The use of drugs during pregnancy is directly related to the physical and mental health of the next generation. The physiological and pharmacological peculiarities of pregnant women, as well as the sensitivity of the fetus to drugs throughout pregnancy, have made the safety of medication during pregnancy a focus of attention. Pregnancy is a special stage, in the use of drugs for pregnant women should be considered from the mother and baby, weighing the pros and cons, to prevent improper use of drugs, to ensure the safety of mothers and babies. First, in the last century, the drug abuse of pregnancy (hexestrol, thalidomide) With the continuous improvement of medical and social conditions, perinatal drug use has become a growing concern. In the past, the use of drugs during pregnancy mainly considered the treatment of maternal diseases, but less consideration of the effects of drugs on the fetus and baby. in the early 1960s, the shocking global “reaction stop incident” led to thousands of fetuses with short limb deformities, which aroused a high degree of vigilance on the role of teratogenicity of drugs and a high degree of attention to the use of drugs in the perinatal period. 1. Hexoestrol and Vaginal Cancer in Teenage Girls Hexoestrol is a kind of drug widely used in the treatment of preterm miscarriage. 1966-1969, doctors of Boston Women’s Hospital in the U.S.A. found that 8 teenage girls suffered from vaginal cancer in a relatively short period of time, which is much more than the incidence of the disease in the teenage girls in the natural situation. After intensive epidemiologic investigation, it was demonstrated that the occurrence of these cases was causally related to the use of caprylyl estradiol by the mothers of the patients during pregnancy, the relative risk being greater than 132 times. Other hospitals have also reported one after another, until 1972, all over the world received a total of 91 cases of vaginal cancer patients aged 8-25 years old report, of which 49 patients’ mothers had taken hexenoestrol during pregnancy. 2, thalidomide and seal limb deformity Thalidomide (reaction stop) was first marketed in West Germany in 1956. Because it can be used for the treatment of pregnancy reaction, rapidly popular in Europe, Asia, Australia, North America (excluding the United States), Latin America, 17 countries. 1961 October, three German doctors in the West German gynecologists conference reported some seal limb deformities in children, attracted the attention of everyone. Later reports from other places followed, with many newborn infants having particularly short upper and lower limbs, or even no arms and legs, with hands and feet directly attached to the body. After a long epidemiological investigation, it was proved that this ‘seal limb deformity’ was related to the use of thalidomide by the mothers of the patients during pregnancy. The investigation found that the drug caused more than 10,000 deformities in several countries, with 6,000 to 8,000 cases in West Germany alone. The United States, Switzerland and the then East Germany were basically not affected by this incident due to the strict control on the approval of imported drugs. Second, the impact of pregnancy drug safety factors Pregnancy is a special period, the mother and the fetus is the same environment of the two closely linked independent individuals, the mother’s physiological response and sensitivity to drugs compared to the usual there are great differences, the fetus mainly rely on the placenta to obtain the necessary nutrients and excretion of metabolites, medication during pregnancy, due to the fetus of the mother’s dependence on the relationship, it is bound to bring about the growth and development of the fetus. The use of drugs during pregnancy will inevitably affect the growth and development of the fetus due to its dependence on the mother. 1, the pharmacokinetic characteristics of pregnant women: during pregnancy, gastric acid secretion is reduced, gastric emptying time is prolonged, intestinal peristalsis is weakened and slowed down, the peak absorption of orally administered drugs is often low, and pregnant women with early pregnancy reactions have worse oral effects; during pregnancy, the blood volume expands markedly, and the plasma flow increases by 35%, the blood is diluted, and the blood concentration of the drug decreases; during pregnancy, the renal blood flow increases, and the glomerular filtration rate increases by about 50%, and the renal efflux process may be accelerated, which will lead to a decrease in blood concentration, and a decrease in the concentration of the drug. This may lead to a decrease in blood concentration, and the half-life of the drug may be shortened, so the dosage and dosing interval during pregnancy are larger and shorter than those during non-pregnancy; plasma albumin decreases during pregnancy, the protein binding rate of the drug decreases, and the increase of the free drug in the blood may lead to an increase in the volume of distribution of the drug, and the burden on the liver is increased during pregnancy, and the hepatic removal of the drug is slowed down, and the decrease of renal blood flow in the supine position in the late stages of pregnancy may slow down the renal discharge of the drug, especially in those with hypertension, the renal function is affected by the increase of renal blood pressure. In the supine position in late pregnancy, renal blood flow is reduced, which can delay renal excretion of drugs, especially in those with hypertension, renal function is affected and drug excretion is slowed down. These characteristics may lead to drug accumulation in the body. 2, fetal pharmacokinetic characteristics: most of the drugs can enter the fetal body through the placenta, lipid solubility, dissociation degree is low, low protein binding rate of the drug is more likely to be transferred into the fetal body through the placenta, the drug can also be phagocytosed through the fetus amniotic fluid from the gastrointestinal absorption of small amounts. Drugs are mainly distributed in fetal liver, brain, heart and other organs, due to the imperfect development of fetal liver, drug metabolism enzyme deficiency, the detoxification ability of drugs is low, the glomerular filtration rate of the fetus is low, the excretion of drugs and degradation products is delayed. On the one hand, the transfer of drugs through the placenta to the fetus and its metabolites through the fetus to the mother and then metabolized, the latter process is often much slower compared to the speed, so the drug is easy to accumulate in the body of the fetus. On the other hand, the characteristics of fetal blood circulation cause uneven distribution of drugs, that is, drugs are easy to accumulate in organs with more blood, such as the liver, while in organs with less blood, such as lung infections, it is difficult to reach the local role, and the distribution of the imbalance is easy to lead to drug poisoning. 3. Fetal development: Within 2 weeks after fertilization, after the egg is laid, drugs have an “all” or “none” effect on the embryo. “All”: Harmful drugs destroy all or part of the embryonic cells, resulting in the early death of the embryo, leading to miscarriage. “No”: Harmful drugs do not damage the embryo or only damage a small number of cells, the cells at this stage have potential multidirectionality in function, which can compensate and repair the damaged cells, and the embryo can still continue to develop without any abnormality; 3-8 weeks after fertilization, the 15th-25th days, the central nervous system is in the stage of differentiation and development; 20th-30th days, the bones and muscles of the head and spine are in the stage of skeleton and muscle development and limb buds are in the stage of emergence; 20th-24th days, the embryo is in the stage of embryo development; 20th-24th days, the embryo is in the stage of embryo development. 20-24 days, is the embryonic organ differentiation and development stage, the cells begin to directional development, it is difficult to repair the damaged cells through differentiation compensation, when subjected to harmful drugs, it can produce morphological abnormalities and the formation of malformations, for the sensitive period of the drug, especially within 8 weeks of the high differentiation period, but also a highly sensitive period of the drug, the greatest risk of teratogenicity; 9 weeks to the full-term is the growth of the fetus, organ development, functional perfection stage From 9 weeks to full term is the stage of fetal growth, organ development and functional perfection, only the nervous system, reproductive system and teeth are still continuing to differentiate, especially the nervous system differentiation, development and growth is the highest peak in late pregnancy and neonatal period, when subjected to harmful drugs, due to the poor function of hepatic enzyme binding and high blood-brain permeability, resulting in fetal functional developmental delay (IUGR), low birth weight, functional behavioral abnormality, and an increase in preterm labor rate. There are almost no drugs that are absolutely safe in pregnancy, for this reason, unnecessary drugs should be avoided as much as possible. 4, pregnancy staging (safe period, high sensitivity, medium sensitivity, low sensitivity) Generally speaking, the time of taking the drug occurs within 3 weeks of pregnancy (3 weeks of menopause), known as the safe period. As the number of blastocyst cells is small at this time, once affected by harmful substances, the cell damage is difficult to repair and will inevitably cause spontaneous abortion. There is no need to worry about giving birth to a deformed child if you take the medicine at this time. If there is no sign of miscarriage, it generally means that the drug has not affected the embryo and the pregnancy can continue. The third to eighth week of pregnancy is called the high-sensitivity period. At this time, the embryo is most sensitive to the effects of drugs, teratogenic drugs can produce teratogenic effects, but does not necessarily cause spontaneous abortion. At this time should be based on the size of the drug side effects and related symptoms to judge, if there is vaginal bleeding related to this, should not blindly preservation of pregnancy, should be considered to interrupt the pregnancy. The period from 8 weeks to 4-5 months of pregnancy is called the middle sensitive period, which is the period of further development and maturation of fetal organs, and it is more sensitive to the toxic side effects of drugs, but most of them do not cause spontaneous abortion, and the degree of teratogenicity is unpredictable. Whether to terminate the pregnancy at this time should be based on the size of the toxic side effects of the drug and other factors should be considered in a comprehensive manner, weighing the pros and cons before making a decision. Continuing pregnancy should be in the middle and late pregnancy for amniotic fluid, ultrasound and other examinations, if found fetal abnormalities should be induced; if chromosomal abnormalities or inborn metabolic anomalies, depending on the severity of the disease and the prognosis, or terminate the pregnancy as soon as possible, or to be intrauterine treatment. Above 5 months of pregnancy is called hypoallergenic period. At this time, the fetal organs have basically developed, the sensitivity of the drug is low, the use of drugs does not often appear obvious deformities, but there can be varying degrees of developmental abnormalities or limited damage, such as sleeper caused by fetal growth retardation, phenobarbital caused brain damage, streptomycin, quinidine caused by deafness and so on. At this time, the drug must be very careful. Third, pregnancy drug risk level During pregnancy, the fetus is connected to the mother through the placenta. The mother delivers the nutrients contained in the blood to the fetus through the placenta for its growth and development. The fetus passes metabolites through the placenta to the mother, who eliminates them on her behalf. When a pregnant woman takes a drug, the drug enters the bloodstream and passes through the placenta to the fetus. Therefore, it may cause adverse effects on the growth and development of the fetus. In 1979, the U.S. Food and Drug Administration (FDA) for the possible effects of drugs on the fetus, drugs are divided into five categories, this classification is now widely accepted and used around the world: 1, the concept of classification of drug risk level Class A: controlled studies have not been found in the gestation period of the human fetus will have a risk, this type of drug may have little effect on the fetus. Class B:Animal studies have not found a risk to the animal fetus, but there are no control groups in human studies; or adverse effects have been shown in animal reproduction studies, but no adverse effects have been demonstrated in well-controlled human studies. Category C:Adverse effects on the fetus have been shown in animal studies, but there are no controlled studies in humans; or there is no information on human and animal studies. Use this class only if the potential benefit to the fetus outweighs the potential risk. Class D:There is firm evidence of risks to the human fetus, but these risks are acceptable for the benefit of the pregnant woman, e.g., in life-threatening situations, or in severe conditions where only safe medications are ineffective. RATING X: The drug has been shown to cause fetal anomalies in animal or human studies, or to pose a risk to the fetus based on human experience, or both, and the potential risks clearly outweigh the therapeutic benefits. This class of drugs is contraindicated in pregnant women or women who may already be pregnant. 2. The safety of drugs commonly used in clinical practice is summarized as follows: Class A: Fetal safety. There are very few drugs in this class. Vitamins belong to this class, such as vitamin B and vitamin C in appropriate doses. However, vitamin A in the normal range of the amount of vitamin A is a class A drug, while large doses of vitamin A, daily dose of 20,000 IU, can be teratogenic, and become a class X drug. Class B:Relatively safe. There are not many drugs in this class, and some of the commonly used antibiotics belong to this class, such as all penicillins and the vast majority of cephalosporins are class B drugs. Lincomycin, clindamycin, erythromycin, and furotoxin are also class B drugs. Although metronidazole can be teratogenic to rodents in animal experiments, in humans, a large amount of clinical data accumulated over a long period of time confirms that early pregnancy application, and did not increase the rate of fetal teratogenicity, so the FDA placed it in Class B. The anti-tuberculosis drug ethambutol is a Class B drug. The antipyretic and analgesic drugs indomethacin (anti-inflammatory pain), diclofenac, ibuprofen are class B drugs. It should be noted that taking indomethacin after 32 weeks of pregnancy may cause fetal arterial stenosis or atresia, resulting in fetal death, so indomethacin should not be taken after 32 weeks. The cardiovascular system drugs digitalis, digoxin and cediran are class B drugs. Prednisolone, an adrenocorticotropic hormone, is also a Class B drug. Class C:Use with caution on balance. There are more drugs in this class, which are either not introduced for a long enough period of time or less frequently used in pregnant women, mainly because there is no report on whether early pregnancy application will cause damage to the embryo and fetus, so it is difficult to have a more definite conclusion. The use of caution, try to use alternative drugs, if necessary, after weighing the pros and cons, to the patient or family members to explain the reasons for the choice of the drug. Most antiviral drugs belong to category C, such as acyclovir and zidovudine for AIDS. Some antiepileptic drugs and tranquilizers such as ethosuximide, barbiturates, pentobarbital, etc. Among autonomic nervous system drugs, cholinergics and anticholinergics belong to category C. Some of the adrenergic drugs belong to category C, such as epinephrine, ephedrine, and dopamine. Among antihypertensive drugs, methyldopa, prazosin and all commonly used vasodilators belong to class C. Among diuretics, furosemide (tachycardia) and mannitol are class C drugs. Among the adrenocorticotropic hormones, betamethasone and dexamethasone are class C drugs. Class D:Use as a last resort. Because of the experimental and clinical evidence available, drugs classified as class D should not be used in pregnancy, especially in the early stages of pregnancy. Typical examples are the tetracyclines, which, when used during pregnancy, destroy the enamel of the fetus and cause yellowing of the teeth in adulthood. Aminoglycosides, such as streptomycin, are not used in pregnancy and may damage the VIII brain nerve and cause hearing loss. Antineoplastics are almost always class D drugs. Analgesics are class B drugs when used in small doses, and class D drugs when used in large doses, especially when applied for a long period of time, which mainly manifests itself in poor fetal growth and development as well as addiction to the drug after delivery. Among antipyretic and analgesic drugs, aspirin, divalproex, and salicylic acid are class C drugs when used in small doses, but become class D drugs when taken in large doses for long periods of time. Antiepileptic drugs are almost always class D. Their use is directly associated with adverse fetal outcomes and the risk increases with the number of drugs used; the most commonly reported malformations are orofacial clefts, cardiac malformations, neural tube defects, and developmental delays. It is important to note that pregnancy in patients with epilepsy is associated with a higher rate of fetal malformations than in the general population, and the use of antiepileptic drugs increases the rate of malformations even more, especially when several antiepileptic drugs are used concomitantly for difficult-to-control seizures, which is something that must be made clear to the patient and the family when diagnosing and treating epilepsy in combination with pregnancy. Sedative and hypnotic drugs such as diazepam, chlordiazepoxide and desoxazepam are class D drugs. Hydrochlorothiazide and benserazide among diuretics are class D drugs. Coumarin derivatives (bicoumarin, bicoumarin ethyl ester, warfarin) are class D drugs with low molecular weights that can readily pass through the placenta and cause significant malformations and fetal defects. Miscarriage, intrauterine fetal death, and neonatal anomalies occur in approximately 1/6 of warfarin-exposed pregnancies. Fetuses are at risk of developing warfarin syndrome (FWS) when exposed to warfarin in early pregnancy, and the most dangerous period of exposure to such drugs is 6-9 weeks of gestation, when the incidence of FWS can be as high as 25%. Fetal exposure to warfarin during the middle and late trimesters can cause fetal central nervous system defects, generally due to early fetal hemorrhage and secondary scarring, followed by deformities causing abnormal growth and development of brain tissue, and for infants central nervous system defects, although rare, are more clinically significant than FWS. If the mother requires anticoagulation, the use of heparin from the end of the 6th to the end of the 12th week of gestation, followed by a switch to warfarin, and then again to heparin after full term, reduces adverse fetal outcomes. In fact, there are thousands of drugs available for people to use, and there are class B, C, and D drugs in each category; class B or C drugs should be chosen over class D drugs whenever possible. Class X: absolutely prohibited. There are not many of these drugs in common use, but they are prohibited during pregnancy due to high teratogenicity rate or great harm to the fetus. Known teratogenic drugs are: angiotensin-converting enzyme inhibitors (ACEI), alcohol, androgens, marilan (leucovorin), carbamazepine, chlorobiphenyl, cyclophosphamide, danazol, ethinyl estradiol, retinol, isotretinoin, lithium, methimazole, methotrexate, penicillin, sodium phenytoin, radioactive iodine, tetracycline, valproate, trimethoprim and so on. Herbal and botanical medicines:It is difficult to estimate the risk or safety of these medicines; often, the composition and dosage of the medicines are unknown, and there are no reports of human or animal studies on their teratogenic potential, and knowledge of their complications is limited to acute toxic reactions. Since the safety of such drugs for the developing fetus cannot be assessed, pregnant women should be advised to avoid their use as much as possible. Fourth, common complications of pregnancy drug treatment and commonly used drugs (hypertension, diabetes, colds, vitamins) 1, hypertension Hypertensive disorders in pregnancy is a group of hypertensive disorders seen in pregnancy, including: (1) gestational hypertension: blood pressure ≥ 140/90 mmHg, first found during pregnancy, and blood pressure returns to normal within 12 weeks after delivery, no urinary protein, the patient may be accompanied by epigastric discomfort or thrombocytopenia, and the diagnosis can only be confirmed after delivery. (2) Pre-eclampsia: It is divided into mild and severe pre-eclampsia. Mild: blood pressure ≥140/90mmHg, urine protein ≥0.3g/24h or urine protein (+) for the first time after 20 weeks of pregnancy; Severe: any one or more of the following: blood pressure ≥160/110mmHg, urine protein (++), proteinuria ≥5.0g/24h, creatinine >106μmol/L, platelets <100×109/L, lactate dehydrogenase rise, liver enzymes rise. dehydrogenase rise, liver enzymes rise, persistent headache or other cerebral neurologic or visual disturbances. Patients with gestational hypertension are categorized as preeclampsia once proteinuria occurs. (3) Eclampsia: Convulsions or coma in pregnant women with preeclampsia that cannot be explained by other causes. (4) Chronic hypertension complicating preeclampsia: pregnant women with chronic hypertension have no urinary protein and develop urinary protein ≥300mg/24h after 20 weeks of pregnancy; proteinuria increases suddenly or blood pressure increases further after 20 weeks or platelets <100×109/L are present. (5) Chronic hypertension in combination with pregnancy: blood pressure ≥140/90mmHg, hypertension has been diagnosed prior to conception or before 20 weeks of pregnancy, and it persists after delivery. persists after 12 weeks. Hypertension in pregnancy is considered an important cause of maternal and in utero fetal death and neonatal death. The use of antihypertensive drugs during pregnancy should take into full consideration the effects of the drug on the mother and on the fetus through the placental blood. In addition, antihypertensive drugs can lead to a rapid decrease in the perfusion pressure of the organs, which can lead to low cardiac output of the mother as well as a decrease in blood flow through the uteroplacental placenta, which may induce fetal asphyxia, and therefore must be applied with care. The aim of the treatment is to enable the patient to avoid the emergency state of severe hypertension as well as chronic hypertension and to continue the pregnancy, thus requiring a gentle lowering of the blood pressure. Central antihypertensive drugs:The drug recommended by the British Hypertension Society (BHS) for the treatment of chronic hypertension in pregnancy is methyldopa, which is still the first-line drug for hypertension in pregnancy. Some antihypertensive drugs for hypertension in pregnancy, such as beta-blockers, peripheral vasodilators and calcium antagonists, are often used as a control. Calcium antagonists:Whether their use in early pregnancy (within the third month) increases the risk of fetal malformations is still controversial. However, when nifedipine is used in the treatment of hypertension in pregnancy, it has a mild antihypertensive effect, does not decrease cardiac output, and has the effect of inhibiting contractions. Some studies have shown that nifedipine does not affect labor or increase postpartum hemorrhage, and can be used as a first-line antihypertensive drug. There are reports suggesting that when administered sublingually or intravenously, a rapid and excessive drop in blood pressure has led to myocardial infarction or fetal distress. Therefore, controlled-release or extended-release dosage forms are mostly preferred for smooth BP lowering. The newer generation of drugs, such as irradipine, nimodipine, and nicardipine, are highly vasoselective and have a weak effect on uterine contractions during and after labor, and can be used with greater confidence in the treatment of hypertension in pregnancy. However, it is important to note that calcium antagonists should not be combined with magnesium sulfate, which is commonly used in the treatment of eclampsia, because the effect of magnesium sulfate can be enhanced by calcium antagonists, which may lead to sudden and severe hypotension. Beta-blockers:The effectiveness of beta-blockers in gestational hypertension has been demonstrated, and their short-term use in the second trimester is considered safe. However, they can cause intrauterine growth retardation, neonatal respiratory disturbances, and hypoglycemia due to their ability to cross the placenta and reduce blood supply to the uterus and placenta. Indolol and atenolol have these effects and should not be used in the early or mid-term. Vasodilator:Hydrazinobenzopyridazine is a direct vasodilator drug, with obvious dilatation effect on small arteries, obvious effect on lowering diastolic blood pressure, not affecting the uteroplacental circulation, and no adverse effect on the fetus. Intravenous medication in foreign countries as the first choice of drugs for severe hypertension in pregnancy. Diuretics:The antihypertensive effect is relatively weak, and the application of diuretics in the early stages of pregnancy, so that the maternal blood volume can not be expanded to the normal level of pregnancy, which may contribute to the occurrence of pre-eclampsia. Thiazide diuretics have been shown to cause fetal and neonatal jaundice, hypokalemia, thrombocytopenia, and other adverse effects, and excessive use should be avoided in principle. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor antagonists (ARBs):Used in mid- and late-term pregnancies, ACEIs can lead to fetal abnormalities such as oligohydramnios, pulmonary hypoplasia, fetal growth retardation, renal hypoplasia, neonatal anuria and neonatal death. ACEIs are contraindicated in mid and late pregnancy or are usually contraindicated in pregnancy because they can cause fetal renal insufficiency. ARBs should not be used in pregnancy because they can cause fetal malformations and stillbirths. 2, Diabetes Gestational diabetes mellitus (GDM) refers to varying degrees of abnormal glucose tolerance that occurs or is first detected during pregnancy. The effect of pregnancy on diabetes: pregnancy increases the demand for insulin in pregnant women. Pregnancy makes it more difficult to diagnose and treat diabetes mellitus: loss of appetite and violent vomiting in the early stage of pregnancy; increased physical exertion and decreased food intake during labor and delivery, resulting in a large amount of glycogen consumption; after delivery, insulin requirements plummet due to the delivery of the placenta; the renal excretion threshold is lowered, and urine glucose does not accurately reflect the condition; it is easy to cause ketoacidosis, hypoglycemia and other complications. Effects of diabetes on pregnant women: high incidence of hypertensive disorders during pregnancy; high incidence of infections, which can easily cause ketoacidosis; other obstetric complications: excessive amniotic fluid, amniotic membrane infections, premature rupture of membranes, preterm labor, etc.; high rate of postpartum hemorrhage. Effects of diabetes mellitus on fetus: high incidence of macrosomia; high incidence of malformed fetus; high incidence of fetal growth restriction, fetal distress, stillbirth. Effects of diabetes mellitus on neonates: high incidence of neonatal hypoglycemia; high incidence of neonatal respiratory distress syndrome. (1) Dietary and nutritional therapy is very important for GDM patients. Some GDM patients only need dietary and nutritional control to maintain their blood glucose in the normal range, therefore, all GDM mothers should receive nutritional counseling from dietitians as much as possible, and individualized nutritional treatment plans should be formulated. (2) Exercise therapy for GDM has received widespread attention and recognition. Women who maintain regular exercise before and during pregnancy can reduce the occurrence of GDM. Appropriate exercise can also reduce the chances of type 2 diabetes mellitus occurring after delivery in pregnant women with GDM. (3) Insulin is the main therapeutic drug for GDM patients who cannot be controlled by diet and nutritional therapy. (4) The treatment of GDM with oral hypoglycemic agents is still controversial. Oral hypoglycemic therapy has been listed as contraindicated in pregnancy due to the special characteristics of medication in pregnancy. Previous studies have concluded that oral hypoglycemic agents should be contraindicated in pregnancy because of the increased risk of fetal malformations. However, a growing number of new findings suggest that some oral hypoglycemic agents are safe and effective for pregnant women with diabetes. In 2009, the American College of Obstetricians and Gynecologists (ACOG) reported that 13% of obstetricians and gynecologists in the U.S. currently use glibenclamide as a first-line drug for GDM. 3, cold and flu General cold and flu, the symptoms are mild, such as runny nose, sneezing, the impact on the fetus is not great, and do not have to take medication, rest for a few days will be good. However, in early pregnancy (5-14 weeks), mainly fetal embryonic development of organ formation time, if suffering from influenza, and the symptoms are more serious, the impact on the fetus is greater, this period of time to take medication for the fetus also has a greater risk. For mild colds, pure proprietary Chinese medicines such as Banlangen Punch can be used. Drink plenty of water and take rest, and the cold will be cured soon. If you have a high fever and cough, you can use Chai Hu injection to reduce fever and pure Chinese medicine cough syrup to stop coughing. At the same time, you can also use a wet towel cold compress, with about 30% alcohol (or white wine to dilute double) bath, physical antipyretic effect. Antiviral drugs have adverse effects on the fetus, pregnant women should not be used, if you must use, should be guided by a doctor. Anti-inflammatory pain is contraindicated in pregnant women antipyretic, aspirin should not be used after 32 weeks of pregnancy. Expectorant, cough medicine is generally safer, but iodine-containing cough medicine, pregnant women should not use. 4, vitamins In accordance with the FDA grading standards, for pregnant women, the same drug (refers to certain drugs) can have two different levels of harm, the harm is due to the different doses of medication, one is the level of the common dose, the other is the level of the abnormal dose. For example, vitamin A, the normal dosage is a class A drug, is safe for pregnant women, pregnant women vitamin A daily dosage of no more than 5000 U, and large doses of vitamin A, daily dose of more than 15,000 U, can cause teratogenicity, and become a class X drug, class X drugs are prohibited for women who are pregnant or will be pregnant. Large doses of vitamin D can cause fetal hypercalcemia and retarded intellectual development. Large amounts of vitamin K can cause fetal hyperbilirubinemia and kernel jaundice. Large amounts of vitamin B6 can cause vitamin B6 dependence and convulsions in newborns. Fifth, the principle of safe use of drugs during pregnancy 1, pre-pregnancy physical examination, and strive for pregnancy in a healthy state. 2, the application of any drug must be taken under the guidance of doctors and pharmacists. 3, if a chronic disease is found before pregnancy, the use of medication should take into account the continuity and safety of medication during pregnancy, to avoid the use of drugs that may endanger the fetus. 4, early pregnancy (within 12 weeks) try not to use drugs. 5, try to avoid the combination of drugs. 6, with the conclusion of the more certain drugs, avoid using new drugs. 7, do not use their own random medicine or listen to biased prescriptions, secret prescriptions to prevent accidents. 8, the use of drugs, pay attention to the bags of pregnant women with caution, contraindicated, prohibited words. 9, must be used when the drug, try to choose to the fetus without damage or small impact of the drug. 10, pregnant women who accidentally take teratogenic or potentially teratogenic drugs, should be under the guidance of a doctor, according to the time of pregnancy, the amount of medication, medication time and other comprehensive consideration of whether to terminate the pregnancy. 11, most of the instructions of proprietary Chinese medicines are relatively simple, many instructions are not set up in the pregnant woman medication precautions, because it is difficult to weigh the advantages and disadvantages of pregnant women, should be careful with the medication, to ensure the safety of medication. Sixth, the correct treatment Do not talk about drugs, in fact, the probability of drug teratogenicity is very small, obstetricians need to pay attention to the impact of the disease itself on the fetus and the impact of drugs on the fetus. Sometimes the disease itself on the fetus is more serious, the doctor's use of drugs is a process of weighing the pros and cons, the doctor and the patient should consider the risk of treatment of the disease and the risk of not treating the lesser of the two, to increase the adherence to the treatment of the disease during pregnancy, to maintain a happy psychological state during pregnancy is very important for themselves and the fetus. In conclusion, medication in pregnancy, absolute safety of therapeutic drugs is almost none, so to avoid unnecessary use of drugs, especially in early pregnancy should be avoided as much as possible. For the possible adverse effects of medication, preventive measures should be taken as far as possible to minimize the degree of harm of medication to the fetus and the pregnant woman.