Pregnancy week 6 -The Beginning Of Eyes and Limbs 0
During pregnancy week 6, the gestational age is 5 weeks which means it would be between 36 and 42 days since the last menstruation. The embryonic age would be 3 weeks or between 22 and 28 days from date of fertilisation. At pregnancy week 6, the embryo begins to curve into a C shape and measures approximately 1/8 inch or 4 mm in length, though this can vary between 2 and 5 mm! The grooves that form the face and neck structures become evident – these are called branchial arches. Rudimentary ears – called the otic pits start to form and the heart develops further by bulging and beats with a rhythm, between 100 and 140 beats per minute. This may be picked up only on the ultrasound machine at this stage, but will become more audible within the next few weeks. Arm buds make an appearance along with a tail and the rudiments of the mouth form with the membrane rupturing at that point. Pregnancy week 6 will be indicated by the neural tube closing and the primordial lungs beginning to form, together with the future liver, gall bladder and pancreas. The urinary passage and the rectal passage separate, ureteric buds appear along with the spleen. Anterior and posterior horns in the spinal chord can now be differentiated quite clearly during pregnancy week 6. Dark spots form where the eyes and nose will eventually take shape.
