The time of pregnancy can be estimated by various methods such as the time of the last menstrual period, abdominal ultrasound, ovulation test paper or the time of embryo transfer.
1. For women who have regular menstruation, the time of pregnancy is counted from the first day of the last menstrual period.
2. For women with irregular menstruation, the time of pregnancy can be roughly estimated by abdominal ultrasound of the embryo development.
3. For women who have ovulation monitoring or assisted reproduction, the time of pregnancy can be estimated by ovulation test paper.
4. For women with assisted reproduction, pregnancy time is usually calculated from two weeks before the date of embryo transfer.
There are various methods of calculating the time of pregnancy, and the results of various methods vary to some extent, so it is recommended to choose the appropriate projection method according to the situation.