Chapter 3
The Pulse of a New Heart: Early First Trimester
(Brief excerpt of book chapter)
By the time a newly pregnant woman has missed her period, the rapidly dividing bundle of cells set into motion by fertilization has already become embedded within the lining of her uterus and begun the complex process of development.
There is an astonishingly rapid growth in the first few weeks after conception. Within about two weeks after a missed period (six weeks gestational age), the baby – the star of the show – first appears as a tiny oval blip approximately a tenth of an inch in length, with a regular flicker of her heartbeat visible on the screen, as seen on the ultrasound video below. Despite the baby's small size, the drama of the discovery is powerful for parents: For the first time, they are witness to the pulse of a new life inside the mother's body.
Between seven and eight weeks, considerable changes occur in the body shape and proportions, as the head develops a more rounded shape, the body elongates, and the neck straightens. You can see the difference in just one week between these two 3D images, the first at seven weeks and the second at eight weeks:
Growth is not the only activity going on during the first trimester. Complex systems are also developing to ensure that the baby receives all the necessary protection and nourishment to support this growth. These include the amniotic fluid, the placenta and the umbilical cord. Nutrients and oxygen travel through the umbilical cord from mother to baby. And going in the opposite direction, waste products go from baby to the mother's body for disposal. Here is a view of a nine-week baby attached to the umbilical cord:
