pre-natal scans

Pre-natal scans

Pregnancy scans can be very exciting as they show the first glimpse of your growing baby. Here are your pre-natal ultrasound options.

Going for the first antenatal scan is one of the highlights of pregnancy for a woman who is expecting. An ultrasound scan, also known as a sonogram, is a procedure that uses high frequency sound waves to create an image of part of the inside of the body. A small handheld sensor called a transducer is used to direct ultrasound waves at your body. When the sound waves hit an object, such as the womb, they bounce back as an echo.
At your scan, you will be asked to loosen your clothing from around your abdomen and lie on a couch so that the midwife or doctor can apply gel to your abdomen. The transducor is then placed on your abdomen and moved around to produce pictures. The gel can be easily wiped off afterwards. These ultrasound echoes are then converted into an image by a computer.
The number of scans you have depends on whether your pregnancy is considered high or low risk. For example, if you have had previous complications in a pregnancy, suffer from high blood pressure, or are expecting twins – you might be offered more scans to keep an eye on your baby’s growth and health.

Early pregnancy scans

If you have an early pregnancy scan (from six weeks to 10 weeks), it is more likely to be a transvaginal scan. A scanning device is inserted into the vagina – some women might feel a bit of discomfort but it should not cause any pain. This type of scan allows the ultrasound to get closer to the embryo or fetus, which can give a more detailed result than a transabdominal scan in early pregnancy. These scans are generally used to if there is a question about whether the mother has suffered a miscarriage, or if the pregnancy is ectopic (contained in the fallopian tube).

First trimester scan

As part of your antenatal care, your midwife will offer you a dating scan that will give you a date for the birth of your baby. This scan will not be able to determine what gender your baby is at this early point, but it will identify if there is just one baby in there and will confirm if your pregnancy is viable. This scan, which normally takes place between 10 and 13 weeks, will also:

  • check that your baby’s heart is beating and that he’s developing normally
  • check for any abnormalities
  • check that the pregnancy is situated in the womb
  • check whether the age of the baby agrees with your own dates

The anomaly scan

This scan is normally done at the 18-22 week stage and will examine your baby’s organs, take measurements of limb lengths and stomach and head circumference. These scans, however, are not routine in many maternity units in Ireland. If you want to know your baby’s gender, this can usually be seen at this scan – although the sonographer will not tell you the sex of your baby unless you ask. But if your baby’s lying in an awkward position, it’s not always easy to tell. It’s worth remembering that the main objective of this scan is to check that your baby is developing normally, rather than whether you’re expecting a boy or girl.
Sonographers will be looking out for a list of conditions. Detecting any abnormalites can allow doctors and parents to plan and prepare for various outcomes.
The position of your placenta will also be checked. If it is found to be lying low in your uterus, you will have another scan in the third trimester to check its position, but by then the placenta will probably have moved away from your cervix.

3D and 4D scans

What benefits do 3D and 4D scans offer over the normal scans that a pregnant lady is offered in a maternity hospital?
The 3D/4D baby scans gives you a unique opportunity to see what your unborn baby is up to during pregnancy. Time is taken to capture 3D images and 4D video clips – the fourth dimension is the moving part.
From 25 weeks onwards, the face of your baby becomes very clear and features can be identified in three dimension. This is a great bonding experience – especially for the dads.
Some of the things we have witnessed on 3d4d scans include babies yawning, drinking, smiling, sucking their thumbs, putting their feet or umbilical cords into there mouths, opening their eyes and even pulling grumpy faces!

Are 3D and 4D pre-natal scans useful for spotting potential problems with a baby’s development in the womb?

3D/4D imaging shows the surface of the baby and not the internal organs. They can be useful for assessing some anomalies such as facial defects like cleft lip, open spina bifida, clubbed feet etc. but they are not typically diagnostic scans. 2D (black and white) scans see straight through the baby, allowing the sonographer to examine the internal organs. Most anomalies affect the internal organs, so the 2D scan will remain the gold standard in fetal imaging.
The Ultrasound Suite in Bray and Grafton Street is one of the few centres that provide a 2D well-being baby scan in conjunction with your 3D/4D baby scan all for one reasonable price, as they believe that the health of the baby is of utmost importance.

What stage of pregnancy is the best time for a woman to have a 3D or 4D scan?

These scans can be performed from 12 weeks onwards. The images become clearer and more realistic as the pregnancy goes on. It is important to have enough fluid around the baby and for the baby to be big enough to produce realistic images. 30 weeks gestation is the optimal time to get the scan done.
Some patients are too excited to wait that long, so they have a mini 3D/4D scan at about 18 weeks (when the gender can be seen too) and another mini 3D/4D scan at 30 weeks.

Deborah Sudding
Clinical Specialist Sonographer
The Ultrasound Suite

More like this:

Antenatal scans
Maternity options in Ireland
5 things you need to know about pregnancy

Ask Tracey

Midwife Tracey Donegan answers your questions about pregnancy and birth

Q When should I have my first pregnancy scan? And how many scans should I get throughout my pregnancy?

Your first scan is known as your dating scan and is routine in all hospitals. Most mums will have this scan at their booking visit, which can be anywhere between 12-18 weeks. The earlier the scan the more accurate it will be. If you have experienced recurrent miscarriages some hospitals will scan you earlier. Contact your antenatal clinic for more information. In Ireland, most women will have two scans in a healthy pregnancy – a dating scan and an anomaly scan at around 20 weeks. However, some units provide a dating scan only. Private scans are also available in most cities and many parents use these services for additional reassurance and to find out the sex of their baby.


Ask Allison

Q My sister-in-law and I both work three-day weeks and we help each
other out with child minding on our working days, which up until recently has worked out really well. Between us, our kids are aged between five and nine years – the problem is that it’s now become quite apparent that we have very different parenting styles. I prefer my two daughters (seven and nine) to have a structured day. For example, in my house, we have allocated times for television and iPads, etc. My sister-in-law, however, lets the kids run loose after school – homework is ignored and my kids end up wired after eating sugary treats all afternoon. I am considering looking at after-school childcare for the kids, but I’m worried that this is going to cause a family argument. Is there a diplomatic way that I can ask my sister-in-law to introduce some discipline into her child-minding days? It certainly doesn’t do her two kids any harm when I am minding them in my own house!

In a word, no, there is no diplomatic way to do this as it may very likely seem like your saying that your parenting style is better than
hers. As L’Óreal says, ‘now here comes the science bit.’ Dr. Kaylene
Henderson, a child psychiatrist, wrote a very interesting blog about ‘the
science behind the Mummy Wars’. She explains that before she had
children of her own she hadn’t been aware of how parents have a
very specific sense of the right parenting style. She also found that parents could be very definite in defending their chosen parenting style. Dr. Henderson, who describes herself as a curious, scientific, open-minded person, was surprised at how defensive parents could be and, at times, of their judgemental attitude towards each other. She explained the neurology of the Mummy Wars; okay, I’ll need you to bear with me for a second. Warning; I’m about to use some neuro-techie language.

Why do we judge each other?
As we have all had different experiences, this means that we all have very different memories stored in our brains. Most of our memories are ‘explicit’ memories – these are ones that we can recall easily such as important dates that mean something to us; important birthdays, special events or stories of and about our lives.
There is another type of memory called ‘implicit’ memory that plays a
key role in our parenting. This type of memory is the stuff that you do on autopilot. Psychologists call these heuristics or rules of thumb –
such as tying your shoelace, or driving your car (once you have learnt
to do both first!). Otherwise we’d really waste a huge amount of time
pondering over tasks that we have readily available to us. This seems to be where the science bit of our parenting style kicks in. This implicit memory goes all the way back to when you were an infant being parented by your parents. This is when you started the process of storing up how they did it into your memories.
Unless you make a conscious choice and effort to parent differently, what you saw and unconsciously learnt will be your automatic go-to parenting style.

We learn habits
This can really kick into gear when we feel our parenting style is
being mirrored or highlighted by disapproval from another parent. I know the cold sweat you feel when your child decides to make their outstanding bad behaviour performance at, of course, the most public and worst time. The implicit autopilot of how your parents dealt with these outbursts will flow unconsciously from you if you haven’t worked super hard to be aware and consciously change the old habits.
What’s happening for the on-looking parent is that they see you doing something they are used to doing, but you are doing it all wrong. Simply, because that is not how they know how to do it.

Find a way that works
You both have different parenting styles – who is to say which type is correct? You just need to know what works best for your family and that’s the bottom line. The irksome feelings won’t go away. You can talk to your sister-in-law, but I’m adding a caveat that it would be hard not to hurt her feelings. What we’re possibly looking at is that you prefer a more structured form of parenting, whereas your sister-in-law has a more permissive style. I’m not sure the two styles can mix, the mixture is a bit like oil and water.
If a collaborative shared form of parenting style can be agreed upon, then that is great, but our learnt hardwiring may prove difficult to change despite the intent to do so.
Perhaps, your own instinct of changing childcare might work best for you. In terms of making childcare work; the fit is ultimately the most
important aspect as you want a cohesive congruent feeling of the other caregiver to just ‘getting it’, like in any good partnership. Best of luck
with this and I wish you both well.