The help understand the importance of the first 2000 days of development the key messages have been divided into the Antenatal period (conception to birth), Brain development and Childhood experiences. The new ABC.
A Antenatal 
During pregnancy, a baby's health is being 'set' for the rest of thier life. The physical health of the mother and the lifestyle of a family impacts on the future health and development of the child.
B Brain development
During the first 2000 days the a child's brain grows rapidly and is shaped by their experiences, particularly the interactions they ahve with thier parents and other caregivers. What happens during this time has a lasting impact on development. Stressful events and experiences have been shown to influence future outcomes.
C Childhood experiences
Children need at least one sensitive, nurturing caregiver who can respond to their needs. Exposure to toxic stress such as domestic and family violence, untreated parental mental illness, substance misuse, financial and housing issues can have a negative effect. The greater number of stressors, the greater the risk to development.