Dear Doctor: I read that more women are using marijuana for morning sickness. This doesn't seem like a good idea, but for women with severe morning sickness, might it be an option? Could it really hurt the baby?

Dear Reader: Marijuana refers to the flowering annual Cannabis sativa. It's a complex plant packed with phytochemicals with a number of potential (and one recently FDA-approved -- we'll get to that in just a moment) medical applications. While it's true that smoking cannabis has been shown to ease nausea, when it comes to morning sickness, we do not recommend it. Cannabis remains illegal at the federal level, and at the state level is subject to a tangled and often conflicting patchwork of regulations. That means many of its prospective medical applications have not yet undergone the robust and rigorous study needed to ascertain efficacy, safety and dosage parameters.

For women considering smoking or ingesting cannabis while pregnant, it's important to understand that the placenta allows its psychoactive component, tetrahydrocannabinol, or THC, to reach the developing fetus. Some research has put the amount at 10 percent of what the mother receives, a concentration that rises with repeated use. Some studies have suggested a link between cannabis use in pregnant women with low birth-weight babies and impaired neurological development. As we said earlier, medical research into cannabis is in its infancy. Until we have a better understanding of the outcomes of its use during pregnancy, the recommendation from the American College of Obstetricians and Gynecologists is that women who are pregnant, as well as those who plan to be, should not use cannabis.

Switching gears, we heard from many of you after the publication of the column about CBD, or cannabidiol. CBD is one of over 100 cannabinoids found in Cannabis sativa and unlike THC, is not psychoactive. CBD has been shown to have analgesic, anti-inflammatory, anti-seizure and anti-anxiety properties, and has great therapeutic potential. We stated that despite the explosion of CBD products now available, none were FDA-approved.

At the time we wrote the column, this was indeed true. However, several weeks later -- and thank you to everyone who wrote in with updates and clarifications -- the first CBD medication received FDA approval. Called Epidiolex, it's a treatment for seizures associated with Lennox-Gastaut syndrome and Dravet syndrome, two rare and severe forms of epilepsy. The former begins between ages 3 and 5, and the latter begins in infancy. Epidiolex is the first FDA-approved use of CBD, and the only treatment for Dravet syndrome to get FDA approval.

Since cannabis remains a controlled substance, the Drug Enforcement Administration must also provide regulatory approval for Epidiolex. Once the DEA schedules its use, the question of availability moves to the state level. Many small pharmacies and at least one national chain, Rite Aid, have already stated that they will stock and sell the drug once it has cleared all regulatory hurdles. The drug, created by the British company GW Pharmaceuticals, will be manufactured in England and exported to the United States. Because Epidiolex is an FDA-approved pharmaceutical, only stores with pharmacy licenses will be allowed to sell it.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Does getting a bikini wax really increase the risk of getting a sexually transmitted disease? How would someone figure that out?

Dear Reader: Whether it's a bit of a trim for swimsuit season or the more extreme forms of waxing that leave you completely bare down there, millions of women (and a few men) engage in some type of pubic hair grooming. Now the results of new research that looked into the practice suggest that, for people who are sexually active, pubic grooming may make it easier to contract a sexually transmitted infection, or STI.

It sounds more than a little alarming, so we'll start by citing the lead investigator, an assistant professor of surgery at the University of Texas, who stated that while the study did reveal a correlation, it does not equal proof. The title itself uses the language "representative probability sample." That translates only to "if ... and," not to the certainty of "if ... therefore" when it comes to pubic grooming and STIs.

The researchers began with two statements -- STIs are the most common infections among adults, and many adults take part in trimming or outright removing some or all of their pubic hair. (Considering the millions of cases of influenza reported each year, we confess that we were skeptical about the first statement. But STIs encompass a wide range of infections. Digging into statistics kept by the federal Centers for Disease Control and Prevention -- 14 million new cases of human papillomavirus, or HPV, per year; 1.4 million new cases of chlamydia annually, to name just two types of STI -- backed it up.)

The next step was a probability survey in which a group of U.S. residents between the ages of 18 and 65 were asked about pubic grooming habits, sexual activity and STIs. Extreme grooming was defined as having all pubic hair removed 11 or more times per year. Trimming pubic hair either weekly or daily was considered to be high-frequency grooming. STIs and pubic lice were tracked separately. A total of 7,580 people completed the questionnaires. The results, when analyzed, pointed to a correlation (again, an apparent connection, not a direct cause) between pubic grooming and STIs.

Among the respondents to the questionnaire, 84 percent of the women and 66 percent of the men reported taking part in some type of pubic grooming. Those who reported pubic grooming were 80 percent more likely to also report having dealt with an STI, according to the findings. A higher frequency of pubic grooming translated to a higher incidence of STIs. For those in the extreme grooming category, the link between the behavior and STIs was quadruple that of non-groomers. Interestingly, even those who simply trimmed their pubic hair had an uptick in STI reporting. Not part of the study was condom use, or time intervals between grooming, sex and STIs, all of which could affect the results.

As for what may be going on, the researchers posed two theories. One is that pubic grooming may cause microtears and abrasions in the skin that create multiple new pathways for pathogens to enter the body. The other is that the groomers were more sexually active than the non-groomers. The survey results were intriguing enough that more research is forthcoming.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: Could working too much actually give me an irregular heartbeat later in life as a study I heard about suggests? I'm 55 and run my own tech support business, so I keep some really long and often irregular hours.

Dear Reader: The image of the "Type A" person who devotes long hours to the job has long been cemented into the national lexicon. The fact that this driven, goal-oriented temperament is considered admirable, if not an outright attribute, says a lot about us as a nation of workers. But the results of a recent study remind us that this kind of single-mindedness can come at a price.

Previous research has connected long working hours to an increased risk of having a stroke or developing coronary artery disease. Now, according to a paper published in the European Heart Journal last summer, people who work 55 hours or more per week also have a greater chance of experiencing atrial fibrillation as the years go on. This irregular heartbeat, which feels fluttery and is often quite rapid, means the electrical signals that prompt the heart have gone haywire. Rather than a controlled rhythm and sequence that allows the upper chambers of the heart to move blood as efficiently as possible, AFib is an ineffectual spasm that is associated with a rise in the risk of heart-related complications and stroke.

In this study, researchers looked at health data from about 85,500 working women and men from Finland, Denmark, Sweden and the United Kingdom. None of the study participants had a history of atrial fibrillation. As each participant entered the study, the number of hours that they worked per week was noted. At the end of about 10 years, each study participant was evaluated again. Using data collected from electrocardiograms, hospital and pharmacy records, as well as death certificates, researchers found 1,061 new cases of atrial fibrillation. For the group as a whole, this translated to 12.4 new cases of AFib per 1,000 people. However, when researchers looked at study participants who spent long hours at work, the incident rate rose to 17.6 new cases of AFib per 1,000 people. That's an increased risk of 40 percent, according to the statistical analysis in the study.

Studies like this, which identify outcomes based on analysis of selected behaviors, point out a correlation. They do not suggest that the behavior is the cause. In the case of the participants who spent 55-plus hours working, lifestyle issues may have also played a role in their health outcomes. Not only did people who worked a lot report more depression and anxiety at the start of the study, they were more likely to be overweight, spend less time in leisurely pursuits, and reported more tobacco and alcohol use.

If your own work habits give you cause for concern, step back and see what you can change. You may not be able to cut your hours, but adding meditation and deep breathing into your daily routine can help with stress. Having a better diet, cutting out tobacco and adding regular exercise will also add to your overall quality of life.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)