From the Mailbag...

Pregnancy vaccines, solid foods, Magic 8 Ball

If I’m being honest, “From the Mailbag” would just be a list of questions about seeing people with various vaccination statuses. And I will write about this again, since it’s clear people are still struggling. I’m working on other ways to talk about it, on how to make things clearer. Stay tuned. In the meantime, enjoy a couple of other questions I’ve gotten, including a request for a Magic 8-Ball…

COVID Vaccine in Pregnancy

Will you consider updating your piece on pregnancy and COVID vaccination (or writing a new one) as more data and research become available? The piece I read was from December, and I am curious about how much has changed in recent months based on new research and data.

In some ways, not much! In others, we do know a bit more. Let’s run it down.

First, trials in pregnant women are underway now. Which is good! You can see some details here about Pfizer. These will follow pregnant women for 7 to 10 months after vaccinating them between 24 and 36 weeks of pregnancy. This is helpful in a sense, but obviously the results are very long term.

(Before you flood with questions about kid vaccines: Pfizer will also be testing in kids 5 to 12 soon, and under 5 later this year. Johnson and Johnson has already said they will start testing in infants. Kids 12-15 are underway already. So we have a plan on kids, also, but similarly not immediate.)

Of course, these trials are not the only source of data, since many pregnant women are already being vaccinated, and followed in a registry. We have started to get just a little bit of information already about safety from this, although nothing published yet. The best thing I could find was evidence from a presentation at the Advisory Committee on Immunization Practice (ACIP). I’ve included a Twitter screenshot below (thank you @brennahughesmd) and the whole presentation is here.

The data here is based on about 275 completed pregnancies among about 2000 people currently enrolled in the registry. So, it’s a small sample still, but we’re starting to get some evidence. The table shows the comparison of adverse events for women who were vaccinated while pregnant (the right hand column) to the background risks (left hand column). The data are reassuring; adverse event rates are similar in the two groups. Clearly, we need more sample size, but early data is good.

I will note, finally, that at this point a lot of pregnant people have been vaccinated (way more than are in the registry). And we haven’t seen reporting on adverse effects, even anecdotally. This isn’t data, obviously, but it’s valuable in a sense as “absence of data.”

Timing of Solid Foods

Last week at my son’s 3 month pediatrician visit, his doctor said we can discuss starting solids at next months visit (if that’s something we want to do). Typically I see a lot of sources recommend that solids should not be started until 6 months, but I guess depending on your child’s physical ability (i.e., able to sit up on their own, grab, etc)., it can be as early as 4 months, according to new research. A lot of the sources that recommend starting at 6 months recommend that because of reasons you have already debunked, so I’m wondering if there’s some conflicting information. It looks like there’s some new data and research that points to 4 months being totally acceptable, but wanted to see if you were able to read through the lines on this. Anyway, thank you in advance if you’re able to blog about this because it seems others are looking for the same information (moms groups, Google searches).

One of my favorite parenting adages is: “Food is fun, until they’re one”. Which is to say that babies get most of their calories from breastmilk or formula in the first year, and food introduction is, at least in part, intended to introduce new textures, tastes, the idea of swallowing, etc. What I like about this is that it dials down some of the pressure around this — your kid isn’t eating entire chicken legs at 9 months? This is okay.

In terms of the date of introduction in the 4 to 6 month range. There are various studies which attempt to correlate date of food introduction with obesity later in life (here’s one example among many, here’s another). These are generally not randomized and as a result heavily subject to concerns that age of food introduction correlates with all kinds of other characteristics. The results are not especially consistent across studies, and combined with these causality concerns, the link seems very tenuous.

Babies vary in when they develop sufficient sitting and swallowing control to have food, so this is worth keeping in mind when you consider this. A 4 month old baby may mush around food more than eat it (the same is true for a 6 month old, perhaps less so).

One note on timing: we have increasing evidence that early introduction of allergens (around 4 months) lowers risk of developing allergies later. This includes peanuts most notably, but also milk and eggs. It may make sense to introduce these allergens at 4 months, although you don’t necessarily have to do it through solid food. Several companies (Ready, Set, Food; LilMixins) sell powdered versions which can be mixed with breastmilk or formula.

Magic 8 Ball

I think you should create a Magic 8 Ball search engine of your work. Readers could type in a question like “Should I have a second kid?” And the search engine could give an 8 Ball response “Outlook Good” or you could load in your own response “I don’t know you tell me” and then list links to your news posts or references to book chapters. It’d be funny. And useful.

I like this. There is already an app which you can get, made by a loyal reader. But it doesn’t give concrete advice. In the 8-ball world “Should I have an Epidural?” could yield “Ask again tomorrow”, with links to studies. I’ll look into it.

Also, should I have a second kid?

Let me check….“It is Decidedly So”

Weigh in!

Keep the thoughts coming. I don’t always write back, but I read everything.

Write to Me!

Where to Find Me

COVID School Dashboard

My Website

Family Firm


Expecting Better