Survival of very low birth weight children and contributing factors: A study from Tehran, Iran

Birth of an infant with very low birth weight (VLBW) (weight less than 1500 grams) is a major cause of deaths and complications in infancy and childhood. Despite recent progressions in medical care and treatment for VLBW children, the mortality rate is high in this group of children. The present study was performed to better identify the survival rate of these children and the problems that affect the survival of this group of infants in the short and long term.

The study population was all infants weighing less than 1500 grams or infants who borne at less than 32 weeks of pregnancy. Infants whom birth occurred from the beginning to the end of 2018 in hospitals in Tehran were included. Information about these children was provided by the Family and Population Health Office of the Ministry of Health and Medical Education. Sampling was non-random and all information about the infants under study was recorded in a questionnaire. All data from the study were entered into SPSS-22 software and the results were presented using descriptive and analytical statistics. Survival analysis was performed by Kaplan-Meier test and the effect of variables on survival was evaluated using multivariate Cox model.

A total of 338 children were studied. Based on the results of cox regression models, the probability of one-month survival of children was about 68% and the probability of one-year survival was about 60%. Of the 10 variables affecting the survival of VLBW infants and children under study, 6 variables of maternal education, number of pregnancies, parent and infant insurance, gestational age, birth weight and maternal vaccination before pregnancy were significantly related with the death of infant (P ≤0.05).

The findings suggest one of the effective strategies for improving VLBW infant survival rate is encouraging women to continue their education, vaccinating mother before pregnancy, insuring family members and preventing multiple pregnancies.