How to calculate the pregnancy week of test tube baby most accurately?
IVF refers to an infant who develops by culturing a fertilized egg to an appropriate stage of development in the laboratory through assisted reproductive technology and then transplanting it into the mother's uterus. The accurate calculation of pregnancy week is crucial to ensure the smooth progress of pregnancy and the health of mother and baby. The accurate calculation method of IVF pregnancy week will be described from the aspects of ultrasonic examination, development of fertilized eggs, embryo transfer and pregnancy test.
Ultrasonic inspection
Ultrasonic examination is a non-invasive technology, which can transmit high-frequency sound waves into the human body through the probe, and observe the development of the fetus through the echo generated image. In the process of IVF, routine ultrasound examination can provide pregnant women and doctors with detailed fetal growth information.
The first ultrasonic examination is usually carried out in the sixth to eighth weeks of pregnancy. At this stage, the fetal heart activity can be observed to confirm whether the pregnancy is normal. Thereafter, ultrasonic examination shall be carried out every 4-6 weeks to observe the development, size, organ structure and amniotic fluid volume of the fetus.
By measuring the fetal head to hip length (CRL), doctors can accurately calculate the gestational age, which is one of the most common calculation methods. However, if ultrasound is performed at a later stage of pregnancy, other parameters such as head circumference and abdominal circumference will also be used to calculate the gestational age.
Zygotic development
The date of IVF fertilized eggs implantation is usually regarded as the beginning of the pregnancy week. The development of the fertilized egg is divided into different stages, starting from fertilization. In the process of IVF, the fertilized eggs are usually cultured in the culture dish until the third or fifth day, and then transferred to the mother's uterus.
Once the fertilized egg is transferred, the doctor will usually take the days after transplantation as the beginning of the pregnancy week. For example, the fifth day after the fertilized egg is transferred means the pregnancy week is five weeks.
This calculation method is commonly used in the process of IVF, because it provides a clear understanding of the development of the fertilized egg, and more directly reflects the interaction between the fertilized egg and the maternal uterine environment.
embryo transfer
Embryo transfer is one of the key steps in the process of IVF. The transfer of embryos depends on the development of the fertilized egg, usually on the third to fifth days after fertilization. Before transplantation, the doctor will evaluate the quality and development of the embryo.
Doctors usually recommend that embryos be transferred to the appropriate developmental stage to improve the success rate. Once the embryo transfer is completed, pregnant women usually need to wait for 10-14 days, and then have a pregnancy test.
Pregnancy test
The pregnancy test is the last method to confirm the gestational age during IVF. It is usually carried out 10-14 days after transplantation, and pregnancy can be determined by detecting progesterone in blood or urine.
Once the pregnancy test is positive, the doctor can calculate the gestational week according to the date of fertilized egg transfer and progesterone level. Although this method can not provide the specific development of the fetus, it is one of the important reference indicators in the calculation of gestational age.
By means of ultrasonic examination, development of fertilized eggs, embryo transfer and pregnancy test, the pregnancy week of IVF can be calculated most accurately. These methods provide doctors with comprehensive fetal development information, help pregnant women and doctors monitor the progress of pregnancy, and provide a basis for the implementation of appropriate medical care and intervention.
In general, the gestational week of IVF can be calculated most accurately through multiple methods such as ultrasonic examination, development of fertilized eggs, embryo transfer and pregnancy test. This will help ensure the smooth progress of pregnancy and provide the best guarantee for the health of mothers and babies.
