk factors and pregnancy outcomes in a population of women with GDM.
Methods: Retrospective study of the Portuguese multicentre GDM registry from 2012 to 2017. We analysed only singleton liveborn pregnancies and excluded women with missing data on variables of interest. GDM risk factors were: first degree family history of type 2 diabetes mellitus (FHT2D), maternal age >40 years, body mass index (BMI) ≧30 kg/m2, previous history of GDM, and previous history of a macrosomic infant. Primary endpoints were pregnancy hypertensive disease (PHD) (pregnancy-induced hypertension or preeclampsia), preterm delivery, caesarean section, birth trauma, neonatal hypoglycaemia, and neonatal macrosomia. Women were grouped by number of GDM risk factors (none, 1, 2, 3 or more) and compared. A multivariate logistic regression analysis was built. Variables included were those with different distribution between groups and those known to be associated to the outcome under analysis.
Results and Conclusions: We studied 10 677 women with a mean age of 33±5 years, 529(5.0%) had >40 years, 2924(27.4%) had a BMI≧30 kg/m2, 4795(44.9%) had FHT2M, 1396(13.1%) had previous history of GDM, and 529(5.0%) had history of macrosomic infant. There was 3663 (34.3%) women with 0 GDM risk factors, 4309 (40.4%) with 1, 2106 (19.7%) with 2, and 599 (5.6%) with ≧3. Women with more risk factors more often gained excessive weight during pregnancy, were diagnosed in the first trimester, had higher HbA1c, and needed insulin more frequently. They more frequently had chronic hypertension, history of abortion, and were more often multiparous. The prevalence of PHD, caesarean section, and neonatal macrosomia increased with increased number of GDM risk factors. There were no differences between groups in preterm delivery, birth trauma or neonatal hypoglycaemia. After multivariate adjustment, women with 1, 2, and ≧3 risk factors had an OR (95%CI) of PHD compared to those without risk factors of 1.35(1.058-1.68), 1.76(1.37-2.26), and 1.74 (1.20-2.52), respectively. The OR for the association with caesarean section, were 1.19(1.08-1.31), 1.59(1.41-1.79), and 2.05(1.69-2.50), respectively, and for macrosomia 1.42(1.07-1.90), 2.12(1.56-2.90) and 4.58(3.18-6.60), respectively.Women with GDM with increasing number of GDM risk factors have higher risk of PHD, caesarean section, and neonatal macrosomia.
21 May 2022 - 24 May 2022