SAN JOSE, Calif. — On many mornings, with a few puffs of pot — and one cannabis-laced chocolate-covered blueberry in the afternoon — Richelle has been able to stop the severe nausea that has accompanied her third pregnancy.

The regimen not only ended the constant vomiting, but the San Jose mother can now finally eat an entire cheeseburger — and keep it down.

“The medical field frowns on pregnant women using marijuana,” said the 27-year-old bookkeeper, who lost 30 pounds early on in her pregnancy because of her condition, called hyperemesis gravidarum, which also causes dehydration.

“But I possibly would not have kept the pregnancy without it,” said Richelle, who is now in her 25th week and asked that her last name not be used because she does not want to be publicly attacked for her beliefs.

After two decades of allowing its medicinal use, California is now one of eight states that have legalized recreational marijuana for people 21 and older. Public health officials, however, say the implications surrounding its consumption by some people — like pregnant women and adolescents, who may be more vulnerable to its potential harmful effects — still must be addressed.

Some states — including Alaska, Washington and Colorado — require warning labels saying the product should not be used by pregnant or breastfeeding women. But California does not.

Concerns

Surveys show that most Americans don’t like the idea of pregnant women using marijuana.

A Yahoo News/Marist College poll of 1,222 adults released this month found that 67 percent of Americans think it’s safer to use marijuana than opioids to relieve pain. But 69 percent said it’s not acceptable for pregnant women to use marijuana to reduce nausea or pain. Half of cannabis users — and 60 percent of those who have tried it — also don’t think pregnant women should use marijuana, according to the poll.

Dr. Ira Chasnoff, a professor of clinical pediatrics at the University of Illinois College of Medicine and a leading researcher in the development of children prenatally exposed to alcohol and drugs, said a range of studies supports those concerns.

“The general belief is that it’s not harmful,” Chasnoff said of cannabis consumption. “But there are all sorts of aspects of cognitive function — the way the brain works — that are impacted by marijuana exposure.”

He pointed to research that shows low birth rates in babies born to women who have consumed pot during pregnancy, as well as data on higher rates of Attention Deficit Disorder and Attention Deficit Hyperactivity Disorder as they get older. Other research has shown that those offspring later in life have problems with “executive functioning,” or the ability to plan and complete tasks, Chasnoff said.

That’s why he believes guidelines that communicate the risk and discourage the use of medical marijuana by pregnant women — or women considering pregnancy — must be established. Research indicates that more U.S. women are now using marijuana during pregnancy, most often to treat morning sickness — which most physicians say can be better treated with more established medications.

A recent study in the Journal of the American Medical Association said that in 2014 nearly 4 percent of pregnant women between the ages of 18 and 44 reported having used marijuana in the past month, compared with 2.4 percent in 2002.

In Oakland, 36-year-old Sarah — who runs a cannabis consulting business with her husband — said she has been using the drug during her 17-week pregnancy to help not only with morning sickness but also with sciatica pain and mood swings.

Like Richelle, she takes a few puffs of a marijuana cigarette every so often, but also uses a few drops of liquid cannabis on her tongue at night. The pain disappears, she said, and she’s able to keep food in her stomach.

Unconvinced

She has read a host of studies on the potential side effects the drug might have on her baby. So have some of her relatives, who have told her that using marijuana will “risk having my child come out dumb,” said Sarah, who also said she didn’t want her last name published because she fears she’ll be ostracized.

But she remains unconvinced by what she calls “limited research.” And she says that she doubts that an organically grown plant could harm her baby.

A landmark 395-page study on the health effects of cannabis and cannabinoids released in January by the National Academies of Sciences, Engineering and Medicine also wasn’t able to draw many conclusions.

After reviewing the available research, the authors determined that the long-term effects of smoking cannabis during pregnancy are still unclear. But they did agree that there is substantial evidence that the babies of women who smoke marijuana while pregnant have lower birth weights.

Sarah says she doesn’t abuse the drug but believes it helps to reduce the anxiety that comes with being pregnant. “There is a human inside me growing, and everyone is telling me what I can and cannot do,” she said. “It creates a lot of worry.”

And in her line of work, she has also met many women who used marijuana when they were pregnant and whose children — of all ages — seem well-adjusted.

“Everything in moderation,” Sarah said.