Is a dating scan accurate? The scan's main purpose is to work out accurately how many weeks pregnant you are and estimate your due date. You may have calculated the length of your pregnancy from the first day of your last menstrual period LMP. This is even though you don't actually conceive until 14 days after your LMP, or later than this if your cycle is longer than 28 days.
You probably know when your LMP was, but not when you actually conceived. If you do know the conception date, this is counted as day 14, and not day one. If you have an irregular cycle, or if you've recently been taking the contraceptive pill , working out the date from your LMP isn't a very accurate method. Scans are more accurate Bottomley et al If the scan date differs from your period dates, the scan date will be used.
The scan date is usually later than the period date, so accurate dating reduces the number of women having labour induced because their babies are thought to be overdue LeFevre et al , NICE What else will the dating scan reveal? The scan can check that your baby has a heartbeat and is developing normally. Your baby's head, limbs, hands and feet, and some organs can be seen. Looking for abnormalities isn't the purpose of this scan, though.
That's the job of your next routine scan at about 20 weeks , when more detail can be seen as your baby grows bigger. However, some major problems can be seen at your dating scan, such as problems with your abdominal wall or with your baby's skull. You may need a second scan to check the first scan's findings. The dating scan will also show if you're expecting twins, triplets or more. It's helpful to know about twins early on, as it's easier to see whether or not they share a placenta.
Finding out about having twins early in pregnancy also gives you more time to prepare for the birth and for your doctor or midwife to plan your care. Knowing about twins early is also useful if you want to have screening for Down syndrome. This is because blood tests for Down syndrome are not very accurate if you are having more than one baby. Most women would not be offered this scan but if your doctor has referred you for a scan it will be covered by Medicare.
It's natural to feel a little anxious about having a vaginal scan. If you do feel anxious, you should discuss it with the nurse or sonographer beforehand. It's also a good idea to take someone along with you. If it helps, you could also ask for a woman to carry out the scan. The vaginal scan will give a clearer picture of your baby earlier in pregnancy than an abdominal scan.
See our overview of scans to find out more about how vaginal scans are done. Dating scan This scan is also a more accurate way of establishing your due date than counting from your last monthly period LMP. Many pregnant women are not sure of the date of their last monthly period LMP and so a dating scan might be recommended to work out an accurate due date. Finding out how pregnant you are is important to ensure that the results of your nuchal translucency scan are accurate.
It can also find out if you are having more than one baby. Nuchal translucency scan You will be offered a nuchal translucency scan between 11 and 13 weeks and 6 days of pregnancy. If you are going to have your baby in a public hospital you may be able to have this scan at a public ultrasound clinic. In many cases you will have to pay for this scan and test in a private centre. What happens during an ultrasound scan? Ultrasound scans are painless but the gel used within the examination can feel a little cold and you may feel a little discomfort when the ultrasound probe presses on your tummy if you have a very full bladder.
An ultrasound scan typcally takes approximately 10 minutes to complete and the images seen will determine whether a Trans-Vaginal ultrasound scan internal is needed. Your ultrasound scan will be carried out by one of our highly qualified professionals in a caring and comfortable environment. During your scan we will explain the findings to you and following your scan we will give you your images and detailed report.
If we cannot see a heartbeat then this is either due to the pregnancy being too early this is the commonest reason or that the pregnancy is found to be not viable. From this measurement we can work out how many weeks and days preganant you are this early measurement is approximate for dating. At this stage often the baby can be seen making small movements usually past 8 weeks which are amazing to see.
The sonographer will put ultrasound gel on your tummy and tuck tissue paper around your clothing to protect it from the gel. When will scans be offered. Having a dating guys in the army in pregnancy is usually a dc singles dating services event, but the sonographer may need to apply slight pressure to get the best views of the baby, but the sonographer may need to apply slight pressure to get the best views of the baby. The dating scan and anomaly scan are offered to all women, you may be offered further tests that have a firdt of miscarriage. How long will a scan take. Most scans are carried out by specially trained staff called sonographers. Please ask you virst about date of first scan in pregnancy before your appointment. The scans are completely painless, sonographers need to keep the screen in a position that ptegnancy them a good view of the baby - either directly facing them or at an angle, and your antenatal care will continue as normal! You'll be given the chance to discuss it with your maternity team before making your decision. You'll be given the chance to discuss it with your maternity team before making your decision. This is because sfan babies are healthy and date of first scan in pregnancy not have abnormalities.