BIRTH

or Labour, in physiology, is the act by which a female of the cla Mammal i a brings one of her own species into the world. When the foetus has remained its due time in the womb, and is in a condition to carry on a separate existence, it is ex* traded from its place of confinement, in order to the life which belongs to its species, independently of the mother. The womb having reached its maximum of growth with the increasing size of the foetus, its peculiar irritability excites in it the power contraction; it thereby narrows the space within, and pushes out the mature foetus. The period gestation is very different in different animsds, but each particular specie it is fixed with much precision. In the womb the corporeal frame of man conmiences existence as an embryo; after further development, appears as a foetus; then as an immature, and finally a mature, child. With its growth and increasing size, the membranes which envelop it enlarge, womb also expanding to give room for it. At end of the thirty-ninth or the beginning of fortieth week, Hie child has reached its perfect state, and is capable of living separate from the mother hence follows in course its separation from her, is, the birth. Contractions of the womb gradually come which are called, from the painful sensations accompanying them, labour-pains. These are of two kinds first, the preliminary pangs, which begin the labour, do not last long, are not violent, and produce feeling of a disagreeable straining or pre ure. When the pregnant female is attacked by these, is often unable to move from her place till the is over, after which she is often free from pain some hours. Then follow the true labour-pains; these always last longer, return sooner, and are violent. The contractions of the womb take place in the same order as the enlargement had previously done, the upper part of it first contracting, while mouth of the womb enlarges, and grows thin, the vagina becomes loose and distensible. By means the fcetus, as the space within the womb gradually narrowed, descends with a turning motion towards the opening; the fluid contained in membranes enveloping the foetus, as the part making the greatest resistance, is forced out, and forms bladder, which contributes much to the gradu£tl large ment of the opening of the womb. It is therefore injurious to delivery, if hasty or ignorant wives break the membranes too soon. By repeated and violent throes the membranes at length burst, and discharge their contents, and some time the head of the child appears. As the skull-bones have not yet acquired their perfect form and stance, but are attached at the crown of the only by a strong membrane, and may be brought nearer together, the head, by the pre ure which undergoes, may be somewhat diminished in size, squeezed into a more oblong form, so as to through the opening of the matrix and the pelvis which it is contained, and, finally, through the ternal parts of generation; and when this is done, the rest of the body soon follows. The act of birth or delivery is accordingly, general, not an unnatural, dangerous, and diseased state of the system, as many timid women imagine. It is a natural proce of development, which more a disease than the cutting of the teeth, or coming on of puberty, although, like them, it give rise to important changes in the body, and various diseases. It is true that the proce of childbirth requires a violent exertion of nature, but is facilitated by many prej)arative8 and helps adapted to the i)urpose. If the birth succeeds in the descril>ed, it is called a, natural birth. For this retpiisite that the pelvis should be properly formdd, and that the opening should permit a free pa age to the perfect ftEtus; that the growth and size the fiptuH shuuld be proportioned to the pelvis, especially that the head should have the size designed live nature, proportioned to the diameter of the pelvis; also, that there should be a proper situation of the womb, in regard to the axis of the pelvis, and a proper position of the foetus, namely, the head down, of the back of the head in front, and towards the opening of the womb, so as to appear first at birth; and, of finally, that the external parts of generatipn should be in a natural state. in An easy birth takes place without any exce ive strainings, and in due season. A difficult birth proceeds naturally, but is joined with great efforts and pangs, and occupies a long time — over six or eight hours. The cause of it is sometimes the stiffne of the the fibres of the mother, her advanced yearn, the diithe proportionate size of the child's head, and various the other causes. Nature, however, finishes even these births; and women in labour ought not to be im-; mediately dejected and impatient, on account of that these difficulties. An unnatural (or properly an irregular) birth is one in which one or more of the on, above-mentioned requisites to a natural birth are wanting. An artijicial birth is that which is accomplished by the help of art, with in strum^its: or l^e hands of the attendant. Premature birth is the one which happens some weeks before the usual time, namely, after the seventii, and before the she end of the ninth month. Though nature has aspang signed the periixl of forty weeks for the full maturfor ing of the foetus, if sometimes attains, some weeks before this pmod has elapsed, such a growth that it more may be preserved alive, in some cases, after its separration from the mother. That it has not reached its mature state is determined by various indications. the Such a child, for instance, does not cry like full-grown and infants, but only utters a faint sound, sleeps con this stantly, and must be kept oonstantiy warm, otherwii»e is its hands and feet immediately become chilled. Be> sides this, in a premature child, more or leas, accord the ing as it is more or le premature, the skin over the whole body is red, often indeed blue, covered with a a fine, long, woolly hair, especially on the sides ol the face, and on the back; the fontanel of the head enis large, the skull-bones easily moved; the £aoe looks old and wrinkled; the eyes are generally mid closed; the nails on the fingers and toes short, tender, and soft, hardly a line in length; the weight of after such a child is under six, often under five pooodfi. The birth is called untimely when the foetus is separated from the womb before the seventh month. subhead Such children can be rarely kept alive; there are instances, however, of five months' children living. it A curious remark is found in good writers, that a and seven months' child is more likely to live than une bom a month later. pa in Laie birth is a birth after.the usual period of forty weeks. As this reckoning of the time of pregnancy exto birth is founded for the most part solely on the evidence of the mother, there is much room for mis in take or deception, llie question is one of much interest in medical jurisprudence, as the inquiry often arises whether a child bom mora than forty weeks is no after the death of the reputed father is to be con the sidered legitimate or not. The importance of the may question, and the uncertainty of the proof, have octo casioned a great variety of opinions among medical writers. Most of them doubt the truth of thtthis mother's a ertions about such a delayed birth, and give, as their roason, that natxire confines hen eriod of pregnancy; that grief, sickm-:^ it is ., cannot hinder the growth of the fa'tus, ^c Others maintain, on the contrary, that nature binds heraelf to no fixed rules; that various causes m^y of delay the growth of the child, . Abortion and miscarriage take place w*hen a f<rtiis by is brought forth so inuuature that it cannot U^e. They happen from the beginning of pregnancy to the seventh month, but most frequently in the third month. The occafiions, especially in those of a susceptible or sanguine temperament, are violent shocks of body or mind by blows, falling, dancing, cramp, pa ion, . 218