Red bumps on the body of a pregnant woman of four months may be due to pregnancy itchy rash, eczema, hives and other conditions. 1. pregnancy itchy rash: the cause of the disease is not clear, mostly considered with pregnant women blood estrogen content is too high, cholestasis and other conditions. Some patients also have a history of atopic dermatitis and family history. Early-onset pregnancy itchy rash usually occurs in the third to fourth month of pregnancy, scattered and symmetrically distributed round papules, preferably on the trunk and upper arms and femurs, which can be normal skin color, reddish color, and so on. The patient will also be accompanied by intense itching, after the condition improves, but also residual temporary hyperpigmentation. 2. Eczema: the cause of the disease is still unclear, mostly considered to be related to heredity, endocrine and metabolic diseases, immunogenetic, female hormone level changes and other factors. Patients often appear chestnut-sized papules, papules, blisters, etc., and can also be accompanied by redness, swelling, oozing and other conditions, which can also appear pregnant women four months of the phenomenon of red bumps on the body. 3. Urticaria: usually associated with food and drug allergies, physical stimulation, mental stress, chronic hidden infections, autoimmune and chronic diseases. The patient will often appear to wind, angioedema and so on, some patients can also appear itching, erythema and so on, which can also be manifested as a pregnant woman four months on the body long red bumps. It is recommended that when a pregnant woman is four months old and has symptoms of red bumps on her body, she should make a clear diagnosis in time and strictly follow the doctor’s instructions for treatment.