Rachel Pasquesi, MD: Hi, my name is Rachel Pasquesi and I'm a physician that specializes in obstetrics and gynecology with St. Louis Children's Hospital and I'm a Mom Doc.

Melanie Cole, MS (Host): When a baby is born prematurely, their lungs may not be fully developed, which can lead to respiratory issues. Today, we're going to learn how the role of antenatal corticosteroids that can save a baby's life, really work.

Welcome to MomDocs, the podcast from St. Louis Children's Hospital. I'm Melanie Cole. Dr. Pasquesi, thank you so much for joining us today. What are some of the more serious health concerns for premature infants when you're working with the families with these babies? Tell us what is of greatest concern.

Rachel Pasquesi, MD: So there are lots of concerns when a baby is born prematurely, ranging from their respiratory status to their gut health to how their blood vessels work in their brain, all of those different types of things. So we try to optimize everything we can for the patient and their baby prior to delivery if we're at all anticipating that a baby might come early.

Host: When we're thinking of triage and the things that are most important, obviously respiratory issues are so important. Tell us a little bit about what I mentioned in the intro. What is an antenatal corticosteroid? Why are they administered during pregnancy? How do you know if the baby's going to be preemie? So tell us a little bit about them.

Rachel Pasquesi, MD: So steroids are medications that help to accelerate fetal organ maturation specifically within the lungs. And you're right, respiratory status is so important for babies, that by optimizing that, this medication can then lead to a decrease in morbidity and mortality for babies who are born prematurely.

Things that might cause somebody to be born prematurely is if a mom is in preterm labor or if she breaks her water early. Those things put a mom at really high risk. And so those might be somebody that are candidates for getting preterm steroids.

Host: So this is something you administer once you know that she is going into labor. Yeah?

Rachel Pasquesi, MD: Yes. So if we have a suspicion that somebody's going to deliver within the next seven days, that's the person we'd want to administer them to. There are specific gestational ages that we recommend them. So they're usually administered to moms who are preterm or late preterm.

Host: Well, then how do they benefit preterm infants? If you give it to the mother during pregnancy, close to labor time, how do they work? What are they doing?

Rachel Pasquesi, MD: So again, they specifically accelerate fetal lungs and that way they are able to decrease respiratory distress syndrome, intracranial hemorrhages, necrotizing enterocolitis, and also death after a baby is born.

Host: Wow. Isn't that amazing? I just think corticosteroids are really, what a find for the last, what, 50 years, right? These are something novels have been written about. They're quite amazing. Now, tell us a little bit about how many doses you administer. Is this something ongoing? Is it a one time shot? What goes on?

Rachel Pasquesi, MD: So when we consider giving steroids again, we're gonna want to give it to somebody who's at risk for delivering within the next seven days. A single course is recommended for anybody between 24 and 34 weeks, and then you can always repeat that dose for patients if they're before 34 weeks if they had an ongoing risk for delivery.

We would never do more than two doses though before 34 weeks. Steroids can also be considered after 34 weeks between 34 and 36 weeks and six days if a patient has not already received steroids. So in that late preterm time frame, they would only get one dose of steroids. There is a little bit of difference between how many actual shots somebody is getting depending on which steroid type they get.

There's betamethasone and dexamethasone, and there's no difference between those types of steroids. Both are very beneficial. If somebody happened to get betamethasone, they would get two shots, 24 hours apart. And if somebody was getting dexamethasone, they would get four shots in total, 12 hours apart.

So both of these are overall lasting a period of time about 48 hours in which somebody is getting the medication.

Host: Are there any side effects for the mother?

Rachel Pasquesi, MD: Not significantly. There are risks to the mother. The steroids can increase a mom's sugars, especially if a mom already has diabetes or developed diabetes in pregnancy, but the benefits of the steroids for the babies typically outweigh the risks of increasing the mom's sugars.

Host: That's an important point, Dr. Pasquesi. Thank you for mentioning that. And what about the pregnancy experience, the delivery process. Do the steroids have any effect on that?

Rachel Pasquesi, MD: No it doesn't. Steroids have a good benefit as soon as they're being administered. And so therefore, even if a mom is going to deliver quickly and might not even receive those full doses of steroids, then we go ahead and give them to them.

It's also a reason we don't delay proceeding with a delivery if a mom is getting steroids. So we don't usually wait for the full administration of steroids if delivery is otherwise indicated. The best benefit for steroids, though, is within the first two to seven days after administration, though. So if there is a reason that we can safely delay delivery until that time frame, then we would consider doing that as well.

Host: What about multiple pregnancies, twins, triplets? Are there special considerations? Can those be used as well?

Rachel Pasquesi, MD: They have the same indications as a singleton pregnancy. There's no additional concerns for the babies or for the mom if a mom has multiples or not. So they can be safely used in a multiple pregnancy.

Host: Dr. Pasquesi, can you discuss your personal story with antenatal corticosteroids?

Rachel Pasquesi, MD: Yeah, absolutely. So my water broke right at the end of 34 weeks, and so when I came into the hospital, I knew that my baby was preterm, and so knowing that there are very little risk to steroids, but such good benefit, I decided to go ahead and get a steroid shot. My baby actually ended up delivering before I could even get my second steroid shot, but since steroids have such a significant benefit, even after one dose, I thought it was really important for them to get it.

My baby ended up still needing to go to the NICU and transition and needing breathing support, but it's hard to imagine how much more they would have needed if I wouldn't have gotten that steroid shot.

Host: This is so interesting and something that I imagine not that many people know really what goes on in this situation. So as we wrap up, what should expectant mothers and their families know about these antenatal corticosteroids? How they discuss their use with healthcare providers such as yourself, are these questions, what would you like them to know?

Rachel Pasquesi, MD: So steroids are one of the most important therapies available to improve newborn outcomes. So if a mom is concerned that she's in preterm labor or that her water broke early, one of the best things that they can do is present to the hospital so that steroids as well as any additional indicated therapies can be started right away.

Host: Thank you so much, Dr. Pasquesi, for joining us today. And for more advice and articles, please check out the MomDocs website at childrensmd.org. That concludes another episode of MomDocs with St. Louis Children's Hospital. Please remember to subscribe, rate, and review MomDocs on Apple Podcasts, iHeart, Spotify, and Pandora. I'm Melanie Cole. Thanks so much for tuning in today.