Changes in respiratory function occur early in pregnancy, and at 18 weeks, the pregnant woman’s oxygen consumption increases by 10-20% (50% of which is consumed by the fetus). While the ventilation of the lungs increases by up to 40%, pregnant women tend to hyperventilate in order to meet the oxygen demand of the pregnant woman herself and the fetus. The fetus has no respiratory function in the mother’s body and is completely dependent on the mother to inhale oxygen and expel carbon dioxide, so pregnant women often feel short of breath and have difficulty breathing. Due to hyperventilation, more dust is inhaled, plus the mucous membrane of the respiratory tract such as the nose, pharynx and trachea of pregnant women is congested and edematous is easy to have upper respiratory tract infection. Due to the increased demand for oxygen in pregnant women, the condition is more likely to worsen when the pregnancy is combined with off respiratory diseases. What kind of cold has an effect on the fetus? A common cold with mild symptoms, such as runny nose and sneezing, has little effect on the fetus, and there is no need to take medication, and the fetus will recover after a few days of rest. However, in the early stage of pregnancy (5~14 weeks), which is mainly the time when the fetal embryonic development organs are formed, if you have influenza with severe symptoms, it will have a greater impact on the fetus, and taking medication during this period will also have a greater risk to the fetus. There are more than 300 types of influenza viruses known to be associated with humans, and 13 of them are known to affect the growth and development of the fetus after infection of the mother, with imbecility, mental retardation, various malformations, premature birth, miscarriage, and even stillbirth. The first 3 months of pregnancy: During these 3 months, pregnant women should be prohibited from taking all drugs, and if they have a cold, they should be treated separately according to the following two situations. Situation 1: The cold is not feverish, or the temperature does not exceed 38 degrees when fever is present. In this case, pregnant women usually have mild cold symptoms such as runny nose and sneezing, which can be left untreated and will have no effect on the fetus. If a pregnant woman has cough and other symptoms, she can take medicines that are safe and have no effect on the fetus under the guidance of a doctor. Situation 2: If a pregnant woman has a fever of 39 degrees or more and it lasts for more than 3 days. If a pregnant woman has a cold within 2 weeks after ovulation, she can take medicine without affecting the fetus. If the flu occurs after 2 weeks of ovulation, the medication may affect the fetus because the central nervous system of the fetus has already started to develop. In this case, the doctor may advise the pregnant woman to terminate the pregnancy. Mid-pregnancy: At this time, medication should be used carefully. Drugs like gentamicin, streptomycin and kanamycin that are damaging to the auditory nerve should be used with caution, and it is best to try not to use them. In case of fever, ask your doctor to choose some herbal medicines with less toxic side effects. The herbal medicines such as Banlangen, Da Qing Ye, Lian Qiao, Qiang Wu and Jinyin Hua, which have the effect of clearing heat and detoxifying and anti-viral, have better efficacy. Chinese herbal medicines such as Yin Qiao Detoxification Pill, Compound Da Qing Ye Injection, Yin Huang Oral Liquid can be taken. For the common anti-cold medicine such as quick-acting cold capsule, cold pass, Contec, Baijiahei, Kangbid, Ksenkang, Quick, etc., most of these drugs contain histamines, should not be taken. If the cold is accompanied by a high fever, more signs of a serious condition should see a doctor in a timely manner, do not take anti-inflammatory pain, which is a contraindicated anti-fever medicine for pregnant women. Late Pregnancy: At this time, taking cold medicine generally does not have much effect on pregnant women and fetuses. You can choose the appropriate medication under the advice of your doctor. No medication is not advisable. After pregnancy, pregnant women’s body enzymes have certain changes, which have certain effects on the metabolic process of certain drugs. Drugs are not easily detoxified and excreted, there can be accumulative poisoning, in early pregnancy when the fetal organs are formed, drugs have a certain impact on the fetus, so it is best not to take drugs for colds. But everything is divided into two, pregnant women use drugs have certain risks, but not completely unhelpful. The impact of some diseases themselves on the fetus and mother far exceeds the impact of drugs, so it is important to weigh the pros and cons and use the drugs reasonably under the guidance of a doctor. The main drug pros and cons Anti-cold drugs are mostly compound preparations, containing a variety of ingredients, common quick-acting cold capsules, cold pass, Contec, white plus black, Compeed, Ksenko, fast and so on, most of these drugs contain histamines, should not be taken during pregnancy, especially before the fourth week of pregnancy, cold drugs are mainly symptomatic drugs, treating the symptoms but not the root cause, and not safe for pregnant women, so it is recommended that pregnant women are best not to use anti-cold drugs. 1, antiviral drugs: all have adverse effects on the fetus, pregnant women should not use, if you must use, it should be under the guidance of a doctor. 2, antipyretic drugs: cold with high fever, much sign of a serious condition should see a doctor in a timely manner. Anti-inflammatory pain is a contraindicated antipyretic drugs for pregnant women, aspirin should not be used after 32 weeks of pregnancy. 3, antibacterial agents: pregnant women with colds such as no clear evidence of bacterial infection, such as tonsillitis, high blood pressure, coughing yellow sputum, runny nose, etc., can be used without antibacterial agents. Because antimicrobial agents can act on the fetus through the placenta, there is a 20% to 40% possibility of posing a danger to the fetus, so choose safe antimicrobial agents under the guidance of a doctor. 4, expectorant, cough medicine: generally safe, but the cough medicine containing iodine preparation, pregnant women should not use. Prevention is most important. Women during pregnancy should pay attention to rest, strengthen exercise, maintain a strong body, pay attention to personal hygiene during the disease epidemic, do not go to densely populated places, do not contact patients with colds, ventilate the home room, keep the temperature and humidity appropriate, often fumigate the room with vinegar, maintain a good state of mind, enhance the resistance to disease. Once you have a cold, you should not panic or take drugs indiscriminately, and you should not ignore it, but go to the hospital for consultation.