Women had a lot to say about what works — and what doesn't — for treating morning sickness, after we ran a post summarizing the evidence for home remedies and over-the-counter meds.

NPR's Facebook feed lit up with comments from women saying that ginger, acupressure and other home remedies, which were recommended for mild symptoms in a medical journal article published Tuesday, did nothing to tame their nausea and vomiting.

As one woman wrote in response to our post:

If you have severe morning sickness, like I do currently, these things do literally nothing. Don't perpetuate the common conception that morning sickness is a mild woman's ailment that needs ginger tea and an 'it'll pass.' For some it is; for many, it isn't.

Severe morning sickness, called hyperemesis gravidarum, can be debilitating, even life-threatening; it affects about 3 percent of women, according to the American College of Obstetricians and Gynecologists.

We checked in with Dr. Aaron Caughey, chair of the department of obstetrics and gynecology at Oregon Health Science University and an author of ACOG's guidelines on treatment of morning sickness, to ask why it's so hard find effective relief for morning sickness. He replied by email while traveling. (Thank you, airline Wi-Fi!).

One great thing about the conversation in NPR's Facebook feed is that women are sharing a lot of advice on what's worked for them, from specific medications to crackers. Are they on target?

This comment about never having an empty tummy being helpful is something I commonly recommend. It seems like hypoglycemia leads to nausea and then they can't keep anything down and get more hypoglycemic. So I recommend crackers (saltines, goldfish, graham) to be kept in one's purse, next to the bed, etc .... and to eat at least one or two every hour .... at night, when getting up to go to the bathroom, a cracker as well.

I'm wondering if OB-GYNs perhaps give morning sickness less attention because they believe that most women don't have serious problems with it.

I don't know that OB-GYNs are dismissive of these symptoms, as we hear them from many women. It may be that we know that not one approach works for all women, so we have to just cycle through a range of over-the-counter and then prescription approaches.

Then there's the issue of the poor quality of medical research on morning sickness. The JAMA reviewers found that just 35 studies out of 13,000 were strong enough to be included, and those 35 weren't all that great. I'd imagine you had similar experiences with your ACOG review. Why isn't there more good research on morning sickness, considering that most women experience it while pregnant?

There is not enough research on pregnancy, period. During the first trimester of pregnancy, when pregnancy nausea is often the worst, is also the time for embryogenesis. Thus if you want to study a medication that could treat nausea in pregnancy, you would need to do many animal studies first to show that the effect on embryogenesis was nonexistent.

Even by doing so, there still could be an effect on the developing human embryo. Thus this is one of the most challenging conditions to get the pharmaceutical industry to study. Of note, the nausea of pregnancy may have been protective as a species because it kept women from trying to eat potentially embryo-toxic or teratogenic substances.

Women understandably get frustrated when recommended treatments like ginger aren't helping with the nausea and vomiting. When should someone consider moving on to prescription medication to treat morning sickness?

The medications that are commonly used have been used for many years, so are incredibly unlikely to have a negative impact on the developing embryo. In terms of when, this is something to discuss with your obstetric provider. Certainly if hospitalization for fluid has been required, it is time to try medications, but for many women it should be before hospitalization is necessary in order to prevent that from happening.

As a follow-up to that: The ACOG guidelines backed off on recommending the medication Zofran because of concerns that it may be linked birth defects. Do we have enough data to really know what's safe?

The word safe is challenging. I think most of us generally think it is safe to drive in a car, but of course as we all know, it is actually more dangerous than flying. Flying is pretty safe, but of course, there is not a zero risk. So, what risk is one willing to take? With regards to the Zofran issue, recent evidence demonstrated an association with some birth defects as you noted, so while the evidence isn't conclusive, we are trying not to use it except in more extreme cases.

Ultimately, women want to get through the pregnancy and deliver a healthy baby. As awful as severe morning sickness can be, does it pose a risk to the baby?

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