I. Prenatal screening
1. How long is the most appropriate time to do fetal ultrasound?
The best time for the first fetal ultrasound is during the period from the 11th week to the 6th day of the 13th week of pregnancy. At present, scholars at home and abroad are very concerned about fetal ultrasound examination during this period, and the main purposes are as follows.
First, to assess the gestational age, determine the number of embryos, and evaluate the number of amniotic sacs and chorionic villous sacs in multiple pregnancies;
The second is to screen for Down’s syndrome: it is recommended that pregnant women have a fetal nuchal translucency (NT) test during this period to determine whether the fetus has Down’s syndrome.
Third, early diagnosis of certain serious fetal malformations, such as conjoined twins;
Fourth, evaluation of masses in the uterus or adnexa.
In addition, fetuses with severe structural malformations can also be diagnosed by ultrasonography during this period.
The best time for the second examination is from the 18th to the 26th week of pregnancy, mainly for structural malformations, when congenital heart disease, polycystic kidney and lethal dwarfism can be diagnosed by ultrasound.
The third examination is after the 30th week of pregnancy, which is a “fill-in” examination, some late-onset fetal malformations, such as hydrocephalus, digestive tract malformations, etc. can be diagnosed at this time.
2. Prenatal screening.
From 14 to 20 weeks of gestation, screening for neural tube defects and Down’s syndrome is carried out to identify possible high-risk groups for neural tube defects and Down’s syndrome among normal pregnant women, and then further prenatal diagnosis is done for these people, which can prevent 65-90% of the births of children with congenital dysfunction and neural tube defects.
Screening for thalassemia: for pregnant women with obvious anemia during pregnancy, prenatal genetic diagnosis should be performed, which can diagnose heavy beta and alpha thalassemia fetuses in early pregnancy and interrupt the pregnancy in time to avoid the occurrence of fetal edema syndrome and the birth of heavy beta thalassemia patients, which is a proven method to prevent this disease.
How to screen for newborn diseases (congenital hypothyroidism, phenylketonuria)?
After the newborn is born for 3 days and has been adequately fed, the receiving hospital will collect 2 to 3 drops of the newborn’s heel blood on a special filter paper sheet, dry it, seal it and freeze it, and send it to the Newborn Disease Screening Center for testing every week.
If the test result is abnormal, the newborn screening center or the receiving hospital will notify the parents. Parents should promptly take their child to the designated hospital for a follow-up examination and prompt treatment or prevention after the diagnosis is confirmed. Therefore, when a mother is admitted to the hospital for delivery, she should inform the medical staff of her real phone number and address that can be easily contacted so that the newborn disease screening center or the receiving hospital can contact the parents in a timely manner.
When is the best time to treat metabolic disorders in newborns?
Newborns diagnosed with congenital hypothyroidism and phenylketonuria (PKU) are better treated as early as possible, usually within one month of birth. If left untreated, the above-mentioned disorders can affect the growth and development of the child, and in severe cases can lead to mental retardation. Once the damage is done, it is difficult to cure and can cause great suffering to the family.
Parents should be reminded that screening for newborn diseases enables early detection of congenital genetic metabolic diseases and enables early diagnosis and treatment of the majority of children with these diseases. However, due to the individual differences in children and the sensitivity of any screening test can only reach about 95%, so even if the screening results are normal, if the child is found to have abnormalities, he or she should still go to the hospital in time for examination and treatment.
The overall goal of newborn hearing screening is to identify children with hearing impairment early and to provide timely intervention to reduce the impact on language development and other neuropsychiatric development.