An Early-customized Low Glycaemic-index (GI) Diet Prevents LGA Babies in Overweight/Obese Pregnant Women

High pre-pregnancy body mass index (BMI) and excessive gestational weight gain (GWG) are associated with many unfavourable maternal and neonatal outcomes.

Adherence to lifestyle recommendations could be a major determinant of the efficacy on preventing unfavorable outcomes, namely among overweight/obese women. Previous studies investigated adherence to specific dietary patterns and their effect on pregnancy outcomes; however, no study has investigated adherence among overweight/obese pregnant women and its effect on the onset of several maternal-neonatal outcomes.

This study aimed to determine whether the prescription of a lifestyle program, consisting of a customized low-glycemic index (GI) diet and a physical activity program, in overweight and obese women could affect the occurrence LGA babies. It also aimed to determine whether this kind of prescription influences the adherence to healthier eating habits, and how this, in turn, can influence the occurrence LGA.

High pre-pregnancy BMI and excessive GWG are associated with many unfavourable maternal and neonatal outcomes and are independent risk factors for gestational diabetes mellitus (GDM) and large for gestatiola age (LGA) babies. Overweight/obese women should be counselled regarding their body weight before conception; however, most women have access to obstetricians only when they are pregnant. The Institute of Medicine (IOM) revised the guidelines of recommended GWG according to the BMI; however, only a minority of women succeed in reaching the recommended GWG. Among the interventions aimed at preventing excessive GWG, few have demonstrated efficacy in high-risk populations; the principal issues are population heterogeneity, the interventional methods, and the timing of the interventional programs. Additionally, lifestyle interventions did not have a substantial effect on other clinical outcomes. Dietary advice to prevent gestational diabetes mellitus (GDM) appears to be beneficial in general, although the results are overly heterogeneous. A systematic review concerning exercise alone demonstrated no effect on preventing GDM, whereas another study showed only a slight protective effect. The reports evaluating the efficacy of diverse approaches (exercise, diet, lifestyle interventions, dietary supplements) to prevent GDM are of poor quality. Adherence to lifestyle recommendations could be a major determinant of their efficacy, specifically among overweight/obese women. Previous studies investigated adherence to specific dietary patterns and their effect on pregnancy outcomes; however, no study has investigated adherence among overweight/obese pregnant women and its effect on the onset of GDM. Nowadays, there are insufficient evidences for recommend a specific diet in preventing LGA babies.

This study aimed to determine whether the prescription of an early lifestyle program, consisting of a low-glycemic index (GI) caloric restriction and physical activity (PA), in overweight and obese women could affect the occurrence of LGA newborns. It also aimed to determine whether this kind of prescription influences the adherence to healthier eating habits, and how this, in turn, can influence the occurrence of LGA babies.

Eligibility Criteria:
Inclusion Criteria:

* age \>18 years
* singleton pregnancy
* BMI \>= 25 kg/m2

Exclusion Criteria:

* Chronic diseases including diabetes mellitus (first trimester glycosuria\> 100 mg/dl or fasting plasma glucose ≥126 mg/dL or random glycemia ≥ 200 mg/dL) and hypertension
* Previous GDM
* Medical conditions or dietary supplements that might affect the body weight (i.e., thyroid diseases)
* Previous bariatric surgery
* Smoking habits
* Contraindications to exercise
* Intent to deliver outside our hospital