Difference between Gestational Age and Fetal Age

Many people get confused when talking about gestational and fetal age. Both these terms provide ways of measuring the development of a fetus during pregnancy and just before a child’s birth. Medical students and doctors across the world used these terms to determine the development of the fetus in mammals. It also helps the doctors find out if the development of the baby is satisfactory. Problems encountered during child birth and at the time of labour or delivery are mostly dealt with using the concepts of gestational and fetal age.

Both fetal and gestational age is expressed in days or weeks rather than minutes or seconds. Gestational age is almost always 14 days more than the fetal age. If you are studying medicine, you will be required to learn and understand the concept of fetal development and the tools available to measure the perfect growth of a child. It should be noted that calculation of one form of measurements can determine the other form easily.

Gestational age is defined as the measurement that determines the duration of pregnancy from the first day of most recent vaginal period. Fetal age on the other hand refers to the duration of pregnancy from the time of conception. Week by week signs of pregnancy can be medically checked using gestational age. Fetal age determines the fetal development and length of pregnancy if required.


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    Gestational age

    This form of measurements provides a way of determining the duration of pregnancy from the day of the last menstrual process. According to the concept of gestational age, the fetus requires at least 280 days or close to 42 weeks to fully develop in pregnancy. Depending on the time duration required for fetal development, the resulting pregnancy can be either premature or normal. If the gestational age is 37 weeks then the pregnancy is considered to be premature. Gestational age between 38 and 40 usually results in normal pregnancy.

    Depending on the needs of the mother, gestational age can be determined either before or after child’s birth. Ultrasound scans may be taken to measure the head and thigh bone size of the baby to calculate this measurement.

    - Image courtesy: kcravikumar.blogspot.com

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    Fetal age

    Fetal age is the measurement of the length of pregnancy from the time of conception. Women are more likely to conceive during the time of ovulation. Fertilisation must occur in the first 24 hours and therefore the signs of ovulation must be recorded accurately to correctly determine fetal age.

    - Image courtesy: topnews.ae

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