Association between percentage change in gestational weight and macrosomia in a diabetic maternal population
Authors: Chen Lei , Sun Ruixue , Wu Lifeng , Dai Kangwei , Ye Qianwen , Yan Shaorong , Lin Yuzhan 
Published: March 2024

Background
Numerous clinical studies have investigated the relationship between maternal gestational weight-related parameters and macrosomia in infants. However, research on the association between the percentage change in gestational weight and macrosomia in infants is lacking. Additionally, the existing clinical guidelines do not offer specific recommendations for gestational weight control in pregnant women with diabetes to prevent macrosomia deliveries.
Objective
This study aimed to investigate the relationship between the percentage change in gestational weight and macrosomia deliveries in pregnant women with diabetes.
Study Design:
This retrospective cohort study included routine obstetric examination and baseline clinical data of pregnant women with gestational diabetes mellitus who visited the Third Affiliated Hospital of Wenzhou Medical University between January 2019 and December 2020. The diagnosis of gestational diabetes mellitus was based on the criteria outlined by the International Association of Diabetes and Pregnancy Study Groups in 2010. The percentage change in gestational weight was calculated using the following formula: pre-delivery weight–pre-pregnancy weight) / pre-pregnancy weight. Macrosomia was defined as a birth weight greater than or equal to 4000 g. Continuous variables were analyzed using one-way analysis of variance or the Kruskal-Wallis rank-sum test, categorical variables were assessed using Fisher's exact probability test, and univariate analysis was used to evaluate the relationship between each variable and macrosomia deliveries.
Results
This study included 316 patients diagnosed with gestational diabetes mellitus, of whom 57 delivered infants diagnosed with macrosomia. In the unadjusted, partially, and fully adjusted models, a significant correlation was found between percentage change in gestational weight and macrosomia deliveries (odds ratio = 39.6, 95% confidence interval: 1.8-866.3, P = 0.019; odds ratio = 1344.9, 95% confidence interval: 35.4-51118.2, P < 0.001; odds ratio = 1139.7, 95% confidence interval: 0.9-1523385.0, P = 0.055), respectively. After adjusting for potential confounding factors (age, maternal place of birth, height, pre-pregnancy body mass index, history of macrosomia deliveries, fetal sex, pre-delivery hemoglobin A1c, pre-delivery triglycerides, pre-delivery apolipoprotein B, pre-delivery high-density lipoprotein, pre-delivery glucose, number of full-term deliveries, neonatal birth length, gestational age at delivery), a non-linear relationship was noted between the percentage change in gestational weight and macrosomia, with an inflection point at 0.18.
Conclusion
Results showed a strong correlation between the percentage change in gestational weight and macrosomia deliveries in our population of women with gestational diabetes mellitus; a non-linear relationship was found between the percentage change in gestational weight and macrosomia delivery. This result suggests a significant increase in the probability of macrosomia delivery when the change in gestational weight exceeds 18%.