Preterm Labor: Magnesium Sulfate vs. Nifedipine

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Hello!

I am presently at a hospital where I was admitted for PROM at 31 weeks. Was about 2cm dilated and put on magnesium sulfate. I am wondering what others think of using Nifedipine as a substitute for mag sulfate? For the past three days, I've experienced only 2 contractions on the mag sulfate and the dose has been lowered to about 1.5 grams.

The reason I ask, is because in a pregnancy where I delivered at 27 weeks (also due to PROM - complete rupture), I was put on mag sulfate as a first line of treatment for two days in order to receive betamethasone shots, and then put on Nifedipine. I was able to carry about 3 weeks on the Nifedipine before delivering in this situation. The reason my OB chose Nifedipine at the time was because it seemed to carry fewer side effect for both myself and baby.

Being in a different hospital with this baby, I do not even have a rapport with the OB who was assigned to me. He is an older OB and pretty set in his ways, and I can understand he probably has had many babies delivered fine on mag sulfate. In this hospital, I was told that their usual course of treatment is magnesium sulfate until I deliver, which is hopefully three weeks later. Since this child shows enlarged kidneys (having fluid) on ultrasound, that has increased my worry as to what medication is best for fending off preterm labor. At this point, I would like the least amount of risk for both baby and myself.

Can Nifedipine and Magnesium Sulfate both be as effective in preventing pre-term labor?

Which has the least amount of risk?

Any opinions are welcome...

Oh, also... my baby that was born at 27 weeks did quite well in the NICU. She was able to breathe on her own initially; no brain bleeds. She really seemed to beat the odds. She is a walking and talking 3.5 year old today. With her treatment being so successful, I guess that I why I am hesitant to remain on the mag sulfate and would prefer to switch to Nifedipine at this point.

I went into preterm with triplets at 22 weeks. They were able to stop my labor with Mag, and the decided to try a switch to Nifedipine. Because the contractions had stopped with the Mag, the Nifedipine kept them from restarting for a couple more weeks. Then they tried Terbutaline. Finally after the Terbutaline stopped working, they switched me back to Mag.

From what I understand (and it's been 4 1/2 years since this happened), I think they consider Mag to be the big guns and the Nifedipine to just be the pea-shooter. I think they just use what they need to until things require a stronger or weaker med. We were able to hold off delivery until 27 weeks 6 days.

Good luck! I'll be thinking good thoughts for you two!

First of all Magnesium and nifedapine are contraindicated together. I work in a tertiary care center and high risk pregnant moms is my specialty. It depends ont he doctor, I have seen Proms remain on magnesium until deliver, I've seen them switch to nifedapine or terbutaline motrin until 32 weeks. Although one of the new trends comming out is magnesium until in the steroid window then taken off all tocolytics. (reason being infection) people who are SPPROM deliver for 1 of 2 resons usually, infection or they deliver anyway. The perinatal doctors and neonatal doctors I have spoken to prefer a health premature baby than one sick more mature baby. Magnesium can mask infection and keep a baby in longer when the body is trying to get rid of it due to infection. I don't say these things to scare anyone but ask your doctor to switch you to something if you want or express fears of infection. Good luck I am seen many women go a couple of weeks to a month OK. Also as far as your 27 weeker. That is my pet peeve as a nurse just because your 27 weeker did fine that doesn't mean a 31 weeker will do OK sure it has a better chance but each child is very very diffrent. Some 24 weekers do fine (few and far between) I've also known some 32 weekers to do not so good.

Specializes in Maternal - Child Health.

I had very resistant pre-term labor with both of my pregnancies, and MgSO4 was the only drug that was truly effective in keeping my contractions under control. I was able to go for short periods of time on a combination of nifedipine and terbutaline to get a break from the mag, but I always ended up breaking thru and having to go back on the mag. Eventually, the nifedipine had to be DC'd altogether, as it caused my B/P to bottom out. Thankfully, I was about 35 weeks, so it wasn't a huge issue. I also tried Indocin, but it caused such a drop in my amniotic fluid that it was also DC'd.

MgSO4 is a very unpleasant medication with a multitude of side-effects (which I'm sure you already know), but the docs and nurses worked very hard with hubby and me to come up with a plan of care that was tolerable, including short breaks home with sub-q and po meds and home monitoring.

Perhaps you could negotiate with your doc to allow a trial of nifedipine while you remain hospitalized. If the results are satisfactory, then perhaps home with home monitoring.

Best of luck to you. I know how stressful this is, and wish you much success in bringing a healthy term baby into the world!

Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

I was on nifedipine w/my daughter (started preterm labor at 30 weeks and had had a prior baby at 34 weeks gestation). It was very successful at keeping me pregnant til my 38 week planned csection (baby was breech). I was unable to use terb due to a strange idiopathic increase in my heart rate to 105-110 during my pregnancy.

The above poster is right; nifedipine (Procardia) IS NOT to be used concommitantly with Magnesium! Mag is used for those whom terbutaline or nifedipine fails, only. As all here know, every day the baby stays inside, is so much the better. Anyone with a history of PTL should be considered at risk during each subsequent pregnancy as well. Sadly, the PTL rates are RISING, not falling, and most treatments are marginal, at best. Whether to treat or not, is controversial, in the absence of cervical change. Cervical change is your big factor in whether or not to treat pre term contractions in women.

HTH.

I feel I need to remind people that she is ruptured not just in preterm labor, delivery is not the only thing that she is trying to avoid. She is trying to avoid infection. Also fluid helps the babies lung mature granted the baby is constantly making fluid but if the lungs aren't getting any fluid no matter how long the baby stays inside the lungs will not develop

I feel I need to remind people that she is ruptured not just in preterm labor, delivery is not the only thing that she is trying to avoid. She is trying to avoid infection. Also fluid helps the babies lung mature granted the baby is constantly making fluid but if the lungs aren't getting any fluid no matter how long the baby stays inside the lungs will not develop

Is Nifedipine dehydrating or the magnesium sulfate? I know I've read some others are, so just curious. Even with a full rupture with my first (the 27 weeker) I had the Nifedipine. Once when contractions acted up on the Nifedipine, a fluid IV to hydrate the uterus helped subside contractions.

I just want to be able to make an informed choice and know the risks of each, along with what is best for gestational age at this point. It was very hard to hear one OB say magnesium sulfate is the only way to go after my first experience with PTL and the OB wanting to try and avoid mag sulfate because of the fetal/maternal risks he felt. Perhaps consulting with the neonatalogist might be a good idea to see what they like to see at this point? I've met once with the neonatalogist and know he would like to see me reach 34 weeks if possible.

The OB actually wanted to deliver me at 31 weeks when I presented with PROM since I had the betamethasone shots at 26 weeks. (I had been home on bedrest since and not on any meds -- just a positive fetalfibronectin result @ 26 weeks and uterine irritability.) So far, my labs have come out okay. No infection or GBS. Should I ask about assessing fetal lung development? Is it possible to do with ruptured membranes without an amnio? I'd hate to take water away with an amnio. I wasn't comfortable delivering right away at 31 weeks without knowing if I had infection or not or knowing how the lungs are at this point. I remember all too well how long my 27-weeker was in the NICU. But, I also realize it's important to assess each day and go with the flow.

I did bring up Nifedipine to the on-call OB over the weekend to see what they think of it here and he basically said, "We are better at dealing with magnesium sulfate." Not quite sure what to make of that, other than he probably didn't want to go switching orders over the weekend on the other OB. ;-)

Jennifer

Thanks to all for your feedback!!

Specializes in Maternal - Child Health.

Wishing you all the best!

I understand how frustrating it is to hear different opinions and options from different docs. It probably sounds a little "lame" to hear the weekend OB say that "We are better at dealing with MgSO4 here," but it is probably true. Docs in different areas often learn different "customs" in treating their patients. Having moved around a lot, and worked in hospitals all over the East coast and midwest, I can attest that there is often a huge difference in how docs treat their patients based on where they trained and where they are currently practicing.

With my first baby, I tried the terbutaline pump, but my doc was not very skilled in adjusting the dosage as the need arose. I don't think he was at all comfortable doing so, so the pump quickly failed, and I had to resume po meds (every 2 hours, with much greater side-effects due to the higher dosage). Clearly, my treatment was dictated by his experience and comfort level with the med.

With my second baby, I found a doc with personal experience using the terb. pump. (His wife had pre-term labor with all 3 of her pregnancies.) He could have written a book on that method of treatment. He was far more skilled, and laughed when I suggested that the pump may not work for me, based on past experience. He was far less incllined to use MgSO4, although it did become necessary on a number of occasions.

I guess the point of this long-winded post is to suggest that you consider getting more than one opinion from docs with different treatment perspectives. I was fortunate to find providers that were willing to work with me to devise a treatment plan that we could all live with. I was also blessed with 2 beautiful, healthy girls, and pray the same for you.

Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.
I feel I need to remind people that she is ruptured not just in preterm labor, delivery is not the only thing that she is trying to avoid. She is trying to avoid infection. Also fluid helps the babies lung mature granted the baby is constantly making fluid but if the lungs aren't getting any fluid no matter how long the baby stays inside the lungs will not develop
I get that. Anecdotally, I was ruptured ONE WEEK (and remained on bedrest in the hospital) before they delivered my son and that made all the difference in the world. He spent only 7 days in the NICU (versus likely much longer if they had rushed to deliver me) ----as the L:S ratio did indeed rise in his lungs in just that week I spent on bedrest and pregnant.

The fluid was copious enough, even when I delivered him, there was plenty for him to "float around in" and plenty to test for L:S ratio in that week's time. I do think they know what they are doing here--- and it is prudent, as long as she remains free of infection (they did q12 CBC on me to ensure that). On the day I finally spiked a bit of a temp, I went into spontaneous labor and 18 hours later, delivered my 34- week 5 lb 15 oz boy. His apgars were remarkably good and he spent only one day on supplemental oxygen, the rest of the time was to rule out any form of infection. 33 versus 34 weeks made a HUGE difference in my son's life anyhow.

Thank you for the reminder, but I did see what she was saying from the start. I guess I did not explain myself very well. Rofl I am good at that...... :coollook: :rotfl:

Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.
Wishing you all the best!

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I guess the point of this long-winded post is to suggest that you consider getting more than one opinion from docs with different treatment perspectives. I was fortunate to find providers that were willing to work with me to devise a treatment plan that we could all live with. I was also blessed with 2 beautiful, healthy girls, and pray the same for you.

I agree.

I'm curios are you still leaking fluid???????

Yes you can get fluid to send for fetal lung maturity without an amnio one of two ways lay down for a couple hours and not get up then sit on a bedpan and see what trickles out (amniotic fluid) You can also go in with a speculum and collect the fluid with a syringe.

I guess the point of this long-winded post is to suggest that you consider getting more than one opinion from docs with different treatment perspectives. I was fortunate to find providers that were willing to work with me to devise a treatment plan that we could all live with.

Thank you for your advice. I would like to get a second opinion, but at this point I don't know how to go about doing it. At this point, since I don't have a rapport established with this OB (I was supposed to deliver at a different hospital), I'd prefer to switch physicians. We clearly have a personality clash -- I need someone who can communicate for I don't buy completely into his vision, and he pretty much dismissed my ideas of Nifedipine to replace the mag sulfate. He didn't say anything bad about Nifedipine, just that "this is what we do and the mag sulfate is better." Should I pursue a second opinion or switching OBs through patient services or attempt to contact different OBs on my own?

Baby is pretty non-reactive right now, although I know that due to the side effects of mag sulfate that is probably normal... She was capable of having reactive non-stress tests when i first arrived, though, so naturally I'd prefer to watch things a little closer.

How often do most OBs order fetal monitoring when on mag sulfate? This OB has not even ordered the non-stress tests; the on-call over the weekend did, and this OB didn't have intentions of ordering any... The fetal heartrate is checked it seems once a day by a nurse.

I'm kind of wondering if I was "spoiled" for having gotten a two non-stress tests every day with my 27-weeker while on Nifedipine? While on mag sulfate with the 27-weeker, I was constantly monitored and on complete bedrest.

To date, there is also no ultrasound or biophysical profile scheduled, and this is something my regular OB was to follow up with, so I mentioned this when I spoke with this OB...

I've had a fetal demise at 36 weeks, m/c @ 10 wks, and m/c @ 8 wks in addition to the PTL history, so I wonder if my emotions are doing the thinking and if what is being done is "standard," or if I should have valid reason to be concerned?

Thanks!

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