Is it too late for 25 weeks for large-scale ovulation? Large-scale ovulation screening is carried out in the pregnancy18 ~ 20 weeks. At this time, the examination has the optimal anatomical performance because of ultrasound, and enough time is reserved for the necessary invasive examination. Fetal heart ultrasound examination is best performed at 22 ~ 24 weeks of pregnancy, that is, when the heart structure is larger. It is best not to exceed 28 weeks for screening for large-scale teratogenesis.
Malformation screening is divided into three ways:
1, blood screening
Including maternal blood test of human chorionic gonadotropin (? -HCG) and pregnancy-associated protein A(PAPP-A) to screen fetal chromosomal aneuploidy and neural tube malformation.
2. Ultrasonic screening
Including the thickness (NT) of the transparent layer behind the neck of the fetus and the examination of the nasal bone of the fetus at114 weeks of pregnancy, to evaluate the chromosomal aneuploidy of the fetus. In addition, there is also a screening for large-scale rejection of pregnancy18 ~ 20 weeks.
3. Invasive operation inspection
Fetal chromosome examination is carried out by villus sampling, which is carried out after 1 1 weeks of pregnancy, and is used to diagnose chromosome and genetic diseases, usually by abdominal puncture.
Precautions for screening for large-scale teratogenesis 1, and don't be too nervous.
Generally, serological abnormality screening (Down's screening) was carried out around11~14 weeks of pregnancy, and the conclusions of low risk and high risk have been reached. Pregnant mothers should calm down their emotions and not be too nervous before screening for large-scale teratogenesis. Excessive stress of pregnant mothers and changes in hormone levels in the body will lead to some corresponding changes in the intrauterine fetus.
2. Make an appointment with a qualified hospital in advance.
Secondly, every region has a fixed prenatal screening institution, and not all hospitals or ultrasound doctors can conduct prenatal screening. Need to go to a qualified hospital for prenatal malformation screening. In particular, ultrasonic inspection requires the professional skills of operators. Due to the busy work in the hospital, it is recommended to make an appointment in advance to avoid missing the best inspection time. This requires knowing one's gestational age and finding out the time for making an appointment in advance in a nearby prenatal screening center.
3. You don't need an empty stomach before the examination, but you should exercise properly.
There is no need for fasting before the examination, if the hunger caused by fasting will affect the results of the examination. Eat properly before the examination to ensure the supply of blood sugar. And appropriate activities, so that the intrauterine fetus appropriate activities, to ensure that there is a fetal posture conducive to examination.
4. The inspection time is about 30 minutes.
The inspection schedule is not fixed, mostly about half an hour. Of course, there will be some increase or decrease according to everyone's situation.
Wonderful recommendation:
ectopic pregnancy
amniocentesis
Four-dimensional color Doppler ultrasound
down syndrome screening
phlebeurysma