Study Links Marijuana Use During Pregnancy To Smaller Babies

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Smoking during pregnancy has been taboo for at least a generation or two now, but with more and more states legalizing marijuana researchers are finding it too can negatively impact a baby’s health.

Researchers from the University of Buffalo Research Institute on Addiction found that prenatal marijuana use can have consequences for a baby’s size and can influence behavior issues, especially if coupled with tobacco.

Marijuana Use During Pregnancy - The Everyday Mom Life

Published in the March/April issue of Child Development, the study looked at 250 infants and their mothers. In 173 of the cases the infants had been exposed to tobacco and/or marijuana during pregnancy. None were exposed to substantial amounts of alcohol.

“Nearly 30 percent of women who smoke cigarettes during pregnancy also report using marijuana,” says Rina Das Eiden, PhD, RIA senior research scientist in an interview with Science Daily. “That number is likely to increase with many states moving toward marijuana legalization, so it’s imperative we know what effects prenatal marijuana use may have on infants.”

Elden found that infants who had been exposed to both tobacco and marijuana were smaller in length, weight and head size.

In fact, babies exposed to marijuana were also more likely to be smaller when compared to babies only exposed to tobacco products. This was especially true of babies who were exposed during the third trimester and was more pronounced in boys versus girls.

Babies exposed to marijuana were also more likely to be born earlier than babies who were not exposed to anything.

“We also found that lower birth weight and size predicted a baby’s behavior in later infancy,” Eiden said in an interview with Science Daily. “Babies who were smaller were reported by their mothers to be more irritable, more easily frustrated and had greater difficulty calming themselves when frustrated. Thus, there was an indirect association between co-exposure to tobacco and marijuana and infant behavior via poor growth at delivery.”

Additionally, women who were more stressed throughout pregnancy – showing signs of anger, hostility and aggression – were more likely to continue to use marijuana and tobacco for the duration. The babies’ irritability and frustration are also linked to mother’s who reported higher levels of stress.

“Our results suggest that interventions with women who smoke cigarettes or use marijuana while pregnant should also focus on reducing stress and helping them cope with negative emotions,” Eiden said in an interview with Science Daily. “This may help reduce prenatal substance exposure and subsequent behavior problems in infants.”

You can find the abstract and read more about the study here. For more news from The Everyday Mom Life, click here.

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  • Angela May 21, 2018 03.34 pm

    Thanks for sharing! I was wondering if any studies had been done since this is such a hot topic right now!

  • Ashley @ Wishes & Dishes May 21, 2018 04.50 pm

    This is so scary to read! I’m pregnant right now and it’s so sad to think about babies being negatively affected like that.

  • Brandi May 21, 2018 05.21 pm

    I read this study when I was pregnant. I would get so mad when people would post on the what to expect Message boards that they were smoking weed while pregnant.

  • Stacie May 21, 2018 05.52 pm

    OMG, why would anyone need a study to know that you shouldn’t put anything into your body when you’re pregnant?! I mean, I gave up caffeine when I was pregnant! Smoking pot? Come on. That’s just stupid.

  • Heather May 21, 2018 08.33 pm

    I gave up caffeine for my entire pregnancy. I wouldn’t even take Tylenol until the third trimester. So this kind of stuff always surprises me.

  • Mimi May 21, 2018 10.45 pm

    I’m so against smoking, if it’s forbidden in so many places there must be a reason right?

  • Marysa May 21, 2018 11.03 pm

    Not surprising that there are adverse side effects. It’s good to have these statistics for people to see and do things to care for themselves and their baby during pregnancy.

  • Bonnie G May 21, 2018 11.21 pm

    Thanks for sharing this study. Now that marijuana is legal in some states I wondered about this.

  • Wendy Lemeric May 22, 2018 12.07 am

    I can’t wrap my head around the thought of smoking weed during pregnancy. I don’t understand why some pregnant women need to smoke pot.

  • Trina May 22, 2018 01.03 am

    This makes me so sad, why would a mom put their baby at risk like this. I remember being worried about the wine I drank a week before we found out I was pregnant, I can’t imagine putting my baby at risk throughout my pregnancy!

  • Stephanie May 22, 2018 02.37 am

    My mom has been a special education teacher for many years. I have seen first-hand what fetal-alcohol syndrome does to a child. I can’t imagine putting your child through that when they have no choice in the matter.

  • Marjie Mare May 22, 2018 03.09 am

    I do believe anything we ingest can affect our babies. I was so scared to even drink coffee while pregnant.

  • KAPILA RATTAN BHOWMIK May 22, 2018 03.18 am

    This is a sad thing. I think when a woman gets pregnant she is responsible for another life. Smoking/drugs/alcohol is something i did not even look at during my pregnancy

  • Joely Smith May 22, 2018 03.34 am

    No one should smoke anything while pregnant. I am all for the medicinal ways marijuana can help people but while pregnant everyone needs to be clean as can be. We use enough harsh chemicals in our homes to clean not to mention the stuff put into our food.

  • Stephanie May 22, 2018 03.38 am

    Very interesting. Thanks for shedding light on this subject. It kills me when I see a pregnant woman smoking with all the info we know nowadays.

  • Lois Alter Mark May 22, 2018 04.29 am

    Though pregnant folks have so much information coming their way throughout the process, it’s always so important to be on top of the newest research. Thanks for putting this study out there- I’m sure it will be helpful to many.

  • Melanie May 22, 2018 10.24 am

    While pregnant it is best not to drink alcohol at all. And deffo not to smoke anything x

  • Ruth I. May 22, 2018 12.09 pm

    Smoking is bad for health, what more if a smoker is pregnant? Ugh. I really hope women are considerate enough when they know they have a baby inside.

  • Amy h May 22, 2018 12.57 pm

    I’m a non smoker, and both of my kids full term were only 6lbs.. I could only imagine being a smoker, them being smaller. This is a great study. Thank you for sharign

  • Trang Nguyen May 22, 2018 01.29 pm

    Thank for posting the study. Although I’m not a mom yet but this helps me a lot with knowledge about tobacco and marijuana. How bad are the impacts of them on innocent children!

  • Esther Irish May 22, 2018 02.13 pm

    I’ve never smoked or even thought about it! I was sold on the evils of it from a young age, but education is so important. People need to know the truth.

  • Kara | Dollar Mommy Club May 22, 2018 03.04 pm

    Thanks for sharing. It is important to educate people! This is a very hot topic since mothers who do smoke say it is because it helps with their morning sickness but are forgetting the effect is it having on their unborn child.

  • Becca Wilson May 22, 2018 04.39 pm

    This is such an important study. Lots of people think that marijuana has no real affect.

  • Leah May 22, 2018 05.19 pm

    I honestly get so upset and judgemental when I find out that people are smoking and drinking during pregnancy. In my opinion, wait the 9 months and then resume whatever you were doing.

  • Jess May 22, 2018 07.56 pm

    That’s not surprising to me. I don’t know why someone would even smoke anything while pregnant.

  • Holly Lasha May 22, 2018 07.57 pm

    Thank you for sharing this information. It’s so important that people really understand this issue.

  • Eloise May 22, 2018 08.40 pm

    inhaling anything smoke related into your lungs has an effect on a fetus/baby… I find it kind of shocking and selfish for mothers to smoke, do drugs, and drink alcohol while pregnant… And there after for both parents to expose their babies/kids to 2nd hand smoke, esp since it affects their young ones health (not just the parents!)

  • Angela Tolsma May 23, 2018 01.08 pm

    Fascinating read. I wish there were more studies on marijuana usage and would love comparison studies on achohol vs marijuana during pregnancy.

  • Marcela May 23, 2018 08.38 pm

    This is very interesting study. I’d never guess that. I love to read studies like these. I don’t smoke anything it is good to be aware.

  • Em May 23, 2018 11.44 pm

    I knew it! Smoking is never good for the body. How much more if you are pregnant? But the fact that it’s legal makes anyone think that it’s good. Coz if it’s bad, why would it be legalized in the first place? Thanks for laying out this information in the open.

  • Tara H May 24, 2018 11.54 am

    It is hard to think anyone would encourage smoking of any kind during pregnancy. Even daily medications can be detrimental! Hopefully this will open someone’s eyes


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