By Emma Innes PUBLISHED: 07:59 EST, 3 January 2014 | UPDATED: 12:12 EST, 3 January 2014 A baby girl has undergone a life-saving procedure while still partially inside her mother's womb. Doctors feared a rare condition meant Sienna Smith would not be able to breathe when she was born, so conducted the emergency procedure before her birth. A team of 20 medics were involved in the two-hour operation. Sienna Smith (pictured with her parents, Sarah-Jane Harrup and Deryck Smith) had to have a life-saving procedure before she was born because a swelling on her neck could have prevented her breathing
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Sienna Smith was found to have a swelling on her neck during a scan
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Medics feared it would squash her windpipe, stopping her breathing at birth
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They performed a Caesarean section but before fully removing her from the womb and cutting the umbilical cord, they inserted a breathing tube
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After her birth, the swelling subsided, allowing her to breathe normally
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Instead of being a tumour, as doctors had feared, the swelling turned out to be a goitre - an enlarged thyroid gland
After opening Ms @placeholder’s stomach, they lifted Sienna's head so a tube could be inserted into her throat.