Changes in the uterine mucous membrane or in the placenta constitute another cause of hemorrhage. The turgescence of the mucosa, which is present from the moment at which the ovum reaches the uterus, is in it self a predisposing cause. During the third and fourth week the new utero-placenta vessels are so delicate that the slightest violence may sep arate them and cause bleeding. After the second month the vessels are still larger, so that an injury or a sudden increase of the blood-pressure may cause rupture of a vessel and extensive extravasation. When the blood is effused in large quantities, it either collects about the seat of rupture, until the hemorrhage gradually ceases, or it extends to the os and escapes from it profusely and for a longer or shorter period. Again, the blood infiltrates the placenta and undergoes secondary changes (pla cental apoplexy, or hEematoma.) The hemorrhage may be of a venous nature, induced by obstruction of the vena cava inferior.
The causes may be summarized as follows: menstrual congestion, ve nous stasis (from general or local causes), mental shocks, straining, di rect or indirect violence, imperfect development or attachment of the placenta, or separation of the same, inflammations or morbid growths of the uterus, acute febrile diseases, chronic toxic affections (syphilis, plum bism), the use of abortifacients, diseases of the foetus or placenta, and finally abortion. [To these causes should be added the distinctive factors, erosions of the external os, lacerations of the cervix, mucous polypi, tumors of the cervix, intemperate coitus.—Ed.
Diagnosis. —As soon as we have ascertained the cause of the hemorrhage, we have made the diagnosis. Erosion of the cervix is a very common cause of bleeding; it is usually confined to the posterior lip, and extends up the canal, and its origin is commonly referred to laceration of the cer vix from a previous confinement, whether it terminated spontaneously or artificially. The discharge from the eroded surface is often hemorrhagic, but as these erosions often cause abortion, the apparent may give place to real bleeding. The important point to decide is, when does a hemor rhage signify impending abortion, and when we are called to a case in which bleeding has continued for some time, does this bleeding result from a complete, or from an incomplete abortion? The treatment of these cases will be governed not only by our wish to preserve the ovum, but to guard the woman against both present and future harm- Abor tion does not necessarily follow hemorrhage, and every obstetrician has observed cases in which neither the mother, nor the child, was injured by long and profuse bleeding.
Treatment.—See chapter on Abortion.
II. Hemorrhage during the last Three Months of Pregnancy, and during Labor.—.4bnormal Insertion of the Placenta.
What is abnormal insertion of the placenta? Portal (1685) was the first to show that the placenta might be inserted in the inferior segment, and over the os, and this was confirmed by numerous subsequent writers; but Baudelocque (1824) was really the first one to affirm that the fundus uteri was its normal site. Authorities differ as to its exact insertion, Scan
zoni placing it on the right postero-lateral wall, Naegele and Siebold on the left, Credt and Spiegelberg at the right upper angle of the uterine cavity, Carmichael at the inferior part of the posterior wall. Hcgar affirms that it is attached most frequently to the posterior wall, and Gus serow (from 188 observations) adopts the same view, in which he is joined by Schroeder and Bidder. Hennig (651 cases) found the placenta inserted in the superior uterine segment in 11 per cent.
In order that its insertion may be abnormal, the placenta must not only be attached to the lower segment, but it must be near the os, or rather, must partially, or entirely, cover it. Several varieties exist, viz.: 1. The placenta is inserted completely over the cervix, so that the os is entirely covered (total or central placenta 2. The placenta is inserted at the lower segment, and over the cervix, so as to partially cover the os (partial). 3. It is inserted at the lower segment, so near to the cervix, that it slightly encroaches on it (marginal). Some authors (as Barnes) describe an intra-cervical insertion, which is rejected by Duncan and others. Marchal describes two varieties of " cervical pregnancy," one in which the ovum enters the cervix as soon as it reaches the uterus, and developes there, and the other in which the ovum developes in the cervi cal cavity, and, after it has reached a certain size, passes into the cavity of the uterus, and there continues its growth; in the latter case the ovum is attached to the fundus by a pedicle sufficiently long to allow it to enter the cervix. Various local disturbance, hemorrhage and abortion, usually result from this abnormal condition. Several cases of this nature have been reported (five well authenticated). Marchal concludes: secondary cervical pregnancy is admissible, the ovum being attached to the fundus by a long pedicle formed from the decidua serotina, which allows its growth to continue; but no case is on record in which a new placenta has been formed in the cervical cavity. Primary cervical pregnancy is doubt less extremely rare. Wenzel has even sought to prove that complete cen tral insertion of the placenta is impossible; it is certainly very rare, but well-authenticated cases have been reported. As a rule, only a portion (the smaller portion, according to Martin) of the placenta covers the os. Among 57 cases of this kind, it was inserted 44 times on the left and 19 times on the right side; among 84 cases of marginal implantation, it was 50 times on the right side and 34 on the left. Among 260 cases collected by various writers, 86 were examples of central and 165 of marginal inser tion. Muller's statistics, founded on 1411 cases, are different, showing 747 cases of central to 715 of marginal insertion, 31 of the women in the former and 59 in the latter case being primiparx.