The Prevalence and Etiology of Ophthalmia Neonatorum among Hospital-Born Babies in Tehran, Iran

Background: To determine the prevalence rate of ophthalmia neonatorum and its bacterial and chlamydial causes among hospital-born babies in three medical centers in Tehran, during 2001–2002.
Materials and Methods: This descriptive study was performed on 3140 hospital-born babies including 1699 male and 1441 female subjects. All newborns were examined and followed up to the age 30 days after discharge for the signs of conjunctivitis. In the cases of ophthalmia neonatorum, the bacterial etiology was verified by examination of smears and cultures of ophthalmic exudates and Chlamydia Tracomatis was verified by direct immunofluorescent (DIF) microscopy. 
Results: There were 170 cases of ophthalmia neonatorum (5.4%). Exudate smears were positive for Gram positive cocci in 20.6%, Gram –ive bacilli in 8.8%, and Gram negative cocci in 1.8% and were negative in 68.8%. The most frequent microorganisms found based on cultures were: coagulaseive staphylococci (15.3%), Staphylococcus epidermidis (13.5%), E. coli (7.6%), and Staphylococcus aureus (5.9%), but there was no growth in 48.2% of the cultures. DIF samples were positive for Chlamydia trachomatis in 10 cases (5.9%). Most of the affected babies were male (62.4%) and more than 75% were born through normal vaginal delivery (NVD). Premature rupture of membranes (PROM) was the most common maternal precipitating factor (10%).
Conclusion: The prevalence rate of ophthalmia neonatorum among hospital-born babies in Tehran is considerable and neonates born to mothers with PROM through NVD, especially the male newborns should be carefully observed for development of ophthalmia neonatorum.