A beta hcg is a blood test given in early pregnancy to measure the quantity or amount of hcg, the pregnancy hormone. This test can be done as early as a week after ovulation, even before a positive hpt. The result or number of hcg detected will vary from woman to woman and pregnancy to pregnancy.
Assuming you mean "first Month" the answer is yes. With a very sensitive pregnancy test some pregnancies can be detected as early as 3 weeks and 2 days; this is the first month of pregnancy. Most pregnancies are easily detected at 4 weeks on the day of your missed period with a early pregnancy test this would technically be the beginning of your second month.
it takes five minutes fot pregnancy to be detected at home
Placenta previa can be detected during an ultra sound, but it is normal to have low-lying placenta early in pregnancy.
Most doctors will not see you before 8 weeks, so there may be some evidence by then.
Although the heart is beating, it is unusual to actually detect it this early. 8 weeks is a more common time for it to be detected, depending on your doctor's equipment.
As early as birth
If the blood test is done too early in the pregnancy, the pregnancy won't be detected. If the blood test was done by a doctor, then he/she knows to do it and obtain an accurate result.
No, it can be detected when you miss your first period.