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Growth of the baby

28-30 weeks

Measuring growth

From 28 weeks of pregnancy the midwife will externally measure the length of your uterus. This way we can monitor its growth. The growth of the uterus is an indication for the growth of the baby. Apart from taking measurements, the midwife will also look at position of the uterus and the baby’s development. 

To get the most accurate measurements of the uterus, it is important that it is not measured by too many different midwives, preferably by two, but a maximum of three. This means that from 28 weeks two or three different midwives will be performing the checks. Unfortunately it will be more difficult to make appointments, because there is less choice of midwives. We hope you understand. But you can book your appointments a long time ahead if you prefer. There is no guarantee that the midwife performing your checks will be the same one assisting during the birth.

Birth weight

If a baby is born at exactly 40 weeks the average weight is around 3500-3600 grams. At 40 weeks, a weight between 3000 and 4000 grams is considered normal. So there is a large margin in what is considered a normal weight during the pregnancy and the birth.  If the baby is born before or after the due date, the weights can be different again.  

Growth ultrasound

Normally a growth ultrasound is only performed by indication. This means: if we believe your ‘bump’ is either too small or too big. You will have extra growth ultrasounds if you’ve had a small baby before.  During a growth ultrasound we measure the baby’s head, waist and thigh bone. These measurements will show if the baby is growing as expected. The growth check up can be repeated so that the baby’s development becomes as clear as possible, also known as a growth chart. We will also check on the amount of amniotic fluid. Growth ultrasounds usually take place between 22 and 40 weeks.

A growth ultrasound cannot determine the exact weight of the baby. During the last weeks of the pregnancy the measurements will be less accurate because the baby will now have curled up and/or the head has lowered into the birth canal. Sometimes the ultrasound makes the baby look smaller or bigger than average, but is actually the opposite.

You can choose to have a growth ultrasound at our practice without a medical indication; in this case your health insurance would not cover the cost. Please ask us about options.  

What if the growth ultrasound shows a small baby?

If the growth ultrasound shows an underdeveloped baby we will refer you to hospital. There may be a specific reason why the baby is small, for example a family history of small children. Depending on the reason, your referral may just be a one off appointment or you will remain under hospital care.

 If your baby is larger than average, we advise to have your blood sugar levels tested. We will provide you with a blood test form and further information about this test. Your blood will be tested for diabetes during pregnancy (gestational diabetes -GD). If there is no diabetes, then there are no further consequences to the pregnancy.

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