Obstetric and Gynecological Nursing - The Carter Center

the ampullar portion. The functional life span of aspermatozoa
is about 48 hours / may be as long as 72 hours or longer.
Therefore, sexual coitus during this time may result in
fertilization /pregnancy.
3.2 Development of the Fertilized Ovum
After fertilization the ova passes through the fallopian tube
and reaches the uterus 3 or 4 days later. Division takes place
and the fertilized ovum divides into two cells, and then into
four, then eight, and sixteen and soon until a cluster of cells is
formed known as the morula.
These divisions occur quite slowly about once every 12 hours.
Next, fluid filled the cavity or blastocele appears in the morula
which now becomes known as the blastocyst.
Around the out side of the blastocyst there is a single layer of
cell known as the trophoblast while the remaining cells are
clumped together at one end forming the inner cell mass. The
trophoblast will form the placenta and chorion, while the inner
cell becomes the fetus, umbilical cord and the amnion.
Embedding of the blastocyst is normally completed by the 11 th
day after ovulation and the endometrium closes over it
completely.
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