sMater | Dr Jolene Ng | Asthma in Pregnancy

In this episode of sMater, we speak with Mater Hospital Brisbane obstetric medicine fellow Dr Jolene Ng about asthma during pregnancy.

With Australia having one of the highest rates of asthma in the world, Jolene explains the impact of this condition on mum and baby during pregnancy and the importance of managing symptoms.

References: Asthma in Pregnancy Toolkit - Asthma in Pregnancy Toolkit

GP Education activity log:
  Podcast title - sMater: Asthma in Pregnancy
  Provider - Mater Misericordiae Ltd
  Date published - November 29, 2024
  Certificate of completion - click here

To learn more about Mater, visit https://www.mater.org.au/

Transcript

Hello and welcome to this episode of sMater. A podcast by clinicians for clinicians brought to you by Mater, an Australian leader in healthcare for more than a century. My name is Jillian Whiting and we're coming to you from Meanjin the land on which this podcast is being recorded. Hello I'm Maggie Robin, Community GP rural GP obstetrician at Beaudesert Hospital and coordinator of Mater's GP shared care education program.

In this episode we're talking about asthma during pregnancy with Dr Jolene Ng. Jolene is the current obstetric medicine fellow at Mater Hospital Brisbane and also has a background in renal medicine. She's joining us to talk about asthma during pregnancy.

We are Mater. We are Mater. We are Mater. This is sMater. 

Hi Jolene. Welcome to sMater. Thank you for having me here today.

Now the statistics tell us around 2.8 million Australians or 11% of the population are living with asthma which is among the highest rates in the world and we know it's a problem but why is it important to be talking about asthma during pregnancy? Asthma really works with pregnancy both ways so a good control of asthma can really help with the pregnancy but poor control of asthma as well can affect the pregnancy in very bad ways and likewise the pregnancy itself can affect one's asthma control. So having good asthma control really does help with mum's overall quality of life and overall perinatal outcomes as well so it's really important for us to talk about this today.

Why does it asthma worsen during pregnancy?

Look I think firstly there are lots of physiological and I guess normal pregnancy changes. So firstly with the uterus or the uterus becoming more distended that pushes up against your diaphragms and once again again that causes a lot of physiological changes from a functional reserve point of view. Next I guess there are a lot of hormonal changes as well and that can impact on your upper respiratory airways and that affects the sort of mucosal production swelling and edema and that can sometimes worsen one's lung function and lung reserve as well and I think lastly in some patients with a specific immune phenotype in pregnancy the immune system can be altered in different ways and that can also impact the immune fetal type of asthma in in a different way as well so I think there's lots of reasons that the asthma control might change in one's pregnancy.

Are there particular hormonal aspects of pregnancy that we know might worsen asthma?

Yeah so I think the main hormone that comes into play is 
the progesterone hormone that usually rises from very early pregnancy up till second and third trimester of pregnancy and that really is a potent driver of our respiratory centre and what that does it is it can affect our respiratory drive and the sensation of how one perceives breathlessness especially in pregnancy. Other sort of hormones or prostaglandins can also
be responsible in bronchial constriction which is tightening of one's airways which sometimes can worsen asthma control if it hasn't been controlled very well pre-pregnancy so I think those are the two main aspects in terms of hormone changes.

We've looked at how pregnancy affects asthma what about how asthma affects pregnancy?

So if we know that asthma is well controlled it should be okay but what about when it's not well controlled?

What's the impact of that on mother and baby?

Yeah so I think firstly going back to preconception, I think poor control of asthma can really affect someone's quality of life and I guess ability to conceive or in a natural healthy way but during pregnancy we know that poor control of asthma can really sort of impact growth and progression of pregnancy in many ways and I think that really comes down to inflammation overall so really inflammation is bad for pregnancy and bad for the fetus and we know that through many studies pregnancy outcomes or important ones such as fetal weight ongoing uncontrolled inflammation often affects pregnancy outcomes and we do see patients with uncontrolled asthma with prematurity,  a lower fetal weight, overall a higher risk of preeclampsia as well as a higher risk of gestational diabetes which are outcomes we'd like to avoid in a healthy pregnancy.

Australia has one of the highest rates of asthma in the world at 10% however in the Indigenous Community this rate rises to 18% of women and 13% of men. Furthermore a study first published in 2022 in the International Journal of Gynecology and Obstetrics assess maternal asthma experienced by Indigenous women. 
It determined it was associated with an increased risk of emergency caesarian sections, placental abruptions and threatened pre-term labor.

So we know medication can be critical in keeping asthma controlled. If someone comes to see us perhaps in early pregnancy, are there particular medications we need to avoid or important ones that we need to continue?

I usually say the general rule applies to a non-pregnant woman as well as woman with asthma in pregnancy so I wouldn't necessarily change any of her usual medications. So that applies to both the preventers the maintenance therapy as well as treatment required in an acute exacerbation. So firstly from a puffer point of view an inhalers point of view if they're already established on a  
short acting beta-adrenergic agonist I would probably continue that it's safe as well as any inhaled corticosteroids or longer acting beta-adrenergic agonist. Those are as validated and safe in pregnancy as well so I would absolutely continue all of those if someone has a flare or an exacerbation during a pregnancy and they do require steroid therapy. A woman should be provided with the similar treatment as well as if she was not pregnant I guess moving on to I guess more advanced therapy so some women could be already established on things like leukotriene receptor antagonist such as Montelukast or Zileuton and I think and if they are well established and well controlled on those therapies there's no reason to change them and then moving on to the more sort of advanced or biologic therapies in asthma I think that should be reviewed once again on a case by case basis and also in consultation with the respiratory physician.

Are there any medications that have to be avoided?

Yes so I think the main one would be Labetalol which is a beta blocker and that's commonly used in hypertension or gestational hypertension in pregnancy so it shows that it can worsen any sort of underlying broncho spasm so I would try to avoid that.

And how often should they be seeing their GP or their doctor if they have severe asthma?

Yeah so I think the general sort of national asthma council recommends in a non-pregnant person to be reviewed every 3 months but I think in a pregnant woman I would probably recommend to review their asthma control review their maintenance therapy on a monthly basis just to make sure that things haven't changed. You mentioned that we shouldn't feel wary of starting someone on oral steroids for an exacerbation of asthma, what about if they end up needing steroids for a longer period? Is there anything we should be concerned about?

Yeah I guess it depends on firstly the gestation. If they're very early in the first trimester there's a small 
slight increased risk in things like cleft pallet as well as prematurity and fetal weight but you know not so much in the second and third trimester but I guess the sort of overarching principle with steroids on a sort of medium or longer term basis would be mainly to look out for gestational diabetes especially in in doses say above 30 milligrams for more than one or two weeks. I think that's some that's probably a starting point where we would probably recommend regular home blood sugar finger prick testing monitoring just to make sure we're not missing a diagnosis of GDM or steroid induced diabetes here. What are your thoughts about non-pharmacological strategies? Is there anything that you think would be helpful in this case?

Yeah absolutely. So I think that's really quite important and even more important than the pharmacological therapy sometimes so once again I think preconception counseling and education really is very important.
So women before even falling pregnant they should be quite aware that good asthma control is absolutely necessary. Remaining adherent to their current therapy and also making sure that everything's up to date and being renewed so that's really important. Moving on I think prevention is really important so once again the annual flu vaccine as well as avoiding any triggers that they're quite used to outside of pregnancy so anything like dust or fur or anything that may trigger the asthma they should just have a bit of a higher awareness to avoid those things.

What approach do you take for smokers then?

Yeah look I think we've got to be quite, it's a difficult topic and I think we have to come in with the assumption that most women want the best for their pregnancy and that smoking reduction or sociation is not the easiest thing so I think we should come in with a more encouraging sort of approach and try to link them in with as as many resources as we can possibly provide and always just try to encourage even reduction of the smoking and avoidance of triggers that might prompt them to smoke more and always try to encourage smoking sensation as well as vaping. 
I think most importantly nowadays as much as possible.

The Center of Excellence Treatable Traits has developed an asthma and pregnancy toolkit for healthcare professionals. Visit asthmapregancytoolkit.org.au

for more information and resources for your patients.

So what should a GP consider when they're putting together an asthma action plan for a patient and should that change during pregnancy.

Yes so I think once again it's really important to have an action plan. A lot of women have been asthmatic for a long time. They may have had one 5 or
10 years ago it's always good to once again review

their baseline function. Review whether it's still relevant to a woman once again renewing making sure that all the scripts and puffers are still within date and also once again not to assume that they know how to do it all these years. I'm just reviewing their technique of inhalers. I think a few sort of key points in pregnancy specifically is that sometimes woman may not have access to certain things or have the sort of underlying literacy to be able to comprehend very complex instructions so whether they're able to get to a hospital time in a timely manner whether they have the ability to understand the action plan provided in a certain language so I think all those things should be reviewed regularly. I guess in pregnancy because now we do have the fetal side of things to be worried about as well. Generally my advice is to have a very low threshold to escalate so if they're unwell with say a flu like illness or a cold and they've tried the action plan as recommended and things are still not improving to have a much lower threshold than normal to present to the nearest hospital or to GP just to make sure that both mum and bub is well.

Jolene, is it possible for asthma that hasn't been active since childhood or even has never been present before to present for the first time in pregnancy?

Yeah that's a really good question because in fact I have met a lady last week or two weeks before this who presented in the very same way so it is definitely possible for someone who has never had a history of asthma or has grown out of their childhood asthma to then represent during pregnancy with what looks like asthma and most likely it is going to be 

a recurrence of their asthma from before or a new diagnosis of asthma so as mentioned before all the physiological changes can make someone more prone to developing I guess airway hyper sensitivity and bronchial changes in pregnancy and in fact sometimes it's really good to you know really look into the diagnosis whether we've got the diagnosis right and you know obviously not to assume that it always is asthma. There could be a lot of other underlying causes or differentials in place so if someone presents with new asthma in in a pregnancy it's worthwhile definitely thinking of some 
diagnostic studies maybe lung function studies even some imaging to confirm the diagnosis but is definitely something that's possible.

And I can imagine if someone hasn't been dealing with asthma for most of their adult life to then have to deal with it there's all kinds of issues about knowing how they best look after themselves as well.

Correct so I think it's obviously a tricky time during pregnancy for a new diagnosis to be made and it can be quite terrifying for women to you know have that sensation where they couldn't breathe and suddenly gets really wheezy so I think lots of education, lots of reinforcement and lots of going through everything from basics up till you know what what's expected and what to expect going home as well as when the gestation progresses is really important. I think most importantly is once again regular reviews in clinics just to make sure that things hasn't really changed since the last time we've seen them and also just to make sure that there's still that connection there  even after the discharge from hospital.

Very cool. Jolene thank you so much for your advice. Before we go we'd like to introduce you to a little segment we call The Checkup. It's not too tricky we just want to know more about Jolene the person and the medical professional. So Maggie's going to ask you five surprise questions quick questions. Are you ready?
I am.

Okay Jolene. When you were little what did you want to be when you grew up?

I wanted to be an interior designer so I really like the art and I really like being in beautiful spaces.

I'm not super artsy but I like to say I like beautiful things.

What's the best outfit that you've ever worn to a costume party? That's a good one too. Probably a burlesque dancer. That's a long time ago that was in uni.
Sounds like a good party.

If you could impart a single piece of advice to a brand new medical student today what would you tell them?

I think the main thing is to always remember why you're doing this and to remember that the patients are the focus here and although the days are tough and the days are long it's about you know what the patients are going through and try to understand where they're coming from and what they're going through as well and try to be in their shoes and have a bit of empathy and compassion when we're talking to patients.

If you had Monday off and you didn't have to go into the office some Monday what would you do?

Probably go for a walk by the water either the beach or home river.

Probably just a nice coffee and then walk.

Do you have any secret or hidden talents? I wouldn't call that a talent but I can play a very big brass instrument. Want to give it give it a guess? Euphonium? It's bigger than that. A tuba. So I used to play the tuba in a marching band so I could play the tuba if needed at any point.
Oh my gosh you are so full of surprises. Thanks Jolene .

It's been great to have you. No problems thank you so much for our listeners at home or in the car or having a well-deserved break between patients. Thanks for tuning in. See you next time on sMater.