Many clients are anxious to do the 4D scan early on in their pregnancy to confirm that there really is a “belly bean” in the tummy, that a heartbeat is present and to get confirmation on how far along they are.
We suggest coming in for an early scan at around 8-12 weeks of gestation as we want to ensure we can clearly see the baby transabdominally (on top of the belly). If you have irregular periods it is possible that your dates may be off and even a slight discrepancy in gestational age early on can mean that you are fewer weeks along making it difficult to clearly see an embryo with a beating heart.
Below is an example of a 9 week gestation in HD Live (Belly Bean or part 1 of the Watch Me Grow package). At this stage the baby measures about 2.5 cm from top to bottom (called the crown rump measurement) and has tiny legs and arms and often exhibits spontaneous twitches and stretches. Clear rhythmic heart pulsations are seen the chest.
Changes occur rapidly over the next several weeks and by 12 weeks more purposeful baby movements are evident and baby can open and close hands and wiggle and curl toes.
By 16 weeks your baby will take on a more typical baby-like appearance. At this stage grasping ability improves and baby may be able to hold hands. At this stage we usually can clearly see if the baby will be designated male or female at birth but can also avoid this area completely if you would prefer a surprise on the big day! Over the next several weeks your baby undergoes a big growth spurt and will more than double in weight.
At 24 weeks babies imaged in 4D start to appear fuller in the face and it is around this stage that we notice eyelids beginning to part and eyes open.
As the weeks progress the fetus continues to develop reserves of body fat and appears noticeably chubbier in the face by about 28 weeks. We are also able to clearly see expressions in 4D like grumpy frowns, mischievous smiles as well as sleepy yawns and hiccups.
Weight gain occurs quickly as baby progresses through the third trimester adding body fat that will help after birth.
We typically recommend coming in for your 4D scan by about 30 weeks (28 weeks if you have an anterior placenta) for singletons and 26 weeks if you are carrying twins. It is possible though to get great 4D images well after this stage providing there is an adequate amount of “space” or amniotic fluid around the baby which enhances image quality.
When Is The Best Time To Do A 3D/4D Ultrasound?