The commonest cause the cause of a particular abortion is an abnormality of the fetus or chorion which is server enough to cause fetal death. Pregnancy will often continue in spirit of maternal disease , but any illness may cause abortion if it is sufficiently sever, especially acute fevers. In a few cases of rubella abortion occurs, but more often the infected fetus is born alive. Syphilis dose not early abortion, and it is an uncommon cause of late abortion; it is more likely to cause intrauterine fetal death after 28th week .
In diabetes the abortion rate is above average if the disease in not adequately controlled.
Uterine abnormalities.
The incidence of abortion is increased if the uterus is double or septate, but in much such cause pregnancy is uneventful.
Retroversion of the uterus a cause not a cause of miscarriage, except in rare instances in which the uterus become incarcerated and is left untreated.
A fibromyoma of the uterus which is closely related to the cavity of the uterus may cause abortion, but other fibromyoma will not do so.
Both thyroid deficiency and hyperthyroidism may be contributory causes of abortion.
Cytotoxic drugs or poisoning with lead may cause fetal death and abortion. An abortion is a miniature labour; the uterus contracts rhythmically, the cervix dilates
In some cases of incomplete abortion a piece of placental tissue may remain in the uterus
Clinical varieties of abortion
- Threatened abortion
- Inevitable abortion
- Complete abortion
- Incomplete abortion
- Missed abortion (carneous mole).
- Septic abortion
In threatened abortion there is bleeding into the choriodecidual space but not of sufficient extent to kill the embryo. Management
Routine scanning of patients with threatened abortion has shown that a common cause of bleeding in the first trimester is a twin pregnancy for the surviving twin is good.
If the abortion is complete the uterus is indistinguishable from a normal non-pregnant uterus.
Inevitable abortion
A threatened abortion become inevitable when the bleeding increases greatly and uterine contractions become rhythmic and strong. Inevitable abortion, entopic pregnancy and some cases of hydatiform mole all present with the triad of pain, vaginal bleeding and amenorrhea. Both entopic pregnancy and early abortion are associated with a short period of amenorrhoea followed by irregular uterine haemorrhage. In abortion the bleeding is usually bright red, often accompanied by clots, and is more profuse then in entopic gestation in which the bleeding tends to be dark red or brown .
In abortion the pain is not so sever and occurs after the onset of bleeding; it is intermittent like labour pains.
Management
The uterus usually expels its contents unaided. If the abortion is not quickly complete, or if haemorrhag become sever, the contents of the uterus are removed with a suction curette.
Complete abortion
On examination, pain is absent and bleeding is slight and decreasing. The uterus is smller
Management
Incomplete abortion
If there is still bleeding a week after an abortion which was thought to be complete it is in fact incomplete.
Management
Treatment is is directed to preventing infection, controlling bleeding and obtaining an empty and involuted uterus. If the bleeding is sever there may be shock. Even if the uterus is not empty, if the bleeding will often be reduced by the ergomenrine, although its action on the uterus is less early then in late pregnancy. The uterus remains bulky and the cervix is slightly dilated.
Septic abortion
There may be little bleeding or uterine contraction, and the cervical canal may remain closed. In other cases infection follows incomplete abortion, and the symptoms and signs vary in severity.
All cases are admitted to hospital. In case of incomplete septic abortion the treatment will partly depend on the amount of bleeding. Cases of clostridia infection require special mention. In all cases of septic abortion a careful watch is kept on the urinary output.
