Objective To examine trends and projections of underweight (Body Mass Index, BMI < 18.5 kg/m 2 ) and overweight (BMI ≥ 25.0 kg/m 2 ) in women of reproductive age in 55 low-and middle-income countries (LMICs). Methods We used data from 2,337,855 women aged 15-49 years from nationally representative Demographic and Health Survey conducted between 1990 and 2018. Bayesian linear regression analyses were performed. Results During 1990-2018, the prevalence of underweight decreased in 35 countries and overweight increased in 50 countries. The highest underweight increase was in Morocco (5.5%) and overweight in Nepal (12.4%). In 2030, >20% of women in eight LMICs will be underweight, with Madagascar (36.8%), Senegal (32.2%), and Burundi (29.2%) projected to experience the highest burden of underweight. Whereas >50% of women in 22 LMICs are projected to be overweight, with Egypt (94.7%), Jordan (75.0%), and Pakistan (74.1%) projected to have the highest burden of overweight. 24 LMICs are projected to experience the double burden of malnutrition (both underweight and overweight >20%) in 2030. Noticeable variations in underweight and overweight were observed across wealth, residence, education, and age of women, with a higher rate of overweight in high-income, high-education, and urban women. These inequalities have widened in many countries and are projected to continue. The probability of eradicating overweight and underweight is nearly 0% for all countries by 2030, except Egypt is on track to eradicate underweight. Conclusions Although the prevalence of underweight declined, this decline has been superseded by the dramatic increase of overweight. None of the 55 LMICs is likely to eradicate malnutrition in women by 2030.