Materials and Methods: This randomized controlled trial was conducted on 70 overweight and obese women (body mass index ≥25) within the age range of 18-35 years in the preconception period referred to health centers in Tabriz, Iran. Twenty-four-hour food records were completed by women for 3 days and participants" weights were measured before and 8 weeks after the intervention. Using a random block design and the allocation ratio of 1:1, the participants were divided into MI (6 sessions of training and MI) and control (routine preconception care) groups. The criterion for the primary outcome was the mean macronutrient intake 8 weeks after the intervention. All analyses were done according to intention to treat method.

Results: At the baseline, there was no statistically significant difference in terms of the mean of daily energy intake, carbohydrates, fat, protein, and weight (P > 0.05). After the intervention, the mean (standard deviation) of daily energy intake was 1841.3 (567.8 kcal) and 2131.0 (568.7 kcal) in intervention and control group, indicating a significant difference between the 2 groups with an adjusted mean difference (AMD) of -334.3 and a 95% confidence interval (CI) of -667.2 to -21.5 (P = 0.03). However, there was no difference between the 2 groups in terms of macronutrients (P > 0.05). After the intervention, the mean (SD) of participants" weight was 74.4 (6.94 kg) and 75.7 (7.82 kg) in intervention and control groups, which demonstrated a significant difference between the 2 groups (AMD = -1.30 kg, 95% CI = -2.09 to -0.51, P = 0.002).

Conclusions: MI is an efficient method of weight loss and the energy intake change can help preconception women with obesity or overweight to safeguard themselves against the adverse consequences of their pregnancy.