Reproduction is complex, and many factors affect parents’ ability to make a baby, carry the baby to term, and deliver the baby without complications. These factors include age, genetics, income/education level, and many others.
Infant mortality is one type of birth outcome. Review the FAQs below for more information about infant mortality.
Infant mortality is the death of children under the age of one year. It is broken down into three types of mortality, defined by when the infant dies:
- Perinatal mortality. Perinatal mortality is the death of an infant after the 28th week of pregnancy but before the 7th day of life.
- Neonatal mortality. Neonatal mortality is the death of an infant that occurs after birth but before the 28th day of life.
- Postneonatal mortality. Postneonatal mortality is the death of an infant after 28 days of birth but before one year of age.
Live birth is the complete birth of a baby that must be breathing or showing other evidence of life, such as a heartbeat.
There are many risk factors for infant mortality, including:
- Birth defects (congenital abnormalities)
- Pre-term birth (birth before 37 weeks of pregnancy)
- Low birth weight (weight less than 5 lbs, 8 oz)
- Sudden Infant Death Syndrome (SIDS)
- Pregnancy complications
- Injuries (for example, suffocation)
Visit the CDC's Infant Mortality page to learn more about other risk factors.
The best way to prevent infant mortality is for mothers to be healthy before and during pregnancy. Access to good prenatal care (care before the baby is born) is important to ensure both mom and baby are healthy. Mothers should also avoid the behavioral risk factors outlined above, like stress, tobacco use, etc. Learn more about healthy pregnancy on the CDC's Pregnancy page.
Many environmental contaminants may be especially toxic in the womb. Many cross the placenta and make their way into the circulatory system of the developing fetus. Even if a potentially harmful exposure is identified, the health effects on the fetus are often not well understood until years later. Learn more about the infant mortality/environment connection on the CDC's Reproductive and Birth Outcomes page.
- Centers for Disease Control and Prevention – Infant Mortality
- Centers for Disease Control and Prevention - Reproductive and Birth Outcomes and the Environment
- Centers for Disease Control and Prevention – Maternal and Infant Health
- Centers for Disease Control and Prevention – SIDS Prevention for Parents and Caregivers