In 2006 12.8% of births in the U.S. were premature. Premature births are linked to delays in motor/neurologic function, intellectual and academic development, language problems, poorer executive functioning and worse behaviour. Premature births are more common in poorer people. Being poor also has an effect on child development and children who are both premature and have poor parents are at an even greater risk of developmental problems. A team of researchers from the University of Maryland and Pennsylvania State University looked into some of these problems in a study of 122 African-American women with premature babies. They found that psychosocial risk (mothers' depression, stress and self-efficacy) and sociodemographic risk (poverty, mothers' education and marital status) were linked to maternal sensitivity which in turn affected the strength of the attachment between the mothers and their children at 12 months. However, the health of the children did not affect maternal sensitivity or later attachment.
Candelaria, Margo, Teti, Douglas M. and Black, Maureen M. - Multi-risk infants: predicting attachment
security from sociodemographic, psychosocial, and health risk among African-American preterm infants Journal of Child Psychology and Psychiatry doi:10.1111/j.1469-7610.2011.02361.x