What are the calculation methods of IVF pregnancy weeks?
IVF refers to the process of implantation into the mother's uterus after in vitro fertilization through assisted reproductive technology to achieve pregnancy and pregnancy. For IVF, the calculation of pregnancy week is very important, which can help doctors and pregnant mothers understand the development of embryos and predict the expected date of delivery. The following will introduce some commonly used calculation methods of IVF pregnancy week.
Calculation Method of Pregnancy Week Based on Last Menstruation
Last Menstrual Period (LMP) is one of the most commonly used methods to calculate the gestational weeks of test tube infants. This method takes the first day of the last menstrual period as the starting point of the pregnancy week, and then calculates one week every cycle until the current date. With this method, the gestational weeks of IVF can be estimated preliminarily.
For example, if the first day of the last menstrual period is January 1, 2021, and the current date is February 1, 2022, then based on four weeks of each cycle, it can be calculated that the pregnant mother's pregnant week is about 13 months, that is, 39 weeks.
Although the calculation method of pregnancy week based on the last menstrual period is simple and easy, due to the influence of factors such as the length of different women's menstrual cycle and the time difference of fertilization and implantation, there may be some deviation from the actual pregnancy week.
Calculation of gestational age based on ultrasonic measurement
Ultrasonic examination is one of the important methods to judge the embryonic development and gestational age. The gestational age of IVF can be accurately determined by ultrasonic measurement of fetal head hip length, head circumference and other indicators, combined with the development index table.
Usually, the first ultrasonic examination is carried out on the 7-10 days after embryo implantation, and the existence of the embryo can be detected; On the 28th day after embryo implantation, the fetal heart rate of the fetus can be measured by ultrasound, and the gestational week can be calculated by combining the size of the embryo and other indicators; At about 45 days after implantation, fetal organ development can be measured by ultrasound to further confirm the gestational age.
The calculation method of gestational age based on ultrasonic measurement has high accuracy and can reflect the situation of embryonic development and gestational age more truly.
Calculation Method of Pregnancy Week Based on IVF Implantation Date
The date of IVF implantation is an important reference for the calculation of pregnancy week. In the process of IVF implantation, the embryo will be implanted into the mother's uterus on a specific date. According to the implantation date, combined with the menstrual cycle and fertilization date of the pregnant mother, the pregnancy week of IVF can be calculated more accurately.
Generally speaking, test tube babies are checked about 14 days after implantation, pregnancy is confirmed by the concentration of progesterone in the blood, and then pregnancy weeks are calculated based on the implantation date.
The pregnancy week calculation method based on the implantation date of test tube baby can provide more accurate pregnancy week information, but it also needs to be combined with other factors for comprehensive judgment.
Calculation of gestational age based on fetal growth curve
The fetal growth curve is a curve drawn based on a large number of fetal data of normal pregnancy, which can be used to calculate the gestational weeks of test tube babies.
The pregnancy week of test tube baby can be determined by measuring the fetal head hip length, head circumference and other indicators through ultrasonic inspection, and then comparing with the fetal growth curve. Generally, the fetal growth curve is calculated according to the average and standard deviation of normal fetuses at different gestational weeks, which can provide more accurate information about gestational weeks.
To sum up, there are many methods to calculate the pregnancy week of IVF, including based on the last menstruation, ultrasonic measurement, IVF implantation date and fetal growth curve. Choosing appropriate calculation methods can help doctors and pregnant mothers better understand the development of embryos and predict the expected date of delivery, and provide reference for pregnancy management and postpartum care.
Summary
The calculation of IVF pregnancy week is very important for doctors and pregnant mothers. This paper introduces four commonly used methods for calculating IVF gestational week based on the last menstruation, ultrasonic measurement, IVF implantation date and fetal growth curve.
The calculation method of gestational week based on the last menstrual period is simple and feasible, but there may be some errors due to various factors. The calculation method of gestational age based on ultrasonic measurement has high accuracy and can reflect the embryonic development and gestational age. The calculation method of gestational week based on the implantation date of IVF needs to consider other factors comprehensively. The calculation method of gestational age based on fetal growth curve can provide more accurate gestational age information.
Choosing an appropriate method for calculating the gestational week of test tube babies can help doctors and pregnant mothers better understand the development of embryos and predict the expected date of delivery, and provide a reference basis for pregnancy management and postpartum care.
