You delayed fo 4 days but before that you have do a test of pregnancy then it might be positive how could know many weeks your beybi?

To determine how many weeks along you are in your pregnancy, you can use a pregnancy calculator. This tool takes into account the date of your last menstrual period (LMP) and estimates your due date based on a typical 28-day menstrual cycle. If your cycle is longer or shorter than 28 days, you may need to adjust the calculation accordingly.

Here's how to use a pregnancy calculator:

1. Enter the first day of your last menstrual period.

2. Select the length of your menstrual cycle in days.

3. The calculator will estimate your due date and the number of weeks you are pregnant.

It's important to note that pregnancy calculators are not 100% accurate, and your actual due date may vary by a few days. If you are unsure about your due date, you can talk to your doctor or midwife for a more accurate estimate.

In addition to using a pregnancy calculator, there are a few other ways to estimate how far along you are in your pregnancy:

1. Ultrasound: An ultrasound is a medical imaging procedure that can provide a more accurate estimate of your pregnancy's gestational age. During an ultrasound, a sound wave probe is used to create images of your uterus and the developing baby.

2. Fetal heart rate: The fetal heart rate can also be used to estimate gestational age. A normal fetal heart rate ranges from 120 to 160 beats per minute (bpm) in early pregnancy and slows down to around 110 to 150 bpm by the end of pregnancy.

3. Fundal height: The fundal height is the measurement from the top of your pubic bone to the top of your uterus. This measurement can be used to estimate gestational age by comparing it to a chart of average fundal heights for each week of pregnancy.

4. Blood tests: Certain blood tests, such as the human chorionic gonadotropin (hCG) test, can be used to confirm pregnancy and estimate gestational age.

If you are unsure about how far along you are in your pregnancy, it's a good idea to talk to your doctor or midwife. They can help you determine your gestational age and provide you with information about the next steps in your pregnancy.