rule, cast off with the secretion and leave the body. If in
the course of its travel from the ovaries, through the tube to the womb,
the female ovum or egg meets with the male elements, fertilization or
impregnation may take place. If then it is not cast off it generally
lodges in the womb and pregnancy has begun. The male and female elements
are usually supposed to meet in the outer portion of the Fallopian tubes,
fertilization then taking place; but this can occur any place from the
ovary to the womb. When the fertilized egg enters the womb it is usually
arrested in the folds of the womb membrane nearest the opening of the tube
and at once attaches itself to the womb wall. The folds by which it is
surrounded then grow forward and their edges unite over the egg or ovum
forming a sac--the decidua reflexa. Then follows the development of this
ovum and with it the development of the womb, and this growth or
development constitutes the process which is called pregnancy.
The Embryo or impregnated egg is nourished in the womb by measures
preparing for it. The placenta or after-birth forms during the third month
of pregnancy. Its function is to furnish nourishment breathing
(respiration) and excreting power to the embryo or impregnated egg. The
fully developed after-birth is a roundish spongy mass with a diameter of
about eight inches and weighs about one pound. It is usually thickest at
the center, the edges thinning out to the membranes. The inner surface is
smooth and glistening and is covered by a membrane (amnion) and beneath
this two arteries and a vein branch in all directions.
The cord is attached to the inner surface of the after-birth and is of a
glistening white color, varying in thickness, and is about twenty-two
inches long, but it may be longer or shorter. It contains two arteries and
a vein, which run in a somewhat spinal course.
DEVELOPMENT AT DIFFERENT MONTHS.--
First month.--There are indications of the eyes, mouth and anus. The
extremities are rudimentary. The heart is 4/10 of an inch long.
Second month.--It is now about one inch long. The eyes, nose and ears can
be distinguished. External genitals. There are suggestions of the hands
and feet.
[516 MOTHERS' REMEDIES]
Third month.--The ovum is now the size of a goose-egg. Fingers and toes
separate, nails look like fine membranes. The neck separates the head from
the body. The sex can now be told. Length is five inches. Weight about 460
grains.
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