IntroductionOptimal breastfeeding practices have far-reaching health and economic benefits. Evidence suggests disparities in breastfeeding practices by maternal age-groups, with younger mothers often having lower rates of breastfeeding initiation, continuation and exclusivity compared with older mothers. There is limited knowledge of trends and factors associated with breastfeeding practices, particularly among adolescent and younger mothers in Nigeria. We examine key breastfeeding practices in Nigeria over a 15-year period, comparing adolescent mothers to young women.MethodsWe used four Nigeria Demographic and Health Surveys collected between 2003 and 2018. We constructed six key breastfeeding indicators to cover the time period of breastfeeding from initiation to child age 24 months in women of three maternal age groups at the time of birth: young adolescents (<18 years), older adolescents (18–19.9 years) and young women (20–24.9 years). We used logistic regression to examine the association between maternal age group and select breastfeeding behaviours on the 2018 survey.ResultsAnalysis showed an increase in optimal breastfeeding practices across the four surveys and among all maternal age groups examined. Adolescent mothers had consistently lower prevalence for three of the six key breastfeeding indicators: early initiation of breastfeeding, exclusive breastfeeding <6 months and no prelacteal feed. Compared with young women, adolescent mothers had a higher prevalence of continued breastfeeding at 1 and 2 years. In multivariate analysis, we found that maternal age group was not associated with early breastfeeding initiation or with exclusive breastfeeding <6 months. However, several sociodemographic (ethnicity, region of residence) and healthcare-related (mode of delivery, antenatal care, postnatal breastfeeding counselling) factors were strongly associated with these two practices.ConclusionsIn Nigeria, there is need to better support breastfeeding and nutritional practices in adolescents and young women focusing on ethnic groups (Hausa, Fulani, Kanuri/Beriberi) and geographic regions (South East) that are lagging behind.