Hyperemesis Gravidarum, the Pernicious Vomiting of Pregnancy, is commonly classified among the toxemias; but as the etiology is not known definitely, this classification is one of convenience more than exactness. Nausea and vomiting occur so frequently in the early months of gestation that they are deemed almost physiological, but when these symptoms become very grave and persistent they are undoubtedly pathologic, and are said to be pernicious, as they may lead to abortion, or to the death of the woman. In 1813, Simmond first successfully employed artificial abortion to save the woman in this condition, and thus added a possible moral quality to the disease. Therapeutic abortion was used in 1608, and Soranus of Ephesus, in the second century, mentions it.

The pernicious nausea commonly begins in the second month of pregnancy, less frequently in the fourth month, but it may be delayed until the sixth month; if it occurs after the sixth month it is, almost as a rule, an evidence of nephritis. It may last from about a month and a half to three months, but in toxemic cases it may result in death in two weeks. Sometimes remissions occur.

In 1852, Paul Dubois described the disease, and his division into three stages is still used in articles on pernicious vomiting, although these stages are not clearly marked clinically. In the early months of gestation the stomach may become unable to retain food, and there is notable loss of appetite; the condition is then grave. There may be retching at the sight of food, at any change of position, or at the entrance of a person into the room. The emesis may recur so often at night as to cause exhaustion from insomnia. Hiccough, thirst, pain in the stomach, and soreness of the thoracic muscles are frequent and troublesome symptoms. In some cases there is salivation.

The vomitus is food, mucus, and some bile at first; later mucus and bile; finally it contains blood. The blood may come from the mouth, pharynx, or stomach, and it is serious if it is gastric. The urine is scanty, and shows nephritic irritation. At times it contains blood, bile, acetone, diacetic acid, indican, and rarely sugar.

In the second stage of the disease all symptoms are aggravated, and the stomach will not retain anything. There is extreme thirst; the patient faints often, and loses weight rapidly. In chronic cases there is much emaciation. The mouth is like that in a case of typhoid. Sometimes there is a low fever; again, the temperature is subnormal, with a rise before death. The pulse is rapid and weak, and the post-mortem heart shows fatty degeneration as in a fatal sepsis.

In the third stage the mind is affected, there is delirium, stupor, and coma; the vomiting ceases, the pulse grows more rapid and feebler, and the weakness becomes more and more overwhelming until the patient dies. This third stage is commonly short. In these conditions it is too late to empty the uterus, and any attempt to do so then only hastens death.

In some cases the fetus is apparently not affected; in toxic cases it is affected, and then there may be miscarriage. If the fetus dies the vomiting ceases, as a rule.

The liver enlarges in the first stage and later diminishes. There may be a general hemorrhagic hepatitis and acute yellow atrophy, or partial fatty degeneration around the central lobular veins. Necrosis also occurs. Acute parenchymatous nephritis and hemorrhages into the kidneys are often observed.

Neurotic and hysteric women are more liable to this disease than the nervously stable. There is a direct communication by the sympathetic and vagus nerves between the stomach and the uterus and its adnexa, and thus reflex irritations readily pass to the stomach. Through this path vomiting is caused by any unusual distention of the uterus, as when the fetus grows too rapidly; or when the size of the ovum is larger than normal, as in twin pregnancies; or in irritations like hydramnios, displacement of the uterus, acute anteversions, retroversions, or flexions which pinch and stretch the nerves. Inflammations, as metritis, endrometritis, and cervicitis; tumors of the uterus; diseases of the adnexa or of the pelvic connective tissue or peritoneum are other sources of reflex vomiting. The proof that such are causes is that the vomit ceases when the conditions mentioned are cured. Such conditions exist, however, in women who are not pregnant without causing vomit; there is therefore some special disposition in the pregnant.

Diseases which in themselves have vomiting as a symptom will in pregnancy make the vomit pernicious. Such are chronic gastritis, gastric ulcer, enteritis, cancer, helminthiasis, large fecal concretions, enteroptosis, tubercular peritonitis, and gall-stones. What is apparently pernicious vomiting in pregnancy may be the beginning of acute miliary tuberculosis. Diseases of the air passages—hypertrophied turbinates, septal spurs, laryngeal and apical tuberculosis—seem to cause the vomiting or to dispose to it. When vomit is associated with uremia, this occurs, as a rule, in the last months of pregnancy.

The cause, again, may be in the nervous system, from either a demonstrable lesion or a functional imbalance—paresis, locomotor ataxia, tumors or tubercle of the brain, meningitis, polyneuritis. Even when the nervous system is not directly the cause of the emesis, the remote irritant may work through the nervous system. A bad neurotic inheritance, as from alcoholic, insane, or weak parents, disposes to neurotic hyperemesis.

Toxins from the fetal syncytium appear to be another cause of the vomit. The syncytium is a mass of protoplasm without cell demarkation but with nuclei scattered throughout the substance. Sometimes this embryological cellular material starts to grow after the manner of a cancer, and then it is very malignant (syncytioma malignum), but its connection with the pernicious vomit of pregnancy is more theoretical than established. In physiological conditions the toxins in the blood are neutralized by the secretions of the ductless glands of the body, and in pregnancy probably these same glands by intensified activity effect the same result. Injection of blood serum taken from healthy pregnant women has cured cases of toxemic pernicious vomit, and this makes the theory much more probable.

To diagnose the etiology of pernicious vomiting is not always easy. We must decide first whether the emesis is really pernicious or not; secondly, we have to determine whether or not it is due to the presence of the fetus; thirdly, we are to differentiate the primary and adjuvant causes for intelligent treatment. The age of the fetus must be known to determine whether we may licitly interfere so as to remove the fetus from the uterus if necessary, in medical opinion, to do so.

Trousseau emptied the uterus of a woman to stop her pernicious vomit, but she died, and at the autopsy he found a cancer of the stomach. Caseaux discovered tubercular peritonitis in a woman who had died after a diagnosis of hyperemesis gravidarum; Beau, tubercular meningitis in a like case. Williams of Johns Hopkins University stopped a very grave case of pernicious vomiting in a neurotic woman merely by telling her of the dangers of artificial abortion.

There is no settled mortality percentage in hyperemesis gravidarum because so much depends on diagnosis and treatment. Braun, in 150,000 obstetrical cases, never had a death from pernicious vomit; others have a mortality of 40 per cent.

The treatment is technical, and is given in detail in books like De Lee's Principles and Practice of Obstetrics.[136] Suggestion and the environment are important elements in the treatment. Local anesthetics, mechanical drugs like cerium oxalate and bismuth, depressomotors, external applications, and gastric lavage are indicated in the early stages of the disease, but are rather harmful than useful in later stages. Adrenalin, ten drops of a 1:1000 solution by mouth, or three drops hypodermically as doses, often cures. Sergent and Lian reported six such cases in one paper in 1913. Hypodermic injection of the extract of corpus luteum in 1 c.c. doses has been effective in some cases. So has the injection of defibrinated serum from a healthy pregnant woman. Curtis describes the technic in the Journal of the American Medical Association, February 28, 1914. The gynecologist must adjust uterine displacements and heal cervical erosions. The oculist, laryngologist, and otologist are to remedy refractive errors and remove irritants in the air passages and the ear.

The treatment of last resort is to empty the uterus. This will cure all cases of neurotic and reflex origin if done early enough. In these cases, if the therapeutic abortion is deferred until very late, the patient will die of exhaustion. Toxemic cases do not react well after therapeutic abortion because of the damage previously done by the circulating poison, especially in the liver. A positive diagnosis of toxemia cannot always be made, and many patients in whom the diagnosis has been made correctly recover without abortion. Apart from moral considerations, it is very difficult to determine the proper time to empty the uterus. A test is made of the glycolytic power of the liver by giving two ounces of levulose internally; and if sugar shows in the urine, this means that the liver is unable to act normally, that it has been attacked and disabled by the toxin, and therefore the therapeutic abortion should be done. Again, a marked concentration of the blood, shown by erythrocytosis and leucocytosis, indicates starvation. Some obstetricians perform abortion when the pulse remains above 100, at the appearance of fever, blood from the stomach, jaundice, albuminuria, mellituria, acetonuria, indicanuria, or marked loss of weight. Polyneuritis, with icterus and bile in the urine, is another indication for abortion; a patient may die from polyneuritis alone after the hyperemesis has ceased. Not one but all these facts must be considered, together with one's own clinical experience.

In hyperemesis gravidarum, as elsewhere, therapeutic abortion is never permissible, under any circumstances, if the child is not viable. If the mother cannot be saved without emptying the uterus, the mother must die; there is no way out of the difficulty. The proof that this doctrine is correct has been given in the introductory chapter on Homicide and when considering abortion in general.