The folds or plicm also (fig. 442.), which, in infantile life, are distinguishable upon the anterior and posterior walls -of the cavity in the uterine body, resembling somewhat those in the cervical canal, gradually disappear ; their former situation being now indicated by only a slight groove or raphe in the median line, and one or two gentle elevations diverging towards either Fallopian tube. These traces in the cavity of the body of its original con struction out of two symmetrical halves, be corne generally lost after the uterus has been once impregnated, and indeed cannot always be distinctly seen in the nulliparous organ. One peculiarity in the form of the infantine uterus may be mentioned here, although it will be subsequently more particularly noticed. This consists in a curvature or inclination forwards of the upper part of the uterine body (fig. 467.). It is constantly more or less seen in infancy and childhood, and is usually partly retained in the virgin adult, but be comes lost after one or two pregnancies. In an excessive degree, it constitutes the con dition hereafter described as antiflexion of the uterus.
From the time of birth to puberty, the com ponent elements of the uterus remain nearly unchanged. They consist of granules and cells in various stages of development, from the round granular corpuscle to the elongated and ultimately fusiform fibre-cell ; the two latter being often drawn out, at their extremities, into long filiform threads. These are all imbedded in a semitransparent formless matrix, and dif fer in no respect from the corresponding tissues in the adult, except that they are go nerally softer and less tenacious in proportion as they are younger.
e. The uterus during n2enstrual The average duration of menstrual life is thirty years. It occupies usually the interval be tween the ages of fifteen and forty-five. The uterus in healthy women, throughout this en tire epoch, is maintained in a state of perfect aptitude for the reproductive office, being, so to speak, under the control of the ovaries, with which it manifests so direct a sympathy, that every periodic change in the condition of the latter is, so far as the present state of our knowledge justifies the assertion, represented by a corresponding preparatory change in the former. But the menstrual phenomena being reserved for subsequent notice, it- is only ne cessary to remark here that the uterus under goes usually a slight alteration in size about the time of eaeh eatamenial flow, when its tissues are opened up, and become more spongy from the larger afflux of blood to them.
The lining membrane appears to suffer a va riable amount of disintegration. In the uterus of women who have died during menstruation, the interior may present a slightly roughened appearance in certain places, or this may ex tend over the greater portion of the cavity. In women who menstruate painfully, it not infrequently happens that the entire uterine lining, to a greater or less depth, is exfoliated and discharged ; the process of expulsion being accompanied by much suffering and a greater escape of blood than occurs in ordi nary menstruation. These dysmenorrhceal
membranes (fig. 443.) present all the charac teristics of a true decidual structure, having upon their inner side, or that which had cor responded with the uterine cavity, the fine cribriform surface occasioned by the orifices of numerous utricular glands, and upon the re verse side the usual rough flocculent appear ance characteristic of the outer surface of membranes ordinarily discharged, along with the ovum, in abortion.
In other respects, the uterus, throughout menstrual life, exhibits little or no alteration in form or bulk, but continues to present those characteristics of constant aptitude for its greatest and most important office, which have been explained in the description already giveu of the adult organ ; and these characteristics, if no pregnancy intervenes, it preserves until the period arrives at which menstruation, to gether with the capacity' for procreation, finally ceases.
d. The uterus during gestation. The fully developed The gravid uterus is only another term for the fully developed uterus ; for, although the latter designation is com monly applied to the unimpregnated organ, when it has reached its ordinary size in the adult, the uterus does not attain the greatest amount of development of which it is nor mally susceptible until the terra of gestation is complete.
The case of the uterus is perhaps in certain respects sui generis ; for it is the case of an organ which, having reached a certain period of' growth, remains in a nearly passive con dition, so far as mere growth is concerned, until a further amount of development is evoked by a new stimulus. There are, in deed, two notable periods in the history of the development of the uterus, at which the in fluence of sueh an additional stimulus is per ceptible.
For, first, as already shown, the uterus, like the mamma, remains without any material change from birth to puberty. The establish ment of the latter condition is characterised by a correspondingly rapid evolution of both these organs. But the pubertal age !nay not arrive ; the individual may retain, in respect of reproductive capacity, the pre-pubertal con dition ; and the uterus, in these cases, does not proceed beyond its first stage of develop ment.* Again, the second stage, having. been reached at puberty, may be continued through men strual life, until, with the cessation of pro creative power, the period of natural decline in the organ commences, and this is the con dition which the part retains during the pe riods or intervals when it is not employed in the process of reproduction., as well as through out life in those cases in which it is never so employed. This degree of growth of the ute rus is evoked by the full development of the ovary and the commencing discharge of' ova, and is coexistent vvith the establishment of menstruation and the other conditions of pu berty.