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Amniotic Sac

In today’s video you can clearly see the baby resting in the Amniotic Sac at about 11 weeks and even see its brain!

The amniotic sac is a pair of membranes (basically a filter that lets some things pass but stops others) where the baby is developing. The inner membrane is known as amnion, while the outer membrane is known as chorion. The amnion is filled with a fluid suitably called amniotic fluid which transfers essential substances such as oxygen from the umbilical cord to the baby. The chorion contains the amnion and is part of the placenta.

During labour, the amniotic sac breaks resulting in the ‘water breaking’ when the baby is ready to come out. In some cases, the amniotic sac doesn’t break during labour and the baby is born in a transparent bubble, this is quite rare and only happens in 1 in 80,000 cases- known as en caul birth!

At City Ultrasound, the amniotic sac is just one of the important structures we check at any scan from 8 weeks. On our website, we have in-depth information about our process and types of scans, but if you do have any questions at all, please feel free to get in touch with us!

amnion, amniotic sac, baby, fetus, pregnancy, scan, ultrasound