What you Really Need to Know about Pregnancy

Alcohol while breastfeeding

• Emily O. I am glad you asked since people seem to have a lot of thoughts about this. It will be in book #2 but ... In moderation, it is fine. The concentration of alcohol in breast milk is very low even if you drink a ton. There is an ice paper where they measure the concentration after 4 shots of tequila (DO NOT DO THIS IF YOU ARE PARENTING). It is still extremely low, too low to be a problem. By extension, if your question is whether you can have a glass of wine (or, say, one tequila shot) the answer is yes. The alcohol concentration in breast-milk would be similar to that in orange juice. If you do want to totally avoid exposing your baby to this AT ALL you can wait two hours after a drink for the alcohol to clear. 4 hours for two drinks. there is no need to pump and dump.

Thank you, Emily Oster!

Coffee

• Emily O. Ah, coffee. It's the best. The big worry with coffee - or, really, any kind of caffeine - is the possible link with miscarriage. When researchers look at pregnant women, they see that women who drink a lot of coffee - we're talking five, six, seven cups a day - are more likely to miscarry early on than others. This is the evidence that leads to some caution with coffee. But there are caveats. First, when we look at more moderate consumption - two or three cups a day, say - there is no evidence of increased risk. And even the official guidelines, which are typically VERY conservative, say up to two cups a day is fine. Second, even at very high levels of consumption the conclusions are not iron clad. Women who drink a lot of coffee are different in other ways than those who drink less (for example, they are more likely to smoke) and it's hard to know if it is really the coffee. By having two cups a day you're staying on the safe side, but it might be unnecessary I do not, however, have any great answers for your mother in law. Maybe just tell her it's decaf?

Quantity of fish

• Emily O. Hm...I cannot see why. Fish is good. This sounds made up. Oh, here we go: here is a nice summary from Slate discussing how the FDA guideliens now say 8 to 12 ounces per week, like as a minimum, rather than saying do not have more http://www.slate.com/articles/health_and_science/medical_examiner/2017/05/pregnant_women_should_eat_more_fish_not_less.html And these guidelines do not specify type. They are likely to be conservative since mostly people eat tunafish, which has the mercury issue. In conclusion: please ignore this.

• Sara Thank you! It's funny, after reading the Slate article you linked, I see now that I was definitely interpreting the 12oz as a limit instead of as a goal. Our brains become so limit-focused during pregnancy that it's hard not to see it that way. Thanks again!

• Emily O. You're welcome! I totally agree. It's hard to step out of the "what are they telling me not to do now" mindset!

No question from me but I just wanted to say that I loved your book! And not only because I was able to drink coffee this time around...!

• Emily O. Thanks!! I am very happy to hear this...

New book, twins, and music in the womb

• Emily O. Congratulations! April 2019 is tentative release date so... will be in time for at least soem of your first year (and the new book covers through ~age 3 so will hopefully be helpful). There is much stuff on twins, largely around methods of delivery. I'd say the best place to look is to start with Cochrane Review (http://www.cochranelibrary.com/cochrane-database-of-systematic-reviews/index.html). This database is searchable and the reviews try to synthesize the existing evidence. And they usually have a lay summary. Womb music: no evidence. People say their baby likes the same music in and out of the womb - could be true or not. I mean, if you want to read to your belly that is great! I definitely talked to my kids about economics at lot while they were in there. So far they haven't written any papers, though.

• Edward Thank you! April will give us ~ 6 months under our belts so it will be a welcome resource.

Cough Drops

• Emily O. Thanks! Not that there is any evidence for, no. Standard things like Halls, Riccola, etc, are all considered fine.

Caffeine and kicking

• Emily O. This is interesting! It might be that the baby is responding to the caffeine (or the sugar?) but there is no reason to think it would be a problem. Babies often move more when you eat something, or are sitting down. So, in short, no you shouldn't worry. The baby is getting some caffeine, since it crosses the placenta, but (see evidence) there is no reason to think it's a problem. One note: some people find that if they are breastfeeding and they have coffee their kids get irritable. If you actually think your baby is responsive to caffeine, it could carry over. For your sake, I hope not.

Parental leave

• Emily O. I'll talk about this some in the new book but, yes, there is some evidence that maternity leave in the first few months of life is good for babies. Here is a somewhat dense paper on this (https://web.stanford.edu/~mrossin/RossinSlater_maternity_family_leave.pdf, by an economist, which summarizes the literature. Maybe you can give it to your employer and see if they want to wade through it. The bottom line is that something like 3 to 4 months has been show to be good for babies in short and long term, although longer than that doesn't seem to matter.

• Edward Excellent, thank you.

Marijuana safe during pregnancy?

• Emily O. This is a good question! i think the answer is we do not yet really have enough data to know. The NY Times actually did a little thing on the risks of marijuana a couple of days ago (https://www.nytimes.com/2018/05/07/upshot/its-time-for-a-new-discussion-of-marijuanas-risks.html) and included some discussion of pregnancy. The bottom line is we do not have much evidence in either direction for safety or not, and it's hard to know given that smoking pot is often associated with other behaviors. I am guessing we'll know much more about this in a few years now that this is legal...

• Corey Yah, that makes sense. Thanks

Sushi during pregnancy

• Emily O. There are basically two worries. First, that sushi can carry food-bourne illness like salmonella. This is true, although the risks are no greater than if you were not pregnant. What I say in the book is that you should make sure your sushi is from a high quality vendor - like, no gas station sushi - but this is true whether or not you are pregnant. A second issue is that some sushi fish can contain a lot of mercury. Specifically, tuna and swordfish (or at least these are the most common high mercury fish). Mercury is not good during pregnancy (bad for baby's brain) so you should avoid these particular fish. But if you are craving a salmon roll, go for it.

• Susan Thank you, Emily! I'm excited to learn about and read your book!

Bed rest

• Emily O. Not really, no. There are a few activities you do not want to do - skiing, tackle football, basically anything where trauma is possible. And your ligaments get looser during pregnancy so it can be easier to get injured exercising. However: if it feels okay, and you are having a normal pregnancy there is no medical reason not so. One caveat is that there are some placental issues (previa, specifically) where sex is not recommended. These are usually detected around 20 weeks. So, that is a limitation. Hopefully you are not in that boat.

• Edward Thanks again.

Drinking alcohol during 2 week wait

• Emily O. Yes, this is hard to find good information about. My sense of the literature is that binge consumption is bad, since it can lead to (effectively) embryonic destruction. But a glass of wine with dinner - we just have nothing in the data to suggest that is a problem for conception.

• Emily O. Probably the best evidence on this is from a Danish study (editorial discussion it here https://www.bmj.com/content/354/bmj.i4540) which shows that there is MAYBE some evidence that 14 or more drinks a week lowers fertility, but below that there is no effect.

• Charlotte Phew—14 drinks is definitely more than I was planning on. Thanks for the response!

• Emily O. Yes, I should have put in that 14 drinks a week is above what they'd recommend to anyone - pregnant or not. So, don't do that anyway!