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An Israeli agricultural engineer inspects marijuana plants at the BOL (Breath Of Life) Pharma greenhouse in the country's second-largest medical cannabis plantation, near Kfar Pines in northern Israel, on March 9, 2016.
The recreational use of cannabis is illegal in the Jewish state, but for the past 10 years its therapeutic use has not only been permitted but also encouraged. Last year, doctors prescribed the herb to about 25,000 patients suffering from cancer, epilepsy, post-traumatic stress and degenerative diseases. The purpose is not to cure them but to alleviate their symptoms. Forbidden to export its cannabis plants, Israel is concentrating instead on marketing its agronomic, medical and technological expertise in the hope of becoming a world hub in the field.
 / AFP / JACK GUEZ        (Photo credit should read JACK GUEZ/AFP/Getty Images)
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An Israeli agricultural engineer inspects marijuana plants at the BOL (Breath Of Life) Pharma greenhouse in the country's second-largest medical cannabis plantation, near Kfar Pines in northern Israel, on March 9, 2016. The recreational use of cannabis is illegal in the Jewish state, but for the past 10 years its therapeutic use has not only been permitted but also encouraged. Last year, doctors prescribed the herb to about 25,000 patients suffering from cancer, epilepsy, post-traumatic stress and degenerative diseases. The purpose is not to cure them but to alleviate their symptoms. Forbidden to export its cannabis plants, Israel is concentrating instead on marketing its agronomic, medical and technological expertise in the hope of becoming a world hub in the field. / AFP / JACK GUEZ (Photo credit should read JACK GUEZ/AFP/Getty Images)
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Story highlights

Seven in 10 cannabis dispensaries in Colorado recommended products to women posing as pregnant customers

Health effects of cannabis on a fetus could include low birth weight and developmental problems, experts say

(CNN) —  

A majority of cannabis dispensaries in Colorado recommended their products to women posing as pregnant customers with morning sickness, clashing with doctors’ warnings about the potential harms, according to a study published Wednesday in the journal Obstetrics & Gynecology.

Of 400 randomly selected dispensaries in Colorado, about seven in 10 recommended cannabis products as a treatment for morning sickness. Nearly two-thirds of the employees who answered these calls based these recommendations on “personal opinion,” and more than a third said cannabis was safe during pregnancy. Roughly 32% of employees recommended the caller talk to a health care provider without the caller having to bring it up herself.

“I was really surprised,” said study author Dr. Torri Metz, a high-risk obstetrician at Denver Health in Colorado, where marijuana was legalized in 2012. “I did not expect dispensaries to be recommending cannabis products to pregnant women.”

Metz said women seek information on cannabis use during pregnancy from a variety of sources beyond their doctors – including the internet, friends and family.

“Women are hesitant to disclose any kind of drug use in pregnancy to their health care providers for fear of potential legal ramifications or involvement by social services,” she said.

Experts worry that some of these women may seek advice from cannabis retailers, expecting that they have specialized knowledge on the drug’s safety during pregnancy.

In the study, medical dispensaries were more likely to recommend cannabis products than retail dispensaries: About 83% and 60% did so, respectively. The authors note that the employees they spoke to may not reflect the official policy of a given dispensary.

Dr. Katrina Mark, an OB-GYN who was not involved in the research, wrote in an email that the term “medical dispensary” is a “misnomer.”

“They are only licensed to dispense to people who have medical marijuana cards,” said Mark, an assistant professor in the University of Maryland School of Medicine’s Department of Obstetrics, Gynecology and Reproductive Sciences. “This does not mean that they are staffed by people that have any sort of medical education.”

Doctors’ orders

Doctors caution that the health effects of cannabis on a fetus remain unclear but could include low birth weight and developmental problems, according to the US Centers for Disease Control and Prevention.

In animal studies, the active ingredient THC has been shown to cross the placenta, and researchers have suggested that it could cause “irreversible, subtle dysfunctions in the offspring.”

Still, experts say the science is still in progress, and human studies are primarily observational: “It is unethical to purposely expose women and their unborn babies to marijuana during pregnancy to study outcomes,” Mark said.

“Marijuana in pregnancy is … not as black and white as something like alcohol,” she added.

Though some dispensary employees did not make a recommendation in Metz’s study, some claimed that eating versus smoking cannabis products could make their products safer. Others recommended that the women not broach the subject with their doctors.

“Google it first. Then if you feel apprehensive about it, you could ask,” one employee told a researcher who posed as a pregnant customer.

“Maybe you have a progressive doctor that will not lie to you. All the studies done back in the day were just propaganda,” another employee said.

“It was hard to hear that, being a health care provider,” Metz said of employees’ unproven safety claims and recommendations that women not ask their doctors about it.

Metz and her colleagues wrote that there are no regulations in Colorado surrounding what recommendations and advice dispensaries can give to customers. Cannabis products in the state are, however, required to be labeled as follows: “There may be additional health risks associated with the consumption of this product for women who are pregnant, breastfeeding, or planning on becoming pregnant.”

The American College of Obstetricians and Gynecologists recommends that “women who are pregnant or contemplating pregnancy should be encouraged to discontinue marijuana use” and “to discontinue use of marijuana for medicinal purposes in favor of an alternative therapy.”

Additionally, “there are insufficient data to evaluate the effects of marijuana use on infants during lactation and breastfeeding, and in the absence of such data, marijuana use is discouraged,” according to the recommendations.

The journal in which the new study appeared is the official publication of the organization.

Metz said she hopes this study will “engage the cannabis industry … in really coming together in terms of what the reasonable message should be providing to pregnant women.”

“I think that the majority of women are really trying to do the right thing for their pregnancy and for their baby,” she added. “I just think we need to get that information to their hands.”

Overstepping boundaries

Prior research has suggested a rise in pregnant women using pot – sometimes to ease the nausea of morning sickness or heightened anxiety. The highest increase may be among women 24 and younger, according to a study of pregnant women in California in December.

There are conventional medications for morning sickness that are considered safe for pregnancy, such as vitamin B6 and doxylamine, an antihistamine sold under brands like Unisom. For some women, eating small, frequent meals and staying hydrated can help, Mark said.

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“My impression is that some women have a certain level of skepticism when it comes to the health care system,” she said, and that some might be “leery of taking ‘pharmaceuticals’ during pregnancy but view marijuana as a more ‘natural’ option.”

“Legalization does not equate to safety, particularly in pregnancy,” she said. “I actually think that the fact that dispensaries are providing any recommendations for treatment of medical conditions is very much overstepping appropriate boundaries.”

CNN’s Jacqueline Howard contributed to this report.