The first meaning is 'metre' which is a measurement of length. If the 'm' stands alone it is metre. The second meaning is 'milliâ¦' which means a thousandth. In this case 'm' can not stand alone, we need to know what we have a thousandth of; if it is weight, length or some other thing. Example: mg means 'milligram', a thousandth of a gram. Example: mm means 'millimetre', a thousanth of a meter.
At about six weeks into pregnancy (four weeks from conception), you should be able to see your baby's heartbeat on ultrasound. The typical heart rate at this age is about 100 beats per minute.
While the heart rate in pregnancy is faster than an adult's heart rate, the truth is that a normal fetal heart rate changes during the stages of pregnancy. How Your Baby's Heart Rate Changes. At about five weeks gestation, your baby's heart begins to beat. At this point, a normal fetal heart rate is about the same heart rate as the mother's: 80 to 85 beats per minute (bpm). From this point, it will increase its rate about three beats per minute per day during that first month.