Definitions

Gestational Age: the interval between the first day of the mother’s last normal menstrual period and the date of delivery. The category of gestational age is used to place the infant in one of three categories: preterm, term or post-term.

Live Birth: the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy, which, after such separation, breathes or shows other evidence of life.

Preterm: a gestational age less than 37 completed weeks (less than 259 days) of pregnancy
Preterm Birth Rate: the number of preterm births per 1000 live births in any given year.

Term: a gestational age of more than 37 completed weeks but less than 42 completed weeks (greater than 259 days, but less than 294 days) of pregnancy.

Post-Term: a gestational age of 42 or more completed weeks (greater than 294 days) of pregnancy
Post-Term Birth Rate: the number of post-term births per 1000 live births in any given year.

Birth Weight: the weight of an infant determined at birth, or shortly thereafter, expressed in grams (g). There are four categories of birth weight: normal birth weight, low birth weight, very low birth weight, and high birth weight.

Normal Birth Weight: a birth weight greater than or equal to 2500 g.

Low Birth Weight (LBW): a birth weight less than 2500 g.

Very Low Birth Weight (VLBW): a birth weight less than 1500 g.

High Birth Weight (HBW): a birth weight greater than 4000 g.

Small for Gestational Age (SGA)*: the number of live births whose birth weights are below the standard 10th percentile of birth weight for gestational age expressed as a proportion of all live births (in a given place and time).

Large for Gestational Age (LGA)*: the number of live births whose birth weights are above the standard 90th percentile of birth weight for gestational age expressed as a proportion of all live births (in a given place and time).

* SGA and LGA are relative measures, and vary substantially according to the standard used for their calculations.

Crude Birth Rate: the total number of births during a calendar year per 1000 population. The crude birth rate shows the impact of fertility on population growth.

Total Fertility Rate: the number of live births to women of all ages during a calendar year per 1000 population. The total fertility rate represents the number of children a women can expect t have in her lifetime. Births offset deaths when the total fertility rate approximates 2.1.

Infant Mortality: the death of an infant during the first year of life. There are four categories of infant death: neonatal death, early neonatal death, late neonatal death, and post-neonatal death.

Infant Morality Rate (IMR): the number of deaths of live-born babies in the first year of life per 1000 live births, in a given place and time. Stillbirths (also referred to as fetal deaths) are not included in infant mortality calculations.

Neonatal Death: the death of a child under 28 days of age.
Neonatal Death Rate: the number of neonatal deaths per 1000 live births.

Early Neonatal Death: the death of a child under 7 days of age (0-6 days).
Early Neonatal Death Rate: number of early neonatal deaths per 1000 live births.

Late Neonatal Death: the death of a child between 7 days of age and 28 days (7-27 days).
Late Neonatal Death Rate: the number of late neonatal deaths per 1000 live births.

Post-Neonatal Death: the death of a child from 28 days to less than one year of age (28-364 days).
Post-Neonatal Death Rate: the number of post-neonatal deaths per 1000 live births.

Perinatal Morality Rate: the number of stillbirths of 500 grams or more and early neonatal deaths per 1000 total births (live births plus stillbirths).

Fetal Death Rate: the number of stillbirths (500 grams or 20 weeks of gestation) per 1000 total births.

Stillbirth Rate: the number of stillbirths (500 grams or more) per 1000 total births of known weight.

Preconception Health: refers to the care of women of reproductive age (and their partners) before conception. This care utilizes interventions that aim to reduce behavioural and lifestyle risks to a woman's health or pregnancy outcome.

Perinatal: defines the period occurring around the time of birth, more specifically from 22 weeks (154 days) of gestation to 7 days after birth.