Abstract: 【Abstract】 Objective To analyze demographic and clinical characteristics of infantile hemangioma （IH）, and to explore related risk factors for IH. Methods A multicenter case-control study was conducted. IH patients （case group） and healthy children （control group） were collected from West China Hospital of Sichuan University, West China Second University Hospital of Sichuan University and Yulin Community Central Hospital of Chengdu from October 2018 to December 2020. The data on patients′demographic characteristics, and risk factors during their mothers′ pre-pregnancy, pregnancy and perinatal period were collected and retrospectively analyzed. Univariate and multivariate analyses were performed using binary logistic regression. Results A total of 1 479 patients with IH and 1 086 healthy children were included in this study. There were 456 males and 1 023 females in the case group, with the age being 3.74 ± 2.82 months, and there were 359 males and 727 females in the control group, with the age being 3.95 ± 2.77 months. There was no significant difference in the gender ratio, age, ethnic composition, birth weight or birth height between the case group and control group （all P > 0.05）. IH lesions mostly affected the head and face （564 cases, 38.1%）, followed by the trunk （449 cases, 30.6%） and limbs （356 cases, 24.1%）. At the visit, 1 109 （75.0%） patients presented with proliferating IH, 1 059 （71.6%） with superficial IH, and 1 306 （88.3%） with focal IH. The IH lesion area ranged from 0.01 to 168.00 （6.24 ± 12.91） cm2, and the segmental IH area ranged from 7.50 to 168.00 （32.17 ± 26.94） cm2. Univariate logistic regression analysis showed some factors influencing the occurrence of IH （all P < 0.05）, including pre-pregnancy factors （delivery history and miscarriage history）, pregnancy factors （fetal distress, cord entanglement, history of threatened abortion, placenta previa, oligohydramnios, gestational hypothyroidism, gestational anemia, history of progesterone supplementation, history of thyroxine drug use, history of uterus myomas）, and perinatal factors （including fetal position, gestational weeks, premature rupture of membranes and preterm premature rupture of membranes）. Multivariate binary logistic regression adjusted analysis showed that fetal breech presentation, preterm birth, cord entanglement and history of thyroxine drug use during pregnancy did not influence the occurrence of IH （all P > 0.05）; the delivery history was the strongest independent risk factor for IH （adjusted OR = 5.624, 95% CI: 4.275 to 7.398, P < 0.001）, and gestational hypothyroidism and history of uterus myomas were protective factors for IH. Conclusions In this study, the average age of IH patients at visit was 4 months, skin lesions mostly occurred on the head and face, and most were superficial and focal in the proliferative stage. The occurrence and development of IH may be associated with placental diseases, hypoxia, maternal hormone levels during pregnancy, etc.

Key words: Hemangioma, Infant, Risk factors, Placenta diseases, Fetal hypoxia