Pregnancy: our first pregnancy scare. Understanding a hospital monitor for my 32-week pregnant mother.

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Learning about the ‘scary’ numbers on the hospital monitor and what they mean for my wife: a mother-to-be and our baby.

I’m sure I’m not the only one. This week my wife and I went to emergency as my wife, Jenna had just gone to her regular midwife check-up. She discovered that our son had a higher-than-normal heart rate.

In our case, he was sitting between 165 – 190 bpm. And the bpm considered doing so for the entire appointment.

They consider the normal/average heart rate of a fetus to be between 110 – 160 bpm (beats per minute).

Jen called on her way home, and naturally, the “action man” stepped into… well, stress. But the midwife said, not to worry but go to the hospital to be monitored. So we did. Unlike me, Jenna of course was not stressed. Kudos to her!

After presenting to ER and being taken through to the pregnancy wing, she was hooked up to a monitoring machine to observe both the mother and baby’s clinical observations. Or “obs” for short (there’s a lot of lingo in the medical profession). This machine is called a cardiotocograph or CTG (electronic fetal monitor) which is used to identify any fetal distress. I love modern medical technology!

Now, if you’re unfamiliar with these machines, they can seem quite daunting. It’s an unfamiliar world. And finding out exactly what all these numbers and graphs mean can be a bit difficult but I suggest asking your nurse or doctor to explain it to you.

For us, Jenna was being monitored to observe the ongoing heart rate of our little man. This went on for about an hour. This was to better identify if there was an ongoing issue with his high rate or if it will settle over that time.

The CTG Fetal Monitor (Cardiotocograph)

Let’s review the numbers on this monitor below so you too will be able to read them. And just so you know in a past life I was a nurse. I worked in aged care and in different hospitals around the city, so I have some professional insight into how to reach these machines.

Let’s start with the blue smaller numbers.

Sp02

Sp02 stands for Oxygen saturation and measures how much oxygen your blood is carrying as a percentage of the maximum it could carry. Generally speaking, a healthy person’s oxygen sats should be over 95% and closer to the 99% mark.

And as you can see… Jen at the time of this photo was sitting perfectly.

Pulse

Pulse stands for heart rate. Most of us have heard of this reading. A resting healthy range is usually between 60 – 100 for adults. But this will vary depending on the fitness of the person or if they’re carrying a 32-week-old baby.

Pre-pregnancy Jenna was closer to 60-70 bpm but as all pregnant women will tell you, that short brisk walk might as well be a climb to Mount Everest. So naturally, being 32 weeks pregnant, her bpm will be higher. This is no cause for concern.

FHR1

FHR1 stands for Fetal Hear Rate and is measuring the baby’s heart rate. It is doing this via the sensors strapped onto the mother’s abdomen (as you can see in the first photo). What is considered a normal heart rate for a fetus is between 100 – 160 bpm. And as you now know, this is what led us to the ER as our little guy was not lowering past 165 bpm.

TOCO

The final reading in green, which to be honest, I was not familiar with as I haven’t worked in pediatrics or birthing wards. The TOCO measurement relates to contractions. It measures the pressure that relates to, well, essentially how far along the mother is into labor. Yeah, I didn’t know that was a thing but TOCO stands for tocodynamometer (toh-koh-dahy-nuh-mom-i-ter)… not sure that helped me pronounce it but numbers are displayed by a unit called mmHg. This stands for millimeters of mercury and measures the tension of the abdominal wall. As labor progresses, the pressure gets higher, and the contractions get longer, harder, and stronger and we see an increase in the TOCO number.

Thankfully, the reading was 11 mmHg for us… so no labor this round. He’s just doing some fakies.

There’s a lot more you can learn on this alone and there are plenty of resources out there but the very basics are:

The TOCO measurement range is between 0 to 100 mmHg.

Braxton Hicks Contractions	5-25 mmHg	All is good but the baby is faking their birth day. You could be dehydrated which is leading to the reading.
Latent Phase Contractions	25-40 mmHg	It’s the pre-start. Could last for hours or even days. Sorry, ladies. “Mild contractions” can be felt
Active Phase Contractions	50-70 mmHg	Now it’s started. Strong contractions and the mother’s body is in preparation.
Transition Phase Contractions	80-100 mmHg	At 100 the mother is fully pushing. It’s on! No returns or take backs.

What we learnt from this experience.

The midwife did ask Jenna if she had eaten and drunk much that day and suggested she might have been a little overwhelmed with going to the appointment. Understandable.

We think it was a lack of water as they say the Braxton (5-25 mmHg) reading can indicate the mother is dehydrated and so should drink some fluids.

She did while on the monitor and the heart rate of our little man did decrease as you can see in the photos.

We also noted that it’s now time for her to slow down more. But if you’re a self-employed photographer like her, you’ve booked several gigs four weeks leading up to the due date… as ~~you~~ she does.

I’ll keep you updated.