Having contractions in the 6th month of pregnancy is abnormal and is a sign of preterm miscarriage, which needs to be treated with medication to preserve the pregnancy. You can take oral salbutamol 2mg every 6-8 hours, but you need to pay attention to the patient’s heart rate, if there is a rapid heart rate, panic, etc., you need to stop the drug. Magnesium sulfate can be administered intravenously, but not more than 30 grams per day. It is necessary to monitor the concentration of magnesium ions, as well as to observe whether the patient has knee reflex, breathing and urine output. If breathing is less than 16 breaths/min, urine output is less than 17 ml/h and knee reflex disappears, the drug needs to be stopped immediately and antagonized with calcium gluconate. Ritodrine can also be administered intravenously, but this should be done under cardiac monitoring, with attention to monitoring the patient’s heart rate and blood pressure. If the heart rate is greater than 120 beats/min, the drip rate should be slowed down, and if it is greater than 140 beats/min, the drug needs to be stopped immediately.