Young maternal age is one risk factor and could be associated with cocaine use, but is that actually contributing to the increasing trend over the past 10 years? Are there any other hypotheses out there?

yes I think in addition to the bove; use of Marijwana may contribute in increasing the trend of Gastroshisis.

agree that use, accessibility, and the normalization of marijuana use as not harmful has increased; in Canada at least. However, in the epidemiological studies I've read, specific control for cigarettes, marijuana, and other drug use has been difficult to accomplish to the degree that they are highly correlated and likely under-reported. Furthermore, the stigmatization of one drug more than another may bias the self-reporting.

A mouse-model study found that a low protein and zinc diet combined with carbon monoxide (CO) exposure resulted in gastroschisis. This was somewhat confirmed in a human case-control study.

It seems to me that the exposure to combustion by-products, such as CO is the risk factor when combined with malnutrition, rather than the active ingredient of marijuana (THC) or nicotine in cigarettes. This leads me to believe that exposure to high levels of air pollution (mainly indoor air pollution via old wood stoves/fireplaces) could be a population-level risk factor able to be mitigated.

Yes, young and first time mother is known to be the risk factor. Drug use? Do not know. I used to practice in deep South with two level 3 NICU about 80+ daily census and had roughly 8-10 gastroschisis a year. Now, I work in mid-West with one level 3 NICU and can have 4 gastroschisis in one week and maybe 12-16 cases a year. Drug use is not as popular in my new place but environmental factor maybe the culprit. Here we also have unbelievably high incidence of complicated congenital heart defects, omphalocele, and other rare anomalies.

Interesting. Thanks for the input Ru-Jeng. I've seen consistency of studies reporting a minor role of vasoactive risk factors in the etiology of gastroschisis, but not support for a vascular disruption hypothesis. NSAIDs seem to be a consistent risk factor. In one study as part of the National Birth Defects Prevention Study, an interesting interaction with maternal age >25 years old showed greatest risk for both smoking and NSAIDs (Werler MM. Am J Med Genet A. 2009 Jul;149A(7):1399-406).

I am skeptical about the hypothesis of NSAID. They are commonly used drugs and you may taking them without even realizing it. Recall bias is always a big concern in this kind of research unless you really checking the meconium of the babies. Also, the epidemiology study result only tells us an association but not cause-and-effect relationship. This may also be the issue between illict drug use and gastroschisis. It may just be a secondary association like "young teenage, first time, moms have higher chance to use illicit drugs. They conceived just because they were high after drug use and do not even recall who is the real dad or what actually happened". The NSAID may just because the age is associated with more headache or migraine to those women.

I do not know the answer to the question on aetiology, I wish I dd. Here in Queensland like so many places in the world we have seen a steady rise since the 1970s. The current incidence here is 1/2000 live births. Gastroschisis has however been around for a long time, the first report coming from Glasgow in 1733.