Eight-week-old foetuses conceptual image. This could represent the baby boom of the 1950s or multiple births of IVF (in vitro fertilization). They are

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Eight-week-old foetuses conceptual image. This could represent the baby boom of the 1950s or multiple births of IVF (in vitro fertilization). They are attached to the placenta and the mother's blood circulation by an umbilical cord (left of each foetus). The sac surrounding the foetuses is known as an amniotic sac. The embryos' eyes and limbs are visible, as are their male sex. During the first trimester, embryos develop a distinct human appearance. In this early period, organ differentiation overshadows growth and all the major organs have been formed. At this age the embryo is about 4 centimetres in length and less than 10 grams in weight.

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Size: 3000px × 4200px
Photo credit: © DR M.A. ANSARY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -week-, amniotic, anatomy, baby, body, child, coloured, concept, conceptual, cord, developing, development, embryo, embryonic, fetus, foetal, foetus, foetuses, human, multiple, prenatal, reproduction, reproductive, sac, umbilical, unborn, weeks