this time, the most suitable age for giving birth to children is 26 ~ 35 years old, and the death rate for men is the lowest. With the age of women's pregnancy is too old, the chance of congenital malformations and congenital stupid infants increases.

In addition, from Darwin's personal experience, we must avoid close relative marriage.

Professor Xin Hong from the second hospital of Hebei Medical University talked about the problems of birth defects and nutrition during pregnancy. First, she said that the imbalance of nutrition during pregnancy will not only lead to maternal abortion and premature birth; Anemia, hypoproteinemia and calcium deficiency; Pre eclampsia, obesity, metabolic disorder, pregnancy complications, increased cesarean section, dystocia, soft tissue injury, postpartum learning and affecting postpartum body recovery; Moreover, it will lead to birth defects, affect the development of various organ systems (brain and bone), neonatal birth weight and mortality, slow development, low birth weight infants, weak resistance, risk of macrosomia, birth injury, neonatal asphyxia, childhood anemia, childhood obesity and other problems.

The lack of multiple nutrients in pregnant women in China is very common, which is reflected in that the demand for nutrients during pregnancy is much higher than that before pregnancy and that the intake of multiple nutrients in pregnant women in the middle and third trimester of pregnancy is far lower than the recommended value. Here, she specially reminds the majority of women of childbearing age to pay attention to the timely and appropriate supplement of folic acid. For example, the supplement of folic acid during pregnancy can prevent birth defects, the supplement of vitamin D can reduce the risk of preeclampsia, and the supplement of iron can reduce the risk of neonatal asphyxia. Therefore, balanced nutrition can prevent birth defects and reasonable diet can reduce pregnancy diseases, adult diseases, fetal origin and healthy life from conception.

Professor Cao Qinying from Shijiazhuang maternity hospital in Hebei Province is an experienced expert in maternal and infant health prevention. Her Shijiazhuang prenatal diagnosis center is the only prenatal diagnosis center in Hebei Province. In this seminar, she mainly talked about the three-level prevention of birth defects.

Birth defects, also known as congenital abnormalities, refer to structural and functional abnormalities in the embryo or fetus. Birth defects are the leading cause of death within one year of birth. Birth defects are the leading cause of death within one year of birth.

Birth defects are a heavy burden on society and families. Common birth defects include morphological abnormalities (deformation defects, cleavage defects, dysplasia, malformation defects), dysfunction (metabolic diseases) and chromosomal diseases (polygenic diseases such as congenital heart disease, dominant or recessive monogenic diseases).

The three-level prevention of congenital defects mainly includes the first level prevention based on etiology; Prenatal diagnosis and the secondary prevention of termination of pregnancy in perinatal department; The third level prevention of congenital defect correction. The effect of primary prevention is the best, just as our current medical advocacy of "scientific treatment of diseases".

She also said that although the marriage law revised the past compulsory premarital examination to "voluntary premarital examination" in 2003, it still advocates 18 premarital examinations for couples who are ready to enter the palace of marriage to promote family planning. In fact, Premarital Check-up is free. However, the coverage rate in urban areas is only 60% and that in rural areas is 10%. In addition, he also recommended pre pregnancy health care, health education and counseling, and health status assessment.

Professor Lu Guangxiu from CITIC Xiangya reproductive and genetic hospital and the National Engineering Research Center of human stem cells believes that andrology is men's science. It studies men's health, especially problems related to men's reproductive system and urinary system. Internationally, andrology, as a unique specialty, originated in the 1960s. Its fields involve reproductive anatomy, physiology, biochemistry, embryo, genetics, microorganism, immunity, pathology, cell biology, molecular biology, etc. of basic medicine. The progress of genomics technology has promoted human understanding of Andrology diseases, increased expectations for the accelerated development of andrology, and provided new hope for the prevention and treatment of refractory andrology diseases, such as sperm function analysis and evaluation of start candidate genes, genetic evaluation of male reproductive endocrinology, etc. At the same time, with the continuous development of stem cell technology, human beings are expected to eradicate the problem of male infertility.

In the past, China has always advocated "late marriage and late childbirth", but now most young people are in the age of late marriage and late childbirth, and will be 3 to 5 years late. In this case, the profession calls on couples to receive prenatal diagnosis before they are ready to conceive, so as to prevent the inheritance of genetic diseases.

Professor Huang Shangzhi from the basic college of Peking Union Medical College, the Department of medical genetics of the Institute of basic medicine of the Chinese Academy of Medical Sciences and the WHO Cooperative Center for community control of genetic diseases mentioned that prenatal diagnosis is a high-risk thing for medical institutions. Therefore, at present, the fees for various prenatal diagnosis are relatively high. If prenatal diagnosis can be carried out nationwide, the price of prenatal diagnosis will be reduced. Who is more important in "prenatal diagnosis vs postpartum diagnosis?" In the discussion of this issue, participants agreed that prenatal diagnosis is more important than postpartum diagnosis.

Chen yingyao made the "economic evaluation of prenatal screening (diagnosis) strategy for the prevention of Down syndrome". He believes that the economic benefits brought by prenatal diagnosis are not great, but because it is related to the happiness of millions of families, this work is still very valuable and cannot be viewed from the perspective of pure commercial value. There is no 100% accurate prenatal diagnosis method, but prenatal genetic diagnosis is the future trend, which is the least harmful to pregnant women.

B-ultrasound is a common method to check fetal malformations, but it should be noted that not all abnormal fetuses can be measured by B-ultrasound. For congenital stupid or small abnormal children caused by chromosome abnormalities, B-ultrasound cannot be measured.

Some elderly pregnant women (aged > 35), those who have given birth to congenital stupid children, those who have abnormal chromosome balance on one side of the couple, those who have a history of sex linked diseases in the family (such as hemophilia, pseudohypertrophic muscular dystrophy, red-green blindness, etc.), those who have given birth to children with intellectual impairment of unknown cause, congenital malformations, multiple spontaneous abortions, and those who have a history of special drugs or contact in the early pregnancy need prenatal diagnosis.

In the past, due to the influence of growth background, education level and environment, couples did not know enough about some common knowledge of pregnancy preparation. Experts at the conference have called for "genetic counseling" to be included in the important link of prenatal diagnosis.

In addition, there are many new technologies that can be used for prenatal diagnosis. For example, Professor Yin Aihua from the medical genetics center of Guangdong maternal and child health hospital introduced the application of array CGH technology in prenatal diagnosis, which can be suitable for those who want to carry out high-resolution chromosome examination to reduce the risk of pregnancy. The traditional chromosome has found abnormalities, but it is impossible to determine the location of abnormal structures or whether there is gene dose Fetal ultrasound examination has structural abnormalities, family history of congenital abnormalities or babies with congenital abnormalities, but the cause cannot be found by traditional chromosome examination.

科普：几种常见的遗传病

Diabetes: diabetes is an endocrine metabolic disease with a family genetic tendency. The genetic tendency of type ⅱ is more significant than that of type ⅰ diabetes.

Heart disease: if parents suffer from heart disease, their children are 5-7 times more likely to have heart disease than their parents' children without heart disease.

Hypertension and hyperlipidemia: if one of the parents suffers from hypertension or hyperlipidemia, the child's risk of disease is 50%; If both parents have high blood pressure or hyperlipidemia, the probability will increase to 75%.

Obesity: if one of the parents is obese, the possibility of the child being overweight is 40%; If both parents are obese, the probability increases to 70%. Even so, as long as the child always adheres to a healthy diet and exercise, he can grow into a normal weight child.

High myopia: there is a certain relationship between myopia and heredity. Especially when both parents are high myopia, the probability of myopia in children will be greater. Even if they are not myopia at birth, they may develop myopia once affected by the environment. The number of people who become myopia due to genetic factors accounts for only 5% of the total number of myopia. The influence of acquired environment and habits can not be ignored.

Skin cancer: melanoma is an uncommon but very deadly skin cancer. If one of the parents has melanoma, the child's chance of getting sick is 2% to 3%; If both parents have melanoma, the probability will increase to 5% to 8%; If parents are diagnosed with melanoma before the age of 50, their children will be more likely to get sick.

Rhinitis: many nasal diseases are inherited. For example, the most common allergic rhinitis, chronic rhinitis and chronic sinusitis, all of which have a family genetic tendency.

Mental illness: if one parent is schizophrenic, the incidence rate of their children is about 15%. If both parents are schizophrenic, the incidence rate of their children is about 40%.

Baldness: only to men. For example, if the father is bald, the probability of passing it on to his son is 50%. Even the mother's father will leave the 25% probability of his bald head to his grandchildren. This gender genetic tendency of transmitting men to women leaves men helpless.

Hemophilia: a typical sex related genetic disease. Only boys will get sick. Female gene carriers will pass the pathogenic gene to their offspring, and half of their male offspring may get sick. Diseased men usually die before adulthood without passing on the gene.

Breast cancer: the familial genetic prevalence rate is 7-8 times higher than that of ordinary people. Breast cancer is a disease with obvious genetic characteristics. If more than one person in a family has breast cancer, it should be suspected whether it is hereditary breast cancer.

Depression: a woman has a 10% chance of inheriting emotional instability from her mother.

Overweight: Women's weight is more closely related to their mother's weight and body shape than their father. The weight genetic factors of obese people account for 25% - 40%.

Osteoporosis: the mother suffers from osteoporosis, and the daughter has a high incidence rate of brittle bones, so they are also more likely to fracture, hunchback, stoop, hip fracture, etc.

Thalassemia: thalassemia is a genetic disease, which is common in Guangdong and Guangxi provinces, Hunan, Hubei, Anhui and Fujian provinces in China. You should go to the Hematology Department of the hospital for detailed examination and diagnosis.