These abnormal blood vessels may grow up from the plane of the retina and may bleed inside the eye. When the blood and abnormal vessels are reabsorbed, it may give rise to multiple band like membranes which can pull up the retina, causing detachment of the retina and eventually blindness before 6 months.Normally, maturation of the retina proceeds in utero, and at term, the medial portion (Nasal retina) of the retina is fully vascularized, while the lateral portion (Temporal retina) is only incompletely vascularized. The normal growth of the blood vessels is directed to relatively low-oxygen areas of the retina, but the vessels remain in the plane of the retina and do not grow into the vitreous humor. If excess oxygen is given, normal blood vessels degrade and cease to develop. When the excess oxygen environment is removed, the blood vessels rapidly begin forming again and grow into the vitreous humor of the eye from the retina.The key disease element in ROP is fibrovascular proliferation. This is growth of abnormal new vessels; this may regress, but frequently progresses. Associated with the growth of these new vessels is fibrous tissue (scar tissue) that may contract to cause retinal detachment. Multiple factors can determine whether the disease progresses, including overall health, birth weight, the stage of ROP at initial diagnosis, and the presence or absence of "plus disease". Supplemental oxygen exposure, while a risk factor, is not the main risk factor for development of this disease.
much of subSaharan Africa) ROP is rare as most premature babies do not have access to neonatal intensive care and so do not survive. Countries with moderate development indices are improving access to neonatal intensive care, and in these settings bigger, more mature babies are also at risk of severe ROP as neonatal care may be suboptimal. These findings have two main implications: firstly, much can be done in countries with moderate development indices to improve neonatal care, to reduce the risk of severe ROP in bigger babies and increase survival of extremely preterm infants, and secondly, in these settings bigger more mature babies need to be included in ROP programs and examined regularly so as to detect those babies developing ROP requiring treatment. In 2012, the World Health Organization published data on rates of preterm birth and the number of premature babies born in different regions of the world. This report contained three main findings: 

Premature birth has many different causes, and prevention is challenging,
Prematurity is the most common cause of neonatal death in many countries, totaling as many as 1 million infants annually due to complications of preterm birth, and
the number of preterm births is currently estimated to be 15 million, and increasing. History
This disease was first described in a premature baby in 1942 as reported by Theodore L. Terry. Between 1941 and 1953, over 12,000 babies worldwide were affected by it. Soul musician Stevie Wonder, actor Tom Sullivan, and jazz singer Diane Schuur are a few famous people who have the disease.