Gestational Age

Gestational age relates to the age of an embryo or fetus (or newborn infant). There is some ambiguity as to how it is defined:

  • In embryology, the term "gestational age" is seldom used because it lacks precision. The timing of embryonic development starts with fertilization. In mammals, this proceeds through uterine implantation, until birth.
  • In human obstetrics, gestational age is often defined as the time elapsed since 14 days prior to fertilization. This is approximately the duration since the woman's last menstrual period (LMP) began. There is also a further distinction between the calendar gestational age described here, and the developmental gestational age determined by comparing an embryo or fetus to the average age of others that were at the same stage of development.

Unless the exact date of fertilization is known, counting from LMP has been the common method of computing gestational age. It involves the assumption that fertilization in humans typically occurs a consistent period (14 days) from the onset of the LMP. Although this "LMP method" of calculating gestational age is convenient, other methods are in use or have been proposed.

Read more about Gestational Age:  Methods, Accuracy, Classification, Uses

Other articles related to "gestational age, age":

Gestational Age - Uses - Postnatal Use
... Gestational age (as well as fertilization age) is sometimes used postnatally (after birth) to estimate various risk factors ... For example, it is a better predictor than postnatal age for risk of intraventricular hemorrhage in preterms treated with extracorporeal membrane oxygenation ...
Prenatal Development - Embryonic Period - Changes By Weeks of Gestation - Gestational Age Vs. Embryonic Age
... Gestational age is the time that has passed since the onset of the last menstruation, which generally or as standard occurs 2 weeks before the actual ... Embryonic age, in contrast measures the actual age of the embryo or fetus from the time of fertilization ... Thus, the first week of embryonic age is already week three counting with gestational age ...
Crown-rump Length - Measuring
... The measurement of CRL is useful in determining the gestational age (menstrual age starting from the first day of the last menstrual period) and thus the expected date of delivery (EDD) ... Different babies do grow at different rates and thus the gestational age is an approximation ... CRL growth (and thus the approximation of gestational age) may be influenced by maternal factors such as age, smoking, and folic acid intake ...
Large For Gestational Age
... Large for gestational age (LGA) is an indication of high prenatal growth rate, often defined as a weight (or length, or head circumference) that lies above the 90th percentile for that gestational age. 4000 grams (8 lb 13 oz) or 4500 grams (9 lb 15 oz) regardless of gestational age ...
Low Birth Weight - Causes - Being Small For Gestational Age
... Further information Small for gestational age Being small for gestational age can be constitutional, that is, without an underlying pathological cause ...

Famous quotes containing the word age:

    A great age of literature is perhaps always a great age of translations.
    Ezra Pound (1885–1972)