The use of cannabis is most frequent in women between the ages of 20 and 30. This corresponds to the peak childbearing years. Since the potency of cannabis has increased and, with legalization, so has consumption of cannabis, there is increased cause for concern about the safety of using marijuana during pregnancy.
One of the great benefits of cannabis legalization is that researchers can now legally study the effects of the substance on animals and on humans. It is well known that the fetus is forming its major organs very early in pregnancy, often before a woman may suspect that she is pregnant. It is during this time that the fetus is particularly susceptible to anything that could impact its development.
Many people have the mistaken belief that marijuana, because it is a more “natural” substance than man-made medications, is naturally less likely to be harmful. A recent study indicated that about 11% of women in northern California used cannabis for nausea during pregnancy. Many women, lay healers, cannabis dispensaries, and even some health care providers may believe that since marijuana is effective for decreasing chemotherapy-induce nausea, it must also be good for relieving morning sickness during pregnancy. While it may have an effect (though no studies have determined this to be true), it may come at a cost to the developing infant.
We know that there are cannabinoid-1 (CB1) receptors in the placenta. We know that cannabinoids cross the placenta and enter the blood circulation of the fetus.
Findings from recent research on animals suggest that cannabinoids may inhibit fetal liver enzymes and decrease dopamine receptors in the developing fetal brain which might cause cognitive impairment.
It is difficult to evaluate the effects of substances used during pregnancy in humans, (for example, you couldn’t ethically design a study that gives cannabis at different doses to pregnant women to see how their babies turn out) so we must rely on animal data to inform ourselves of potential dangers.
Research studies in animals have found similarities between the effects of alcohol and the effects of cannabis on the growing fetus. Defects in the head, face, and brain found in fetuses exposed to alcohol are also being seen in fetuses exposed to cannabis. The damage appears to be higher with higher doses of cannabis. These defects can result in the emotional, cognitive, and behavioral issues common in children with Fetal Alcohol Syndrome (FAS).
Researchers have also found that cannabis can increase the negative effects of alcohol; together cannabis and alcohol are suspected to be even more disruptive to a developing fetus than either one alone. Both alcohol and synthetic cannabis (Spice, K2, Fake Weed, etc.) are known to cause birth defects; researchers are finding that plant-based THC and perhaps CBD may result in more subtle but similar effects.
Clinical studies in humans have not definitively determined that marijuana use during pregnancy causes damage to a developing baby. But animal studies suggest that it might. The animal studies are clear – there is a strong biological probability, and a clear mechanism of action for potential long term neurological impairment.
Because there are alternative medications and other treatments that we know are safe to use for many of the discomforts of pregnancy and concomitant illnesses, the best advice for pregnant women is to refrain from using recreational or medicinal or synthetic marijuana during pregnancy. As always, it is prudent to seek advice from specialists in obstetrics before taking any substance during pregnancy.
Yes, THC is found in human milk. There is a large variation from one woman to another in the amount of THC is found in their breastmilk; the average is a relatively low amount (at about 2%). Of course, this would vary based on the dosage consumed and each woman’s metabolism. The concentration is highest in the first hour and the active metabolites are usually gone after a few hours. THC may be detected up to 6 days after ingestion.
The American Academy of Pediatrics section on breastfeeding states that, “…cannabis can be detected in human milk, and [its] use by breastfeeding mothers is of concern, particularly with regard to the infant’s long-term neurobehavioral development, and thus [is] contraindicated.”
We need more and better data before we can say that recreational cannabis can be used without risk during breastfeeding. Breastmilk is known to provide important components for infants’ growth and immune system, so any amount of time spent breastfeeding is beneficial. Lactating women should at least space feedings away from times of cannabis ingestion or bottle feed at such times. Women who are heavy users may want to consider infant formula. As in pregnancy, more thoroughly tested medicines can likely replace medicinal cannabis for women who are using medical marijuana for physical illness, mental disorders, or pain.
Insomnia is a very common health issue and its prevalence is increasing. Women identify insomnia as a problem more frequently than men. One study found the 63 percent of women and 54 percent of men reported struggling to attain restful sleep. Insomnia is one of the most common health-related conditions for which people seek to use medical marijuana and CBD.
Because THC and CBD are known to affect the regulation of anxiety, mood, autonomic function, and the circadian sleep cycle vis the endocannabinoid system, their application to sleep disorders is growing. Unfortunately, because of the legal issues, research in this area, like other areas, has been significantly delayed and is just now being undertaken in a systematic way. Most of the evidence we have to date comes from small studies, observational or survey research, or anecdotal data. Therefore, we can’t say with great confidence that cannabinoids are the solution to insomnia. However, there is promising preliminary evidence that they may be effective and that larger and more rigorously controlled studies are needed and should be done.
Preliminary research suggests that cannabidiol (CBD) may have therapeutic potential for the treatment of insomnia and that THC may be helpful in some circumstances but when used over a long period of time may impair sleep.
Insomnia is most commonly divided into three types:
- Inability to fall asleep
- Inability to stay asleep through the night
- Inability to get back to sleep after waking early in the morning
Some people have no idea why they are experiencing sleep problems, but more often than not, sleep disturbance is due to other causes, rather than a primary condition.
Sleep disturbance is often caused by pain. Over 20% of adults report suffering from chronic pain. This number is expected to increase as the U.S. population ages. Some evidence that Sativex, a 1:1 THC/CBD compound and the synthetic cannabinoid, nabilone, may be effective in combating both pain and sleep disturbance.
Other common causes of sleep disorders include obstructive sleep apnea (OSA) which affects about 9% of American adults. Early studies indicate that synthetic THC (dronabinol) may be effective against OSA-related sleep disruption.
REM behavior disorder in Parkinson’s disease – loss of muscle rigidity during REM sleep, nightmares, and acting out behaviors linked to dreams. Found high-dose CBD may suppress the behavioral response to nightmares and improve sleep. More research is needed.
Similarly, nightmares often occur in people with post-traumatic stress disorder (PTSD). Preliminary findings indicate that THC and the synthetic THC nabilone reduced the occurrence and intensity of nightmares and increased time asleep.
Excessive daytime sleepiness (EDS) usually has an underlying cause such as medications, medical conditions, mental health issues, sleep disorders like narcolepsy, or OSA. Its severity ranges from mild to extreme and negative consequences may include behavioral changes, attention deficits, memory interference, frustration, increased anxiety and rumination, and immune impairment.
For some users, the THC itself can be an underlying factor in insomnia. While THC may initially help with falling asleep, long term chronic use may lead to habituation (the same dose has less effect than it used to) which may lead to the use of more frequent and higher doses which can increase the risk for developing cannabis use disorder (CUD).
As with many medications, CBD and THC concentrations, dose, route of administration and timing of administration may all affect success. Studies suggest that CBD at a low dose has a stimulating effect and is associated with increased wakefulness, while high dose CBD increases total sleep time and decreased frequency of arousal at night. For some, CBD may improve sleep quality because of its anxiolytic effect.
There is a potential therapeutic effect of high dose CBD and low-dose THC for sleep.
Other promising findings:
- Synthetic cannabinoids like nabilone and dronabinol may have short-term benefit for sleep apnea
- Nabilone may reduce nightmares associated with PTSD and may improve sleep among patients with chronic pain.
- The synthetic cannabinoid HU211 is currently in clinical trials as a protective agent after brain trauma
- Patients taking nabilone for neurogenic pain reported actually preferring cannabis because they found it relieved not only pain but also depression and anxiety associated with chronic pain
We obviously still have a long way to go before we can definitively recommend cannabis and its derivatives for specific indications. It is an exciting time for cannabis research as the field is growing and there are many discoveries yet to be made. Our understanding of the endocannabinoid system and our identification of the therapeutic applications of cannabis is just beginning.