Stages of Development

Zygote was formed (trimester 1)

The zygote divides and multiplies, it continues to grow more and more. (trimester 1)

There are 100 cells by this time. (trimester 1)

There are billions of cells (trimester 1)

After the zygote divides, it travels down the fallopian tubes and implants itself in the lining of the uterus. (trimester 2)

Blood vessels grow, forming the placenta (trimester 2)

Basic structures of the embryo start to develop into areas that will become the head,chest, and the abdomen (trimester 2)

The neural tube forms along the back of the embryo which is developing into the spinal cord and the brain. (trimester 2)

The embryo is now called the fetus (trimester 3)

The sex organs begin to differentiate (trimester 3)

The fetus weighs around 1.4 pounds (trimester 3)

The fetus is almost ready to give birth (trimester 3)

The fetus is about now average weight and has very little room to move and birth becomes imminent (trimester 3)

The heart begins to beat and organs form and begin to function properly (trimester 2)

Article : Fetal development, what happens during the third trimester? Publisher : Mayo foundation for Medical Education and research Article ; Fetal development week by week Site : babycenter.org] Article : Stages of Pregnancy Site : my.clevelandclinic.org Article :The 1st trimester Site : mayoclinic.com