Therefore, the use in pregnancy is not recommended. Side effects
The nasal spray form of mometasone may cause the following side effects:

headache
Viral upper respiratory infections
sore throat
nose bleeds
cough
muscle and joint painSerious side effects include: Thrush (fungal infection in the nose or throat), slow wound healing, eye problems such as glaucoma or cataracts, weakened immune system (immunodeficiency) which causes an increased susceptibility to infections and adrenal insufficiency. The inhaled form of mometasone for asthma may cause the following side effects

headache
stuffy or runny nose
dry throat
swelling of nose, throat and sinuses
flu like symptoms
painful menstrual periodsSerious side effects may include: allergic reactions (anaphylaxis), increased risk of osteoporosis, glaucoma and cataracts, thrush in the mouth or throat, growth retardation in children, bronchospasms, adrenal insufficiency and weakened immune system which causes an increased susceptibility to infections. The topical (skin cream) version may cause:

burning and itching at the application site
acne
changes in skin color
dryness at application site
skin soresThe only serious side effect that is known with mometasone topical is adrenal insufficiency. Pharmacology
Pharmacodynamics
Mometasone furoate reduces inflammation by causing several effects:
Reversing the activation of inflammatory proteins
Activating the secretion of anti-inflammatory proteins
Stabilizing cell membranes
Decreasing the influx of inflammatory cellsIn addition to the glucocorticoid properties of mometasone furoate, it is a very potent agonist of the progesterone receptor as well as a partial agonist of the mineralocorticoid receptor. Mechanism of action
Mometasone, like other corticosteroids, possesses anti-inflammatory, antipruritic, and vasoconstrictive properties. For allergies, corticosteroids reduce the allergic reactions in various types of cells (mastocytes and eosinophils) that are responsible for allergic reactions.
The resulting ischemia (restriction in blood supply) and oxygen shortage, if left untreated for a sufficient period of time, can cause damage or kill heart muscle tissue (myocardium). Brain: Cerebral infarction is the ischemic kind of stroke due to a disturbance in the blood vessels supplying blood to the brain. It can be atherothrombotic or embolic. Stroke caused by cerebral infarction should be distinguished from two other kinds of stroke: cerebral hemorrhage and subarachnoid hemorrhage. Cerebral infarctions vary in their severity with one third of the cases resulting in death. In response to ischemia, the brain degenerates by the process of liquefactive necrosis. Lung: Pulmonary infarction or lung infarction
Spleen: Splenic infarction occurs when the splenic artery or one of its branches are occluded, for example by a blood clot. Although it can occur asymptomatically, the typical symptom is severe pain in the left upper quadrant of the abdomen, sometimes radiating to the left shoulder. Fever and chills develop in some cases. It has to be differentiated from other causes of acute abdomen. Limb: Limb infarction is an infarction of an arm or leg. Causes include arterial embolisms and skeletal muscle infarction as a rare complication of long standing, poorly controlled diabetes mellitus. A major presentation is painful thigh or leg swelling. Bone: Infarction of bone results in avascular necrosis. Without blood, the bone tissue dies and the bone collapses. If avascular necrosis involves the bones of a joint, it often leads to destruction of the joint articular surfaces (see osteochondritis dissecans).