Gestational Age Vs. Fetal Age

Most pregnant women are confused about the terms 'gestational age' and 'fetal age'. You might be wondering whether these terms mean one and the same thing. The following information regarding 'gestational age vs. fetal age' will help clear all your doubts. The information provided below, might help you understand your ultra-sound reports and calculation of your due date.

Gestational Age

Gestational age is the time measured from the first day of your Last Menstrual Period (LMP) to the current date. It is usually expressed in weeks and you can cross-check week-by-week symptoms of pregnancy after knowing the gestational age. A full term pregnancy involves development of fetus over about 40 weeks (about 280 days). Childbirth during 38-40 weeks of pregnancy is considered as normal but a baby born before 37 weeks is considered as 'premature'. Human gestation period can be anywhere between 259 to 294 days. During pregnancy, doctors check whether the size of the head, abdomen, thigh bone, etc. is according to the gestational age. They do it with the help of ultra sound tests.

Fetal Age

The most fertile time to get pregnant is near ovulation. When the male sperm fertilizes the egg released by your ovaries, you can say that you have conceived. Ovaries release the female egg and the egg is available for fertilization only for 24 hours. If you have sex on that day, then the chances of getting pregnant are maximum. Fetal age is counted not from the date of last menstrual cycle but from the date of conception. In case you don't know the exact date of conception, doctors can estimate the date of conception from simple calculations. Normally, menstruation starts 14 days after ovulation. Ovulation and conception usually takes place in the middle of the menstrual cycle (if the cycle lasts for 28 days). So fetal age is obviously less than the gestational age.

Gestational Age Vs. Fetal Age

As explained above, fetal age is normally two weeks less than the gestational age. After the birth of the baby, assessment of weight, length, head circumference, skin and hair condition of the newborn baby helps decide the gestational age; which in turn helps determine whether the newborn baby needs any special care. Doctors can estimate the gestational age by checking the reflexes, muscle tone, posture and vital signs of the infant.

During pregnancy, knowing the gestational and fetal age helps determine the course of the treatment for the baby, especially in case of expected or potential problems. During prenatal checkups, development of the uterus and the fetus is monitored. Doctors need to know the gestational or fetal age to confirm that the development is perfect and there won't be any problem during childbirth. They can check the accuracy of the due date after knowing the gestational or fetal age. If they notice any symptoms of decreased fetal movement, they find out the cause and start the treatment immediately.

When gestational age is week 3, fetal age is week 1. For 7 weeks gestation, fetal age would be 5 weeks. On Internet, due date calculators, fetal/gestational age calculators are readily available. You just have to feed the date of your last menstrual period and average length of your cycle.

By calculating gestational as well as fetal age, you can check the accuracy of your due date. Mothers feel relaxed when they know that their baby is growing at the correct rate, the baby is gaining weight according to the established standards and the organs are developing at the right time.