Pregnant and breastfeeding women should probably be advised to either decrease, or where possible, cease cannabis use entirely. And, couples trying to conceive may also want to consider cutting down.
The Effects of Marijuana on Fertility and Pregnancy
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Approximately one in six couples “are unable to conceive after a year,” despite trying, “and are labeled infertile.” And in up to half the cases, it may be the man’s fault. There are “several lifestyle factors [that] have been associated with [diminished] sperm production,” such as smoking cigarettes. But what about smoking marijuana?
“Regular marijuana smoking more than once per week was associated with [about] a 28 percent …lower sperm concentration and…lower total sperm count,” based on a study of more than a thousand men. But “no adverse association was found for irregular use,” meaning less than once a week.
Now, this wasn’t a randomized study. And so, there may have been other factors that go along with regular marijuana use that could have really been to blame. But, they took into account cigarettes and alcohol and other drugs and STDs and things like that. But, there’s always a possibility there was something else for which they didn’t control.
Findings were similar for women. Hundreds of infertile couples were studied in California, and just like men had about a quarter fewer sperm, a quarter fewer eggs were retrieved from women using cannabis more than 90 times in their lifetime, or using the year before. Again, there could have been confounding factors, but until we know more, couples that are trying to conceive may want to make the joint decision to turn over a new leaf.
What about during pregnancy? Medical authorities recommend that women even “contemplating pregnancy should be encouraged to discontinue marijuana use,” and not use during pregnancy or lactation, though the Academy of Breastfeeding Medicine suggests the known benefits of breastmilk currently outweigh any potential harms for women who continue to smoke it. Despite these warnings from authorities, marijuana use has increased among pregnant women in recent years, up 60 percent. But that’s only from about 2.5 percent up to less than 4 percent, less than half the frequency of non-pregnant women.
Why are OB/GYNs so down on getting high? You’ll see scary articles in the American Journal of Obstetrics and Gynecology, making claims like this: a large study supposedly documenting a significantly increased risk for a serious birth defect. But, if you don’t just take their word for it, and pull up the actual study, you’ll see that the association wasn’t statistically significant after all. “Objective education [about marijuana and pregnancy] is good, but biased education is not.”
There have been some risks identified: infants may be “more likely to be [born] anemic, [or] have a lower birth weight, [or] require…intensive care,” compared to infants of mothers who do not use marijuana. But it’s “difficult to determine the direct effects of maternal cannabis use on the developing fetus because of” a variety of confounding factors, for which studies may not be able to completely control.
“Studies have also shown links between prenatal marijuana exposure and” learning problems later in life, manifesting years later at school, and that’s really where the greater concern lies: the potential long-term effects on brain development. So, even after weeding out the myths, there is enough concern that “pregnant and breast feeding [women] should [indeed probably] “be advised to either decrease or where possible cease cannabis use entirely.”
Please consider volunteering to help out on the site.
- Eisenberg ML. Invited Commentary: The Association Between Marijuana Use and Male Reproductive Health. Am J Epidemiol. 2015;182(6):482-4.
- Gundersen TD, Jørgensen N, Andersson AM, et al. Association Between Use of Marijuana and Male Reproductive Hormones and Semen Quality: A Study Among 1,215 Healthy Young Men. Am J Epidemiol. 2015;182(6):473-81.
- Klonoff-cohen HS, Natarajan L, Chen RV. A prospective study of the effects of female and male marijuana use on in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) outcomes. Am J Obstet Gynecol. 2006;194(2):369-76.
- Foeller ME, Lyell DJ. Marijuana Use in Pregnancy: Concerns in an Evolving Era. J Midwifery Womens Health. 2017;62(3):363-367.
- Brown QL, Sarvet AL, Shmulewitz D, Martins SS, Wall MM, Hasin DS. Trends in Marijuana Use Among Pregnant and Nonpregnant Reproductive-Aged Women, 2002-2014. JAMA. 2017;317(2):207-209.
- Chasnoff IJ. Medical marijuana laws and pregnancy: implications for public health policy. Am J Obstet Gynecol. 2017;216(1):27-30.
- Van gelder MM, Reefhuis J, Caton AR, et al. Maternal periconceptional illicit drug use and the risk of congenital malformations. Epidemiology. 2009;20(1):60-6.
- Torres CA, Hart CL. Marijuana and pregnancy: objective education is good, but biased education is not. Am J Obstet Gynecol. 2017;217(2):227.
- Volkow ND, Compton WM, Wargo EM. The Risks of Marijuana Use During Pregnancy. JAMA. 2017;317(2):129-130.
- Jaques SC, Kingsbury A, Henshcke P, et al. Cannabis, the pregnant woman and her child: weeding out the myths. J Perinatol. 2014;34(6):417-24.
Image credit: Jenna Norman via unsplash. Image has been modified.
Motion graphics by Avocado Video
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
Approximately one in six couples “are unable to conceive after a year,” despite trying, “and are labeled infertile.” And in up to half the cases, it may be the man’s fault. There are “several lifestyle factors [that] have been associated with [diminished] sperm production,” such as smoking cigarettes. But what about smoking marijuana?
“Regular marijuana smoking more than once per week was associated with [about] a 28 percent …lower sperm concentration and…lower total sperm count,” based on a study of more than a thousand men. But “no adverse association was found for irregular use,” meaning less than once a week.
Now, this wasn’t a randomized study. And so, there may have been other factors that go along with regular marijuana use that could have really been to blame. But, they took into account cigarettes and alcohol and other drugs and STDs and things like that. But, there’s always a possibility there was something else for which they didn’t control.
Findings were similar for women. Hundreds of infertile couples were studied in California, and just like men had about a quarter fewer sperm, a quarter fewer eggs were retrieved from women using cannabis more than 90 times in their lifetime, or using the year before. Again, there could have been confounding factors, but until we know more, couples that are trying to conceive may want to make the joint decision to turn over a new leaf.
What about during pregnancy? Medical authorities recommend that women even “contemplating pregnancy should be encouraged to discontinue marijuana use,” and not use during pregnancy or lactation, though the Academy of Breastfeeding Medicine suggests the known benefits of breastmilk currently outweigh any potential harms for women who continue to smoke it. Despite these warnings from authorities, marijuana use has increased among pregnant women in recent years, up 60 percent. But that’s only from about 2.5 percent up to less than 4 percent, less than half the frequency of non-pregnant women.
Why are OB/GYNs so down on getting high? You’ll see scary articles in the American Journal of Obstetrics and Gynecology, making claims like this: a large study supposedly documenting a significantly increased risk for a serious birth defect. But, if you don’t just take their word for it, and pull up the actual study, you’ll see that the association wasn’t statistically significant after all. “Objective education [about marijuana and pregnancy] is good, but biased education is not.”
There have been some risks identified: infants may be “more likely to be [born] anemic, [or] have a lower birth weight, [or] require…intensive care,” compared to infants of mothers who do not use marijuana. But it’s “difficult to determine the direct effects of maternal cannabis use on the developing fetus because of” a variety of confounding factors, for which studies may not be able to completely control.
“Studies have also shown links between prenatal marijuana exposure and” learning problems later in life, manifesting years later at school, and that’s really where the greater concern lies: the potential long-term effects on brain development. So, even after weeding out the myths, there is enough concern that “pregnant and breast feeding [women] should [indeed probably] “be advised to either decrease or where possible cease cannabis use entirely.”
Please consider volunteering to help out on the site.
- Eisenberg ML. Invited Commentary: The Association Between Marijuana Use and Male Reproductive Health. Am J Epidemiol. 2015;182(6):482-4.
- Gundersen TD, Jørgensen N, Andersson AM, et al. Association Between Use of Marijuana and Male Reproductive Hormones and Semen Quality: A Study Among 1,215 Healthy Young Men. Am J Epidemiol. 2015;182(6):473-81.
- Klonoff-cohen HS, Natarajan L, Chen RV. A prospective study of the effects of female and male marijuana use on in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) outcomes. Am J Obstet Gynecol. 2006;194(2):369-76.
- Foeller ME, Lyell DJ. Marijuana Use in Pregnancy: Concerns in an Evolving Era. J Midwifery Womens Health. 2017;62(3):363-367.
- Brown QL, Sarvet AL, Shmulewitz D, Martins SS, Wall MM, Hasin DS. Trends in Marijuana Use Among Pregnant and Nonpregnant Reproductive-Aged Women, 2002-2014. JAMA. 2017;317(2):207-209.
- Chasnoff IJ. Medical marijuana laws and pregnancy: implications for public health policy. Am J Obstet Gynecol. 2017;216(1):27-30.
- Van gelder MM, Reefhuis J, Caton AR, et al. Maternal periconceptional illicit drug use and the risk of congenital malformations. Epidemiology. 2009;20(1):60-6.
- Torres CA, Hart CL. Marijuana and pregnancy: objective education is good, but biased education is not. Am J Obstet Gynecol. 2017;217(2):227.
- Volkow ND, Compton WM, Wargo EM. The Risks of Marijuana Use During Pregnancy. JAMA. 2017;317(2):129-130.
- Jaques SC, Kingsbury A, Henshcke P, et al. Cannabis, the pregnant woman and her child: weeding out the myths. J Perinatol. 2014;34(6):417-24.
Image credit: Jenna Norman via unsplash. Image has been modified.
Motion graphics by Avocado Video
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The Effects of Marijuana on Fertility and Pregnancy
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When do I mean cut down “when possible?” Check out my video Natural Treatments for Morning Sickness to see how sometimes marijuana use during pregnancy can be a lifesaver.
I’m winding down to the last few marijuana videos, which I originally released in a webinar and downloadable digital DVD. There are still a few coming out over the next year, but if you missed any of the published ones, here they are:
- The Institute of Medicine Report on the Health Effects of Marijuana
- Researching the Health Effects of Marijuana
- Is Marijuana Addictive?
- Does Marijuana Cause Health Problems?
- Does Marijuana Cause Permanent Brain Damage in Teens?
- Does Marijuana Cause Permanent Brain Damage in Adults?
- Will Cannabis Turn Into Big Tobacco?
- Marijuana Legalization & the Opioid Epidemic
- Effects of Smoking Marijuana on the Lungs
- Smoking Marijuana vs. Using a Cannabis Vaporizer
- Does Marijuana Cause Lung Cancer?
- Can Cannabis Cure Cancer?
- Are Cannabis Edibles Safe?
- Pesticides in Marijuana
For more on fertility, check out Male Fertility & Diet and Dairy Estrogen & Male Fertility.
What is The Trade-Off Between Fertility and Longevity, and Causes of Precocious Puberty? Check out the video.
I have another webinar coming up on fasting for weight loss, and probably a second one later this year because there’s just so much to cover. I love the opportunity to present a whole bunch of information on one topic all at once. For information on the fasting webinar, go here. As always, webinars will be broken into individual videos and released at no cost over the course of the year here on NutritionFacts.org.
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