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.
Hearing or seeing your babyâs tiny heart beating for the first time is an exciting moment. Your baby's heart starts beating when you're six weeks pregnant. Around the time of your dating scan, your babyâs heart is beating between 110 times and 160 times a minute. Thatâs about twice as fast as your heartbeat. You may also hear your babyâs heartbeat at one of your antenatal appointments. Your midwife is unlikely to listen for it while youâre still in your first trimester, as it can be hard to pick up at this stage. After your dating scan, the next time you hear your babyâs heartbeat may be during your 16-week appointment with your midwife.