Using marijuana during pregnancy may cause harm to your baby and increase the risk of premature birth. It may also affect fertility before pregnancy. Learn about the effects of marijuana and, if, seek help to quit. Learn about whether marijuana can cause infertility, including a review of research on marijuana's effects on women and men. Interesting, if not conflicting, research has recently been published on the topic of marijuana and infertility. Here, our experts take a closer look.
Marijuana and pregnancy
No amount of marijuana has been proven safe to use during pregnancy.
Using marijuana during pregnancy may cause problems for your baby, like premature birth, problems with brain development and stillbirth.
It’s not safe to use marijuana to treat morning sickness. Talk to your health care provider about treatments that are safer for your baby.
If you use marijuana, don’t breastfeed. You may pass chemicals from marijuana to your baby through breast milk.
Talk to your provider if you need help to quit using marijuana or any other street drug.
What is marijuana?
Marijuana (also called pot, weed and cannabis) is a drug that comes from the dried leaves, flowers, stems and seeds of the cannabis plant. Marijuana is the most commonly used street drug during pregnancy.
Marijuana has more than 500 chemicals, including tetrahydrocannabinol (also called THC). This chemical can affect how your brain works and make it hard to think clearly. THC and other chemicals in marijuana may change your sense of sight, sound and touch.
Using marijuana during pregnancy may cause problems for your baby before and after birth.
What is medical marijuana?
Medical marijuana (also called medicinal marijuana) is sometimes used to treat certain health conditions, like cancer or severe pain. In many states, medical marijuana is legal to use with a recommendation from your health care provider. It can be smoked, vaped or eaten. The Food and Drug Administration (also called FDA) has not approved marijuana as a safe and effective medicine for any health condition.
In some states, marijuana is legal for personal use that’s not for medical reasons.
Even if it’s legal where you live for either personal or medical use, no amount of marijuana is safe to use marijuana during pregnancy, even to treat morning sickness. There is also no safe way to use marijuana. If you’re thinking of using marijuana to help with morning sickness, talk to your provider about other treatments that are less harmful to your baby.
Is it harmful to use marijuana before pregnancy?
Yes. Before pregnancy, using marijuana can affect your fertility and make it hard for you to get pregnant. Marijuana can affect:
- Hormones that your body needs to get pregnant. Hormones are chemicals made by the body.
- Your menstrual cycle. This is the process of your ovaries releasing an egg every month.
- A man’s sperm count (the number of sperm he makes). A man’s sperm fertilizes a woman’s egg to begin a pregnancy.
Can using marijuana during pregnancy cause problems for your baby?
Yes. When you use marijuana during pregnancy, THC and other chemicals can pass through the placenta to your baby. The placenta grows in your uterus (womb) and supplies your baby with food and oxygen through the umbilical cord. Chemicals from marijuana also may pass to your baby’s brain.
Researchers are continuing to study the effects of marijuana use during pregnancy. Women who use marijuana may smoke cigarettes, drink alcohol or use other street drugs, making it hard to know exactly how marijuana affects pregnancy. Some studies suggest that if you use marijuana during pregnancy, your baby may have problems, including:
. This is birth that happens too early, before 37 weeks of pregnancy.
- Fetal growth restriction (also called growth-restricted, small for gestational age and small for date) and low birthweight. Fetal growth restriction is when a baby doesn’t gain the weight she should before birth. Low birthweight is when a baby is born weighing less than 5 pounds, 8 ounces. Your baby also may have short body length or small head size.
- Anencephaly. This is one of the most severe neural tube defects (also called NTDs). NTDs are birth defects in the neural tube, the part of a developing baby that becomes the brain and spine. Babies with this condition are missing major parts of the brain, skull and scalp. Most do not survive long after birth, usually for just a few hours. Babies exposed to marijuana during the first month of pregnancy are at increased risk of having anencephaly. . This is when your baby doesn’t have enough healthy red blood cells to carry oxygen throughout the body.
- Problems with brain development. . This is when a baby dies in the womb after 20 weeks of pregnancy.
If you use marijuana during pregnancy, your baby can have problems after birth and may need to spend time in the neonatal intensive care unit (also called NICU). A NICU is the nursey in a hospital where sick newborns get care. These problems include:
- Withdrawal symptoms, like tremors (shakes), seizures, vomiting, slow weight gain or long periods of crying after birth. These symptoms usually go away within the first two weeks after birth.
- Problems with sleeping.
- Problems with behavior, memory, learning, problem-solving, depression and paying attention.
How does using marijuana affect breastfeeding?
If you breastfeed your baby and smoke marijuana, you may pass THC and other chemicals to your baby through the breast milk. Than can make your baby more likely to have problems with brain development. Marijuana also may affect the amount and quality of breast milk you make. The American Academy of Pediatrics recommends that breastfeeding moms stay away from marijuana to help keep breast milk safe and healthy.
Can using marijuana harm your general health?
Yes. The more marijuana you use, the more likely you are to have problems, including:
- Very fast heart rate
- Lung problems, including bronchitis and chronic cough (like a smoker’s cough)
- Trouble paying attention or thinking clearly
- Memory problems
- Trouble sleeping
- Clumsiness and poor coordination and balance
How can you get help to quit using marijuana?
Talk to your health care provider. He can help you get treatment to quit. Or contact:
How Marijuana Can Affect Fertility
Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.
Verywell Mind articles are reviewed by board-certified physicians and mental healthcare professionals. Medical Reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more.
Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital.
Although the link between marijuana and fertility is not straightforward—plenty of marijuana smokers get pregnant and get their partners pregnant—some research has demonstrated that marijuana use can negatively impact you, your partner, or the fertility of both of you.
Research suggests that marijuana can negatively affect female fertility in the following ways:
- Decreases libido. Even before intercourse takes place, marijuana use may decreases libido. And if you aren’t feeling in the mood, it’s that much more difficult to get started.
- Increases the risk of miscarriage. Marijuana use also increases the risk of miscarriage. Marijuana is known to cross the placenta and may pose a risk to the fetus, although the effects of marijuana exposure in the womb are not as well documented as the effects of alcohol and some other drugs.
Furthermore, the effects of marijuana on fertility seem to accumulate over time. This means that although teenage girls who smoke marijuana are more likely to get pregnant, by the time a chronic marijuana smoking woman is in her mid-twenties, she may be more likely to experience a delay in getting pregnant.
Despite the relaxation effects that many people associate with marijuana use, research has shown marijuana has negative effects on the male sexual response.
- Increases impotence. Cannabis use has been associated with sexual dysfunction, which can also have negative effects on the male ego. If your partner has been impotent, he may be feeling more pressure to have sex to get you pregnant, but be frustrated with his inability to do so. This can lead to misunderstandings between you that make it more difficult to have sex.
- May lead to premature ejaculation. Marijuana use has been associated with premature ejaculation.
- May decrease sperm count. A regular smoker of marijuana has a risk of having a lower sperm count.
- Affects sperm structure and function. Additionally, the sperm produced by marijuana smoking has been associated with abnormal morphology (shape) and motility (its ability to “swim” and fertilize the egg).
Quit to Prepare for Parenthood
Obviously, if you are both smoking marijuana, you risk increasing the chances of infertility as a couple.
Quitting marijuana can be harder than many long-term marijuana users expect, so you and your partner would be wise to quit as soon as possible, while you still have time to get help before getting pregnant. If either or both parents still use marijuana when the baby arrives, you are increasing the risk that your child may use drugs in the future, and parental drug use is implicated in many difficulties for children and families.
Your family doctor can help you with a referral to a counselor or clinic that can help you both quit. Couples counseling, which is offered by many addiction clinics, would be particularly helpful at this time. If you are already engaged in infertility treatment, coming clean about your marijuana could save you a lot of time, money, and heartache, if marijuana is one of the culprits for your difficulties with conception.
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Bari M, Battista N, Pirazzi V, Maccarrone M. The manifold actions of endocannabinoids on female and male reproductive events. Front Biosci (Landmark Ed). 2011;16:498-516. doi:10.2741/3701
By Elizabeth Hartney, BSc, MSc, MA, PhD
Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.
Marijuana and Infertility: What You Need to Know
All information on this website is for general informational purposes only and is not intended or implied to be a substitute for professional medical advice, diagnosis or treatment.
For decades, there has been an ongoing discussion regarding cannabis and infertility. Numerous anecdotal outlets have cited decreased fertility rates among cannabis users (especially a decline in sperm count in males), but is there any clinical or scientific evidence to back up these claims?
In this article, we discuss relevant contemporary research relating to the topic. We’ll also discuss whether “marijuana infertility” is truly a concern. Read on to find out more.
Does Marijuana Cause Infertility?
There is a body of evidence suggesting that marijuana causes infertility. However, even more concerning is relatively recent research that suggests that fertility, especially in males — may be declining overall.
A study published in Human Reproductive Update in 2017 identified a potentially key issue. It looked at 7,500 studies performed from 1973 to 2011. The researchers found that men from Australia, New Zealand, Europe, and North America had an almost 60% decline in sperm count. They also had a sperm concentration decline of 52%.
Researchers offered several hypotheses attributed to the decline in semen quality. These include:
- Increase exposure to pesticides
- Meta-changes in diet
- Exposure to higher-temperature climates
- Meta-changes in Body Mass Index (BMI)
- Other lifestyle/environmental factors
A major underlying concern, particularly given evidence that cannabis use is on the rise (as well as evidence that smoking tobacco affects fertility), is whether or not marijuana causes infertility. Another is whether cannabis use may have a variable impact on males’ and females’ fertility and reproduction potential.
Potential Impact of Cannabis Use on Female Fertility
Data regarding the relationship between female infertility and marijuana use is limited. However, a study published in the Journal of Women’s Health in 2016 suggests that smoking cannabis can delay a woman’s ovulation by several days.
Furthermore, a separate study published by the National Institute on Drug Abuse suggests that cannabinoids can alter hormone secretion related to reproductive function. Authors suggest that cannabinoids, specifically THC, can “inhibit secretion of LH, FSH, [and] prolactin,” resulting in “decreases in sex steroid hormones [as well as] changes in ovulation.”
However, the researchers observed that these effects are reversible when cannabis use is ceased.
Still, most experts recommend that pregnant women and women who are considering becoming pregnant – avoid the use of cannabis altogether both during and before pregnancy. This recommendation is more pressing than ever, as cannabis use among young reproductive-aged women is rising.
In fact, according to currently available statistics, upwards of 8% of non-pregnant reproductive-aged women use cannabis on a relatively consistent basis. As authors of the above publication observe, “prenatal marijuana exposure [can be] associated with poor offspring outcomes,” including an increased prevalence of conditions like low birth weight and impaired brain development.
What About Male Fertility? Does Cannabis Reduce Sperm Count?
Another pressing concern – and an ongoing topic of debate circulating for decades – is whether or not marijuana can cause male infertility.
A study published in the American Journal of Epidemiology in 2015 appears to suggest that it can. The study observed over 1,200 Danish men aged 18-28, 45% of which had smoked cannabis in the previous three months. Twenty-eight percent of study participants used marijuana more than once a week. The study discovered that those who used cannabis regularly had a 29% reduction in sperm count.
The answer may shock you!…
However, a study published in Human Reproduction in 2019 appears to contradict the research above. This study, which took place over 17 years from 2000 to 2017, examined 1,100 semen samples from male patients enrolled in the Massachusetts General Hospital Fertility Center. The study found that cannabis users had a higher sperm count per milliliter of ejaculate (62.7 million sperm compared to 45.4 million in non-cannabis users). Only 5% of cannabis-using test subjects had sperm count levels considered low (below 15 million per milliliter).
Based on the availability of contemporary research data, the impact of cannabis use on male fertility is still largely inconclusive.
Additional Research on Weed and Infertility
Another interesting publication on the broader topic of weed and infertility appeared in 2018 in the peer-reviewed academic journal Fertility and Sterility.
In the study, researchers analyzed nearly 2,000 male and female participants that were trying to conceive. Eleven-and-a-half percent of women admitted to using cannabis during this period, along with 16.5% of men. The study results suggested that cannabis use did not have a negative impact on the time it took for couples to become pregnant.
Again, however, it is highly recommended that cannabis use be avoided among individuals trying to conceive.
Bottom Line on Marijuana and Infertility
The general discrepancy in the observations made from these above-referenced studies means we can’t draw any firm conclusions regarding the ongoing debate of marijuana and infertility. Without a doubt, more research needs to be done on the topic.
Unfortunately, there are still challenges associated with carrying out quality cannabis-based research.
At present, cannabis is only fully legal (on a national level) in Canada and Uruguay. This means that federal research funding for cannabis studies is still difficult for many global research organizations.
Regardless of whether or not marijuana causes infertility, it is best to avoid the consumption of cannabis altogether for those trying to conceive. Likewise, pregnant women should always steer clear of any form of cannabis use.