after twin labour.
The dimensions depend upon the degree of
contraction. Under ordinary circumstances,
the entire length is 8 10 inches, and the
thickness of the parietes 1 inch. These first
changes in the dimensions of the organ, as
compared with the state previous to labour,
are effected solely by the contraction of the
uterine fibre. They consist chiefly in a re-
arrangement of relative position in the com-
ponent tissues, by which, while the entire
substance of the uterus remains undiminished,
its length and breadth are greatly reduced, and
the thickness of the parietes correspondingly
increased. In one respect, however, the en-
tire bulk* and weight are less than they were
before labour, because a much smaller quan-
tity of blood now circulates in the walls, but
the solids remain unaltered.
At the end of the first week, the diminution
of the organ is not very considerable. Its
weight is merely reduced from 1 Ib. 6 7 oz.
to lib. 3 4oz. At the end of the second
week, the rate of diminution is found to have
been much more rapid ; the organ now weighs
only 10 1 loz. At the end of the fifth week,
5 6oz.; and in the course of the second
month, it is reduced to its ordinary weight of
1 to 2oz. j but it never entirely regains the
UTERUS (DEVELOPMENT).
small size and dimensions characteristic of the
virgin state.
Metamorphosis and restoration of the com-
ponent tissues. The first and immediate re-
duction in size of the uterus, after parturition,
has been just stated to depend upon mere
contraction of the uterine fibre. But con-
traction alone will not account for those great
and remarkable reductions in the dimensions
of the organ which have been just described.
The true explanation of these phenomena is
furnished by a series of metamorphoses affect-
ing more or less the entire uterine tissues, by
which the greater portion of those structures
which have been formed during pregnancy,
become disintegrated and removed, while
other and new tissues are developed in their
place.*
In these metamorphoses, the colossal fibre
cells, which form the great bulk of the newly
added material, play the most important part.
These have been traced, during their develop-
ment in pregnancy, from the small fusiform
cell of the unimpregnated uterus to the fully
formed fibre of the organ at term. The growth
of these proceeds part passu with that of the
foatus, for whose expulsion they are destined ;
and this act being accomplished, their de-
struction and removal becomes a necessary
prelude to the recomposition of the entire
organ upon the same type as before impreg-
nation. In this respect, the aggregate forma-
tion of fibre cell is comparable to the deer's
horn, the placenta and other structures which,
having served the purpose of their formation,
and being incapable of suffering retrogression,
become caducous, with this difference, how-
ever, that the one class of structure being
thrown off in a mass, the act of separation is
striking and obvious ; while the deciduous
process in the other is gradual and fragmental,
and can only be discovered by the most pa-
tient and careful scrutiny.
The disintegration and removal of the ute-
rine muscular fibre is effected, first, by the
transformation of each fibre into molecular
fat. This process does not commence earlier
than the fourth or sixth day after labour, and
not later than the eighth day. Certain dif-
ferences are observable in the order of retro-
gression. Thus the process begins somewhat
later in the inner than in the outer lamina?,
while the cervix remains unchanged a few
days longer than the body. In the individual
fibres, the process of decay begins at many
points simultaneously. The fibres lose their
sinuous outline, and become paler; while
within them appear yellow oil granules,
commonly arranged in rows. The nucleus of
the fibre is pale, but distinct, until it becomes
obscured by the increase of the oil granules ;
while the extremities of the cells, on account
* On this subject the following ma}' be consulted
with advantage: Dr. R. Heschl, " Untersuchun-
gen iiber das Verhalten des menschlichen Uterus
nach der Geburt," in the Zeitschrift der kais. kon.
Gesellschaft der Aerzte zu Wien. 1852. B. ii.
p. 228. ; F. M. Kilian, " Die Structur des Uterus bei
Thieren," loc. cit. ; Schroeder van der Kolk, loc, cit.
659
of their tenuity, are the first to suffer disin-
tegration.
Fig. 455.
Process of involution or disintegration, and renewal of
the uterine fibre after parturition. (After Heschl.}
a, the old fibres filled with fat granulations
2 4 weeks after delivery; b, development of
new fibres in different stages, about the fourth
week.
During the second and third week, the
process of disintegration continues ; arid it is
probable that a considerable absorption of
effete material now takes place, since it is not
easy to explain otherwise that rapid diminu-
tion in bulk, especially in the second week,
which the entire organ undergoes, as shown
by the calculation of weights already given.
As a result of these molecular changes, the
uterus now loses its reddish colour, and be-
comes of a dirty yellow, and is at the same
time more easily lacerable.
In the course of the; fourth week, and pos-
sibly sometimes during the third, there ap-
pears, in the midst of the now degenerated
fibres, the first traces of a new formation of
uterine substance. These occur first in the
form of cell nuclei, which are concurrently
developed at several points ; and gradually,
while the last portions of the old muscular
coat are being disintegrated and absorbed,
acquire the character of the new muscular
fibre cells (fig. 455. b). So that, by the end
of the second month, the reconstruction of this
portion of the uterine substance is often com-
plete.
The disintegration of the remains of the
decidua, and the reconstruction of the lining
membrane of the uterus, which had been re-
moved during the act of birth, is effected by a
process very similar to that just described.
With regard, first, to that portion of the
inner uterine superficies, which had been co-
vered by the placenta, it is observed that this
undergoes a somewhat slow retrogression.
The veins, filled by thick clots in the normal
state in consequence of the progressive invo-
lution of the intermediate uterine substance,
occasion here a marked protrusion ; so that
very often, after four or six weeks, the pla-
cental space forms an elevated spot of twice
u u 2
660
UTERUS AND ITS APPENDAGES.
the circumference of a dollar. Finally, how-
ever, these coagula are removed, and, together
with the veins, disappear, while the place sinks
to the level of the surrounding parts ; and,
after becoming smooth and receiving an in-
vestment of mucous membrane, is generally
no longer discernible. The restoration of
the placental space to its former condition
does not, however, always proceed normally.
Sometimes, in consequence of excessive acti-
vity in the process of reconstruction, hyper-
trophic growths of the new material take
place ; so that, several months after labour, a
tumour of more or less considerable size,
formed at the expense of the uterine tissues,
is found to occupy the original seat of the
placenta. I have satisfied myself by several
microscopic examinations of the correctness
of Heschl's opinion, that in this way are
formed some of those anomalous-looking
fleshy substances which are occasionally dis-
charged from the uterus, and are regarded as
moles.
The hittological changes, which take place
after labour in the tissues lying internally to
the muscular coat, up to the complete resto-
ration of the mucous membrane, have been
examined by many observers, not always,
however, with corresponding results. It ap-
pears certain that a portion at least of that
layer of decidua which is still left attached to
the uterine walls, is removed by fatty trans-
formation, and that many of the products are
discharged by the lochia. Schroeder van der
Kolk has traced this process as it occurs in
the nuclear cells and fibres, which form so
large a portion of the decidua. Those very
broad fibre cells, which are visible in it up to
the ninth month of pregnancy, are no longer
to be found four or five days after labour,
when they appear to be transformed into long
cells, through an abundant fatty transforma-
tion which progressively continues, until, by
the increasing development of the oil granules
and the corresponding diminution of the cells
and fibres, the situation of the latter can ulti-
mately only be discovered by the still existing
longitudinal direction of the fat nuclei, while
all traces of a cell wall have entirely disap-
peared.
Without the aid of the microscope, how-
ever, it may be seen that, a few days after
labour, the entire inner surface of the uterus
is covered by a more or less red soft pulpy
substance, which has the same anatomical
composition as the decidua. This, which is
considered by some physiologists as identical
with the layer of decidua already described,
as formed, according to Kilian, Robin, and
others, as early as the fourth or fifth month
of gestation, is not discharged after labour,
but becomes the seat of that reparatory pro-
cess, by which the restoration of the mucous
membrane upon the uterine body is effected.
Between the twentieth and thirtieth day, this
layer begins to resume the character of a mu-
cous membrane. It is at first more pulpy, and
softer, and thicker than mucous membrane in
a normal state. The vessels become distinct
in it about the third week, and sometimes still
later. Previous to this, the blood appears to
be contained in simple channels between the
elongating cells.
The epithelium is as yet hardly formed.
By scraping the inner surface of the uterus
twenty days after labour, Schrceder found still
only the remains of half decomposed cells.
But no new cells with cilia could be yet with
certainty discovered.
The utricular glands make their appearance
last of all. In several cases, Heschl found
them completely formed at the end of the
second month ; but previous to this, their de-
velopment could not be traced.*
Finally, it may be said that the restoration
of the mucous membrane, with all its peculiar
structures, is completed about the sixtieth or
seventieth day after delivery, i. e. by the time
that the uterus is reduced to its normal bulk.
Thus it appears, that the act of involution
consists in two processes, which are concur-
rently performed, yet with opposite purposes.
For the act of reconstruction being com-
menced long before the retrograde metamor-
phosis is complete, the result of both is, that
a restitution or reconstruction of certain tis-
sues of the uterus, more or less complete,
takes place.
With regard to the muscular coat, it is
perhaps not any overstatement of the fact to
say that each ovum is provided with its own
series of fibres for the purpose of effecting its
expulsion, and that these, after parturition,
entirely disappear, or at least can no longer
be recognised, while a new series of embryo-
nic or undeveloped forms appears in their
place. The same may also be said of the
decidua, though with certain differences as to
the time and mode of its destruction and re-
novation. Regarding the fibrous tissue of the
uterus, little has been determined with accu-
racy ; but enough has been observed to ren-
der it probable that this also, to a certain
extent, becomes subject to fatty transforma-
tion. The blood-vessels appear to be likewise
partly involved in a similar process, although
their principal trunks probably suffer but little
change beyond a material diminution of size.
The peritoneum is that tissue which undergoes
the least apparent alteration. It preserves,
however, a thickness proportionate to the
reduced bulk of the organ, and consequently
it must suffer a corresponding involution.
Regarding the puerperal alterations in the
nervous system of the human uterus, but little
is known. Kilian-}-, after examining a spe-
cimen at eight, and another at twelve days
after labour, as well as the uterus of many
animals at different periods, arrived at no de-
finite conclusions. He thinks it in the highest
degree doubtful, that, in the puerperal state,
the nerve fibres undergo the same involution
process as the other tissues ; viz. that the
old fibres are entirely destroyed, and become
replaced by a new, younger, or embryonal
* By Kilian they are said to be formed during
pregnancy,
f Loc. cit.
UTERUS (DEVELOPMENT).
form. He rather conceives that a reduction
so takes place, that either the contents of the
nerve fibre are partly or entirely removed by
resorption, so that there remains, according
to circumstances, a partly or entirely empty
sheath ; or that the contents of the fibre are
transformed in the same manner that Gilnther
and Schon (Henle, Allgemeine Anat. p. 771.)
observed in divided nerves ; viz. that the
contents of the tubules become coagulated, as
after death, and are then subject to resorption:
the fibre appearing then to be perishing, and
ribbon-like, and the contents to be disappear-
ing. Regarding the human uterus, he thinks
it in the highest degree probable, that the
nerve fibre is included in the energetic resorp-
tion process that affects the puerperal uterus
generally ; that a reduction of the fibre fol-
lows ; and that, in the next pregnancy, it
again becomes developed pan passu with the
development of the other tissues.
/. The uterus after the menstrual epoch, and
661
in old age. Whether the uterus has been
employed, in its ultimate office, in the pro-
cess of reproduction, viz. that of gestation, or
whether it has proceeded only so far towards
this as to have been limited to the repetition,
in unvarying succession, of that preparatory
stage which is expressed by the minor func-
tion of menstruation, in either case the period
equally arrives at which the activity of the
organ passes away. Ova are no longer dis-
charged from the ovaries. These cease to be
creative or developing organs ; and with this
cessation of the proper function of the ovary,
there comes also a corresponding diminution,
and finally a termination of the correlative
offices of the uterus.
It is now interesting to observe how the
uterus gradually resumes some of the pecu-
liar features which it exhibited at an earlier
period of life.- It may be said to fall back
again into its infantine condition. For with
the shrivelling of the ovaries, and their reduc-
Fig. 456.
The uterus in old age; showing a return to the infantine proportions between die body and cervix.
o, the shrivelled ovaries.
This figure exhibits the parts of half the natural size. (Ad Nat.)
tion to a size as small sometimes as that of
a child of two or three years, (J%. 456.) the ute-
rus also gradually shrinks, not in all its parts,
but principally in the body, or that portion
which is chiefly employed in the processes of
menstruation and gestation. This part be-
comes atrophied more than the rest ; its
walls become thinner, partly from diminished
circulation in them, and partly from atrophy
of the component tissues, which appear pale
and nearly bloodless. Thus it happens that,
in advanced life, the walls of the uterine body,
no longer possessing that fulness which at an
earlier period caused them to encroach upon
thecavity,and to exhibit that incurvation of the
sides and fundus which has been described as
characteristic of the mature organ, again re-
turn to the straight and more attenuated con-
dition which they had in early life. We mav
often observe, therefore, in the uterus of aged
persons, a nearer approach to the form of
the equilateral triangle, caused by the short-
ening of the body and the straightening of its
walls, than is seen in the uterine cavity of mid-
life ; and it is this return to the form of the
foetal cavity, together with the now prepon-
derating size of the cervix, which remains
Fig. 457.
Thinning of the uterine walls in old age, and return to
the triangular form of the cavity characteristic of
the infantine (fig. 442.) and undeveloped uterus
(fig. 465). (Ad Nat. Half the natural size.]
nearly unchanged, that gives to the aged ute-
rus its greatest similitude to that of infancy
or early youth.
u u 3
662
UTERUS AND ITS APPENDAGES.
But these changes are not limited to the
body of the uterus. The external uterine
orifice being now no longer required to serve
as a conduit for fluids to or from the uterus,
or for the passage of more solid contents,
becomes reduced in diameter, and may some-
times be observed to possess an aperture
that would hardly admit the head of a mo-
derate sized probe.
Fig. 458.
Os uteri in old age. {Ad Nat.)
FUNCTIONS OF THE UTERUS.
The uterus, in common with the rest of
the generative organs, being concerned only
in the reproduction of the species, its offices
are limited to that period in which the
animal functions are maintained in their
highest state of efficiency. The growth of
the body is nearly or quite completed before
the sexual offices commence, and the power
of reproduction continues as long as the
frame is maintained in full vigour ; but when
the age arrives at which the animal func-
tions generally begin to decline, their de-
cay is anticipated by the total cessation of the
power of procreation in the female. The
period, therefore, is limited, yet not brief,
during which the functions of the uterus can
be exercised, and on either side of this epoch
the organ remains passive, except under ab-
normal states.
The chief functions of the uterus are those
which relate to 1. Menstruation; 2. In-
semination ; 3. Gestation ; 4. Parturition.
The office of the uterus in menstruation.
Although the uterus is the efficient instrument
in the performance of menstruation, yet the
power of initiating and regulating this function
resides in the ovaries, which exert a powerful
reflex influence, not only upon the uterus, but
also upon the entire organism. Without the
ovaries, menstruation has never been known
to occur. Their artificial removal is followed
by a permanent cessation of the catamenial
flow, although the uterus may be left unin-
jured ; while the congenital absence of both
ovaries is always accompanied by an enduring
amenorrhoea.
The external sign or evidence of menstrua-
tion consists in the occurrence of a sanguine-
ous discharge, which escapes from the vaginal
orifice of women in health, periodically, except
during pregnancy and lactation. This dis-
charge first appears usually between the four-
teenth and sixteenth years, and continues to
be repeated at intervals of a lunar month for
an average period of thirty years. The time,
however, of the commencement, as well as of
the decline, of menstruation is very variable,
and may be either much accelerated or re-
tarded, according to individual peculiarities.*
Periods of duration and recurrence. The
catamenial period and interval together occupy
a space of one lunar month. And in some
women this function is performed with such
regularity that the day, and very nearly the
hour, of its expected return may be predicted.
The natural duration of the flow varies from
three to five or even seven days. An interval
then occurs during which the flow entirely
ceases. This occupies from twenty-one to
twenty-five days; and it is during the first
half of this interval that conception most com-
monly takes place.
It cannot, however, be asserted that this
degree of regularity is observed even in the
majority of women. Frequently the period of
regular return is anticipated by one or more
days ; or, on the other hand, it may be re-
tarded, without the occurrence of any con-
comitant disturbance of other functions, such
as would justify the regarding of these ex-
amples as abnormal. But whatever may be
the amount of variation dependent in most
cases upon idiosyncrasy, still a law of pe-
riodicity is observed which, in all ages and
countries, has been recognised, and more or
less distinctly expressed by such terms as
catamenia, menses, courses, periods, regies,
mois, monatlicher Fluss, and the like.
No catamenial discharge takes place nor-
mally during pregnancy or lactation. Excep-
tions to both these rules, however, occur, and
instances of the latter are sufficiently common.
But with regard to the former, it is probable
that many at least of the recorded cases of
menstruation during pregnancy have been
cases in which the placenta was implanted
low down, or even over the os, under which
circumstances it is well known that slight
flooding will occasionally commence at an
early period of gestation, and observe a cer-
tain rough periodicity. Upon anatomical
grounds, a catamenial flux during pregnancy
can only be supposed possible where the con-
dition of the uterus is such as to admit of the
discharge taking place from the vaginal portion
of the cervix ; an occurrence which is shown
by Mr. Whitehead to have obtained in all the
instances of supposed menstruation during
pregnancy which he had investigated. For
" on examining these cases with the speculum
* For much valuable statistical information re-
lating to the periods of invasion and decline of the
catamenia, and in refutation of the popular belief
that these periods are greatly influenced by climate,
&c., see Robertson's Essays and Notes on the Pl^si-
ology and Diseases of Women ; also, on the subject
of menstruation generally, Whitehead, the Causes
and Treatment of Abortion and Sterility; A. Brierre
de Boismont, De la Menstruation, 1842 ; Raciborski,
De la Puberte', 1844.
UTERUS (FUNCTIONS).
during the existence of the menstrual pheno-
mena, the blood was invariably found issuing
from diseased surfaces situated upon or about
the labia uteri, none escaping from the interior
of the organ."*
But in any case there is wanting a sufficient
series of observations, taking cognisance of
the exact duration and times of recurrence of
such discharges, and comparing these with the
normal periods and intervals of menstruation,
to warrant an unhesitating belief in the occur-
rence of a true catamenial flow as a possible
phenomenon during gestation.
Quantity. The quantity of the menstrual
fluid which escapes at each period has been
so variously estimated at different times and
by different observers, as to render it obvious
that the calculations could not have pro-
ceeded upon any common data. Thus Hip-
pocrates, and afterwards Galen who quotes
him, states the quantity as two Attic hemina,
equal to about eighteen ounces. In recent
times it has been estimated by Magendie at
several pounds, and Haller gives the average
amount as varying from six to twelve ounces.
But all these estimates are too high. Dehaen,
who employed an ingenious method of mea-
surement, calculated that some women lost
three, others five ounces, and very few half a
pound ; but that it was exceedingly rare for a
woman who had no malady to lose as much
as ten ounces.f Probably the only proceed-
ing by which any definite result can be ob-
tained, is that of observing the rate of escape
of the discharge from the uterine orifice.
According to the observations of Mr. White-
head, this is generally so slow that no more
than from ten to twelve grains could be pro-
cured during the time that the patient was
able to endure the irksomeness of the pro-
ceeding. From these, and similar observations
of my own, as well as from other estimates, I
conclude that two to three ounces is probably
the full extent of the natural flow, and that a
discharge amounting to six or more ounces in
the aggregate will generally produce for the
time sensible effects upon the constitution,
such as general pallor, and some feebleness of
the muscular system.
Xature of the catamenial discharge. There
is no foundation for the belief once so preva-
lent, and even partially still retained, that the
menstrual fluid contains materials of a noxious
or poisonous nature, nor yet that it serves as
a vehicle for the depuration of the blood of
the female. The occasional fetid odour of
the discharge, and sometimes also of the
breath of women during menstruation, arises
from the decomposition of the fluid, as it
slowly collects in the vagina, and doubtless
also from its partial resorption into the system,
producing in such cases a heavy or foetid odour
of the breath, the cause of which was pointed
out more than two centuries ago by De Graaf. J
The menstrual fluid has always, even in health,