Fetal movements - how much is enough?

If you’ve ever come to see me when you’re pregnant you will agree that my line of questioning during your visits is predictable.

“Are you well?”

“How’s the baby moving?”

“Any swelling in your feet or hands?”

Every single time you will get those same questions, usually in that order and whilst I do listen to all of your responses during our consultation, it’s the answer to that middle question that I’m arguably most interested in.

The way that it is answered will determine what will happen for the rest of the visit. If the answer is “Yeah good” or “Fine” or “The same as usual” or “ Oh my goodness, it’s like there’s an octopus in there” – I will be happy that your baby is probably just fine. Some women will stress when their baby is moving lots – I think sometimes they worry that the baby is somehow stressed and is wanting to get out. The truth is quite the opposite – a baby that is squirming all over the place is getting plenty of everything that it needs.

If the answer indicates that there have been significantly less movements my ears will prick up. I may not show it but that sort of answer always makes me at least a little concerned that this is a baby that is not happy.

There are many reasons why babies don’t move so much. They go through sleep phases. Sometimes their Mums have taken medications that make the babies sleepier and less active. Sometimes the fluid around the baby is increased or decreased. Sometimes the placenta is on the front wall of the uterus and the movements are not as easily felt. If the Mum is overweight the movements are less easily felt. Probably one of the commonest reasons that the movements are not felt is because the mum is distracted either by work or more commonly racing after an older child. Babies move more in the evenings than during the morning. There's lots of variables.

One of the biggest fears with decreased movements is that the baby is not moving well because it’s not getting enough oxygen and nutrition. It’s not lying back because it’s decided to just “chill out” for a while. It’s lying still because it just doesn’t have the energy to move.

I will always take the tact of wanting to prove that the reduction of movements is NOT due to a compromised baby. If the baby is compromised, then my job is to deliver that baby in as good a condition as possible. Sometimes that means a caesarean. Sometimes that means an induction. ALWAYS, it means keeping a very close watch on that baby until it is out of your body. If the baby is very premature when problems are detected it may mean monitoring the baby exceptionally carefully until it has matured to the point where it can be delivered safely and have the best chance of making it in the outside world.

The $64,000 question is – “How many movements are enough?”.

The $64,000,000 answer is – no-one really knows. Helpful - huh!

One of the more common methods for counting movements is the Cardiff “Count to Ten” method. Pick a time of the day when baby is most active. Start counting. When you get to ten movements – you’re done – baby is happy. If you’re still counting 10 hours later and you’re not up to ten movements – ring your maternity unit. Most women will get to ten movements waaaayyyyyyy before 10 hours.

It is now recognised that probably the best way to determine how many movements is enough is by allowing the mother to subjectively note any change in movements. That baby has been inside of her – you – for months. You know what your baby’s pattern of movements are. You know how much is enough for YOUR baby. Having said that, obstetricians aren’t going to go around inducing every second woman because she says there has been a reduction in her movements. However, it will make them take extra care to ensure that they are satisfied that your baby is better off inside rather than outside.

So how do we do that? – look at the well-being of the baby.

As a resident (just over 20 years ago) one of the best tools that we had for determining if your baby was “happy” or “stressed” was to measure it’s heart rate over a period of time. The resulting trace, a squiggly line meandering along a sheet of paper would give us some degree of comfort that your baby was fine. This test is called the cardiotocograph (CTG). The top line measures the baby’s heart rate (cardio) and bottom rate indicates whether any uterine contractions are present (toco). Most CTG’s also give an indication of whether foetal movements have been picked up by the CTG.

In this normal CTG the fetal heart rate is the squiggly line at the top. Fetal movements are seen as dots. There are no uterine contractions and so the line at the bottom is flat.

This test in the overall scheme of things is crude. It is the equivalent of putting an adult in a box and allowing them to stick their arm out of a hole in the box in order for the doctor to assess their pulse. The trick would be to then figure out if the patient was healthy based purely on their pulse rate.

We are a little more sophisticated these days. We are now able to use ultrasound to measure how big the baby is, or more importantly how small it is. We can also measure the amount of fluid around the baby - if there's less than can be a sign that the baby is not getting enough nutrition. We can look at the blood flow through the umbilical cord and numerous other blood vessels in the baby. All of this gives us far more detailed information about the well-being of the baby. In particular, is that baby getting enough oxygen to it’s brain and heart. With babies that are struggling at very early gestations it is the monitoring of the blood flows that will ultimately guide us to when it’s better for that baby to be delivered. When the baby is close to its due date – it’s a no brainer that if the baby is struggling then it should be born. However, when struggling babies are close to the thresholds of survival due to prematurity then we need to try and keep the baby in as long as possible without putting it at risk of stillbirth. With newer sophisticated ultrasound machines to give us the numbers and researchers continually giving us more information to guide delivery protocols we get it right most of the time. Very occasionally however, some babies succumb before they can be given a chance on the outside world.

The take home message is this – if you’re worried that your baby is not moving as much as usual – RING!

Ring your obstetrician’s rooms or ring the maternity unit of the hospital that you’re going to. A lot of patients don’t want to do this – they think they might be wasting peoples time. They think the midwife will be on the other end of the phone line rolling their eyes and whispering to their workmates (with the hand over the receiver) “We’ve got a live one here!” This does not happen!!! Do not hesitate. Ring and get checked out – for you and your baby’s sake. All this technology can only be used if you let us know there is a problem in the first place.