Birth by C-section more than doubles odds of measles vaccine failure. Should I test?

[annjro]

@dugger Also I guess mums with health issues are more likely to have c sections & their genetics are affecting how baby grows up. Eg I have autoimmune diseases & I had a c section. My baby has my genes (please god let him favour his dad's health lol) so will be higher risk for auto immune issues.

 

[jdthcstl]

@kaferty I can't find a free version of the full study. But I suspect they are grouping premies or complicated pregnancies/births with less complicated c-sections. Or maybe, they are just flat out wrong, it is a big and unusual claim. I honestly wouldn't stress about it.

Also to put it in perspective, the average rate of failure is about 1 in 100, so if you are doubling your odds, it ~2 out 100 chance of having a breakthrough infection. Base rate really matters in science.

On antibody testing, this is usually a blood test your doctor orders. But as a researcher who worked tangentially on COVID antibody studies, antibody tests are a mess and it require a lot of specialized knowledge into understanding what test is appropriate and what type of immunity can be determine. Your doctor may not be equipped to help you interpret your results effectively and at the end of the day, you will get a really expensive piece of paper that tells you nothing. I saw a lot of doctors giving the wrong test to patients during the acute stages of the COVID pandemic, telling them they had a past infection, when in reality, all it was detecting was if they had the vaccine, or sometimes they would give the wrong test that wasn't sensitive to long term antibodies and failed to detect past infections. There were dozens of COVID antibody tests and they all had drastically different efficacy in detecting antibodies. Maybe Measles is different because it is a well known disease, but any time antibody tests come up, I get very skeptical.

 

[boutsour]

@jdthcstl For measles they should be able to draw titers to see if immunity is being built. In this situation it seems unnecessary because the child isn’t fully vaccinated yet anyways and doesn’t seem high risk. I found out when I went to nursing school that I don’t build immunity to measles no matter how many times they vaccinate me. I had to go to an immunologist to get cleared for clinical and they pretty much said some people just don’t build immunity to measles despite getting vaccinated. They said I likely never built an immunity when vaccinated as a baby and we just never knew because most people don’t have titers done unless if it’s for a job.

 

[annjro]

@boutsour Yes I got tested for MMR & chicken pox immunity when I started medical school. It's fairly straight forward. Apparently I was not immune to one of mmr (can't remember which) & had very low chicken pox titres. I had a booster!

 

[icantthinkofausername]

@kaferty I mean, it says that there’s an increased chance that a single jab does not provide immunity, but a second dose does… and we have a two dose schedule for exactly that reason: not everyone gets immunity from a single MMR dose, and a second dose increases the percentage of people who gain immunity from a vaccine.

At worst, I wouldn’t travel to places with measles outbreaks until they get their second dose. I’ve had three kids by elective c-section and haven’t had them tested for antibodies, I am not too fussed about it because the chances of them having immunity after the second dose is extremely high, and still really high after a single dose.

 

[green520]

@kaferty In the us, all kids are recommended to get two doses, one around a year and one around age 4.

 

[ellamwebb]

@kaferty Nah. I was born vaginally and MMR never took for me. I've had it about 6 times now and my titres still show no immunity. Thankfully, because the majority of the population have had the vaccine and it's worked as intended, I have never had measles, mumps or rubella. Yay for herd immunity.

 

[boutsour]

@ellamwebb Same!! I was born vaginally and no matter how many times they vaccinated me with MMR for nursing school I never built any immunity. I had to go to an immunologist to get cleared to go to clinical. I never had measles and I would’ve never known if I wasn’t in nursing school. I went to school in nyc and there are many local communities that are anti-vax, so while I’m covered by most peoples herd immunity, I did have to be careful in clinical rotations. Every few years we seem to get a few measles cases in the area and I’m always on edge. PSA: vaccinate your kids on schedule. Please don’t try to kill me. Thanks.

 

[kaferty]

@ellamwebb okay thanks. Heh, for a moment I thought you had measles 6 times!

 

[keithann]

@ellamwebb My people! Same here. I've been vaccinated so many times and I kind of argue with them now because really what's the point. I have a question, do you have any idea why yours may not have taken? I apologize if speculation isn't allowed here. I have an autoimmune disease and always wondered if that had something to do with it.

 

[icanonlyimagine18]

@kaferty I think there are a lot of things far more worth your time than trying to acquire a measles immunity test. If your kids are following the vaccine schedule, I would leave it at that. Remember that vaccination is more about herd immunity than it is about if individual's vaccines successfully conferred immunity.

 

[livinggrace]

@kaferty This is a fairly small study (1505) and if I’m reading it correctly it seems like many kids are covered once they get the second WHO recommended dose, which at least here in the US is around 4-5. For us testing titers wouldn’t be covered and I personally wouldn’t pay out of pocket for it before the second dose unless I was planning to travel to somewhere with higher levels in the community, there was an outbreak in my area, or I had other reason to be concerned.

 

[kaferty]

@livinggrace I know--- I'd just rather not wait as they are only 2.

 

[livinggrace]

@kaferty That's fair. Just giving my thoughts and I personally wouldn't do it. But I also have no plans to get my kids vaccines tested in general. I was a c section baby who had a failed MMR (found out during 1st pregnancy) and mines are both being c section babies. That may change if my area gets another outbreak but for now it's not where I would spend my energy or healthcare dollars.

 

[livinggrace]

@kaferty Thinking on it I think the main reason I wouldn’t is because even if you gave me the raw statistic of there’s about 12% chance that my kid’s MMR failed I wouldn’t have their titers tested just based on that (unless their doctor recommended) regardless of the reason for that statistic being slightly higher for them than some peers.

 

[dancequeen12]

@kaferty Full disclosure I did not read the study. So I am not commenting specifically on it. However, I did my PhD in infant gut microbiome field, and there are several researchers studying how the microbes in the infant gut affect vaccine response. This would be the hypothesis as to why being born by cesarean section might affect vaccine response, since we know that babies born by cesarean are colonized by different bacteria than those delivered vaginally. The immune system is trained in the gut over the first few months of life. This is far from the only study to find such an affect.

That said, I’m not sure that knowing whether your kids are actually immune or not changes much, and might just make you worry. If they aren’t, are you going to pull them out of school or never travel anywhere? It’s always possible a second dose would be more effective but it also might not be. Personally I’d just follow the vaccine schedule and then take normal precautions but not live like a hermit.

 

[dp1991]

@dancequeen12 What are your thoughts on the practice of "vaginal seeding" after C-sections, done in an attempt to expose the baby to the vaginal microbiome? In your educated opinion, is there something to it?

My son was born vaginally, but I am concerned about my baby's microbiome in the event that I have to get a C-section for a future kid, especially if they're a preemie (since they're normally given lots of antibiotics)

And is there anything you'd recommend doing during pregnancy to maximize the baby's gut health, besides just generally eating a healthy, varied diet? Are fermented foods during pregnancy a good idea? I know the microbiome is very important so I'm curious

 

[wiccankid]

@dancequeen12 That’s so interesting that babies born by cesarean are colonized by different bacteria than those born vaginally. What about babies born vaginally but en caul?

 

[dancequeen12]

@wiccankid That’s a good question. Plenty of vaginally born babies also “look like” they were born by c section. It’s rare to be born in the amniotic sac which makes it quite difficult to study, so we don’t really know. But having things like cervical exams during labor (the more the worse), amniotomy, instrumental delivery, antibiotics during labor, being born in a hospital, people other than mom/dad heavily handling baby in the first days, giving baby a bath too soon and more all highly likely negatively affect this transfer of maternal bacteria, despite vaginal delivery

That said, breastfeeding also exposes baby to maternal microbes (they seem to be transplanted to the breast from the gut, likely from immune cells but we aren’t totally sure how) and can help

 

[kaferty]

@dancequeen12 well, I would just push for an earlier 2nd mmr vaccine.