If you have a cough in the fourth month of pregnancy, if the cough is not particularly serious, you can first use dietary therapy to relieve the cough, for example, you can cook garlic and rock sugar water, take 30 grams of garlic and 10 grams of rock sugar, add two large bowls of water, put them in a pot and boil for about 10-20 minutes, boil a small bowl of water left in the two large bowls, drink it while it is hot, it is more effective in treating cough. This is because garlic and rock sugar have the effect of moistening the lungs and relieving cough. However, if the cough is more serious, medication should be used to treat it. If the effect is not good, blood tests are needed. If elevated white blood cells and elevated neutrophils occur in blood tests, it means that the cough is caused by bacterial infection and needs to be treated with oral antibiotics, usually amoxicillin can be taken orally if there is no allergy to penicillin. If you do not see any results after taking the medication, you need to go to the hospital immediately.