More than one million infants have been born using assisted reproductive technologies (ARTs) around the world. The proof and evidence indicate the prevalence of multiple pregnancies, low birth weight (LBW), prematurity, and congenital anomalies in them. This study aims to explore the baby's health in pregnancies resulting from assisted reproductive methods and natural pregnancies. The current research is a descriptive cross-sectional method. The sample volume of this study is 100 people of pregnant women who have given birth in Mahdiyeh hospital in Tehran; fifty of them are pregnant women who have been fertilized by ARTs, and others are naturally fertilized ones. The information was collected by SPSS software (version 22), evaluated by statistical tests, and considered a significant level (P<0.05
). The results showed that the LBW, infant mortality, intrauterine fetal demise (IUFD), intrauterine growth restriction (IUGR), placental abruption, placenta previa, birth weight, and Apgar score at 1 minute after birth does not have a significant relation with the age, occupation, marital duration, infertility cause, infertility duration of the mother as well as the history of the ART use and childbirth type. But there is a significant relationship between infant mortality and infertility duration, and most of the infant mortality is seen in mothers with an infertility duration of fewer than five years. Infertility and its treatment with ARTs may affect the baby's weight, so in this group of patients, it should be considered to take care of pregnancy duration accurately.