Infanticide is a sub-group of infant mortality, in which an infant less than 1 year of age is a victim of homicide. Neonaticide is a sub-category of infanticide and although it has several different definitions in the literature, this paper will refer to neonaticide as being a homicide against a child that is 1 month of age or less. Post-neonaticide is another sub-category of infanticide, which is defined as homicide against a child that is over 1 month of age but less than 1 year of age.
Several factors contribute to infant mortality each year, and the most frequent are congenital anomalies, prematurity, cardiovascular/respiratory/infectious causes and injury . Injury can be sub-divided into unintentional and intentional. Among injury-related causes of death in infants less than 1 year of age, homicide has consistently been ranked as the 2nd leading cause of injury-related death in this age group .
A number of studies have analyzed various aspects of infant homicide, aspects of the act of homicide, perpetrator characteristics and victim characteristics. About 50% of infant homicides (less than 1 year of age) occur by the 4th month of life and 67% occur by the 6th month of life . Fujiwara et al. assessed homicides of children less than 2 years of age from 2001–2005 and categorized the causes of death as type 1 (beating/shaking injuries) and type 2 (all other homicides, including neonaticide). The study found that 75% of fatal injuries were type 1 injuries, the remainder being type 2 . Some studies have reported the common methods of homicide against newborns to be asphyxiation and drowning . However, other studies have found it difficult to classify causes of death based on death certificate documentation .
Regarding perpetrators, mothers are more likely to commit homicide in the first week of life, but after the first week of life, the perpetrator is equally likely to be a male or a female . Fuijwara et al, found that males were more likely to commit type 1 injuries (beating/shaking injuries, shooting), while women were more likely to commit type 2 injuries (drowning, poisoning, suffocation, strangulation, etc.) [3, 6]. Some investigators have also determined perpetrators are more likely to be young, unmarried, maternal lack of prenatal care, non-hospital birth, fewer years of formal education, Black or American Indian heritage [2, 8]. A study based out of Colorado found an additional association with unmarried status  and another out of Washington State observed an association with low income . Post-partum mental illness, in the form of post-partum depression or post-partum psychosis can be seen, with post-partum depression being much more common. Mothers with post-partum depression can have obsessional thoughts about them harming their child or checking impulses to ensure their baby is unharmed, however these mothers are less likely to harm their child. Mothers with post-partum psychosis who have delusions that their baby is evil are most likely significantly harm their child . By contrast, data on victim characteristics (the infant) are relatively sparse [2, 10, 11]. It is also noteworthy that most of available data on infanticide are more than a decade old and trends in the components of infanticide (i.e., neonaticide and post-neonaticide) remain unexplored. Accordingly, the aim of this study is to examine previous and most recent trends in infanticide and its components covering the period 2003–2017. Further, we examined selected characteristics and predictors of infanticides, neonaticide and post-neonaticide.
Infanticide is a public health issue and several strategies of prevention have been proposed and implemented in society in an effort to address infanticide.
One of those solutions is Safe Haven Laws, in which a parent can legally surrender an infant who might otherwise be abandoned.
Texas was the first state to implement this law in 1999 and by 2008 Safe Haven Laws were in effect in all 50 states. Wilson et al, found that most homicides occurred among infants that, at the time of death, were too old for Safe Haven relinquishment. [8
]. Another strategy has been earlier detection of post-partum depression and suicidal screening as 5% of mothers with young children also kill at least one of their kids. This can be done by asking depressed mothers what their plans would be for their children if they were to die, ask mothers about their thoughts and fears of harming their children. However, social stigmas and concerns that mothers will lose their children may prevent them from giving true responses [9
]. Still other strategies include pregnancy prevention, so as to prevent unwanted pregnancies, and improved prenatal care when pregnancy does occur. However, the role of sex education in schools remains a controversial issue with conflicting study results regarding the impact of sex education on pregnancy prevention. Additionally, there are many barriers to getting adequate prenatal care, such as depression, denial of pregnancy, financial barriers, transportation barriers, child care barriers, etc. [10