Baby on back (Photo credit: Elnaz6 (Own work) [CC-BY-SA-3.0], via Wikimedia Commons)
Elnaz6 (Own work) |Wikimedia Commons | CC BY-SA 3.0

New research from the International Childhood Cancer Cohort Consortium (I4C) confirms that childhood cancer is linked to birth weight. The incidence of childhood cancer appears to be slowly rising, at a rate of approximately 1% per year in developed countries.


Link between birth weight and cancer

The I4C is an alliance of several large-scale prospective cohort studies of children that pools data and biospecimens from individual cohorts to study various modifiable and genetic factors in relation to cancer risk. It found that the occurrence of childhood cancer rises as birth weight increases.

The study observed that risk rose by 26% for every kilogram increase in birth weight for all cancers. In younger children, the risk for leukemia appears to be higher than for all cancers combined, but in children diagnosed at or after three years of age, cancers other than leukemia are more strongly related to high birth weight.


It’s not the mother’s weight gain

Pregnant womanThe research also found that the risk associated with birth weight is unlikely to be primarily due to the mother’s weight gain during pregnancy, one of the contributors to birth weight.

We have been able to compile a significant amount of evidence that effectively shows that childhood cancer incidence rises with increasing birth weight,” said Professor Terry Dwyer, the Executive Director for The George Institute for Global Health. “While we observed a correlation between increased birth weight and higher risk of cancer incidence in children, there were no significant interactions with maternal pre-pregnancy overweight or pregnancy weight gain.

Dwyer, a Professor of Epidemiology at the Oxford Martin School and the Nuffield Dept. of Population Health, leads the I4C, one of the largest initiatives in understanding the role of early-life exposures in childhood cancers. The current knowledge of cancer risk factors to date is mainly based on adult research studies.

Prior to joining The George Institute, Dwyer was previously at the International Agency for Research on Cancer (IARC)—a WHO division—in France. Earlier in his career, Dwyer led groundbreaking research into Sudden Infant Death Syndrome (SIDS) where he contributed important evidence confirming that sleeping position was a major cause of Sudden Infant Death Syndrome (SIDS), leading led to a vast reduction in SIDS deaths around the world.


The power of the collaboration

The relationship between childhood cancers and high birth weights have been posited in previous studies, but the collaboration of I4C allows the simultaneous examination of a wider range of potential factors including maternal age, marital status, education level, smoking propensity, previous live births, diabetes, pre-pregnancy BMI and total pregnancy weight gain.

Globally, there exists a difference in average birth weights across different countries. For example, birth weight in Northern Europe is higher than Southern Europe; and there is a higher incidence of leukemia, the most common childhood cancer, in Northern Europe.


What’s next?

Professor Terry Dwyer, Executive Director, The George lnstitute for Global Health, University of Oxford
Professor Terry Dwyer, Executive Director, The George lnstitute for Global Health, University of Oxford

I4C researchers plan to follow this study up with several lines of inquiry, including:

  • Looking at data in new cohorts such as in Japan and China to see whether this association exists there as well
  • Investigating other factors that have some relationship to birth weight, such as birth order, to see whether the association is similar in infants of different birth order, and
  • Making cord blood measurements from infants in the cohorts to determine whether growth hormones of various types explain what we have found.


Professor Dwyer concludes:

“At The George Institute, we are focused on the prevention and treatment of non-communicable diseases, like cancer. I am more optimistic that we’ll find ways of preventing childhood cancer than I was when we started this study 10 years ago. We know that there are no easy answers, but we are assembling more clues, like this piece of evidence, which will help us fill in the puzzle. Additional research into childhood cancer is needed so that we can provide actionable solutions to improve outcomes for future generations.”

This post was sponsored by George Clinical.


  1. I understand responses to this issue from both sides of the fence. I’m grateful for all research, even if it’s in it’s infancy. Without research into breast cancer, I wouldn’t be here to post this comment. When I first began seeing a blitz of articles about the involvement of genetics, I was annoyed with what I perceived as a blatant scare tactic. My reaction was normal. Denial comes in many disguises. Mine was fear that was causing the denial. No one wants to hear that they, or anyone they love are possible candidates for a disease. I know I didn’t want to hear it! I didn’t want to read about it or even think about it! The Braca Gene was just another one of those half truths researchers come up with or so I thought. Actually, I didn’t think, I just buried my head in the sands of more denial. In short, after waiting too long, I ended up with cancer in both breasts and found out that I did have the Braca Gene. My reconstruction is great. Silicone and a good surgeon made me into a Barbie. However, no matter how nice/real my body looks, it’s not the same as the real thing. Had I paid more attention to research and catered less to my fear, I wouldn’t have gone through a lot of what I had to deal with on my road to recovery. I’ve been in remission for a long time now, but I’m not in denial. I was completely cured of that.
    I realize that this has nothing to do with a baby’s birth weight and cancer. At least not as a direct correlation of circumstances. It does, however, shed a strong light on the value of an open mind when it comes to research. I can readily see why a mother would want to poke holes in this high birthweight/ cancer research information. I would have done the same thing at one time, but not now. Be grateful that there is money for research in this area. You can elect to deny it, believe it or just keep watching to see where it’s going. Don’t look for the exceptions to comfort yourself. They say no pain, no gain and that doesn’t just go for exercising your body. Accepting a possibility, no matter how remote you think it might be is exercising your open mindedness and desire to learn.

  2. Research done by reputable researchers have value beyond measure, BUT…..I believe and agree with alot of the posts here! I am 62, and most babies born around the same time as myself and my older brothers were over 8 lbs. And childhood cancer was almost unheard of. My personal opinion is the medical community keeps blaming something new almost every few months for the cause of cancers. And rarely just say we have way too many chemicals in our lives. In our everyday lives all of us are exposed to billions + of chemicals, we breath them, eat, wear, live in, on, and work with, or around in everything, and place. Even when we think we are in clean air in the country, woods, oceans, there is no place we can be where these killer chemicals are not. Even organic is not organic plants breath, and drink and live in dirt, which is rained on, watered,….so my vote is that living on this planet exposes everyone to carcinagens! Sorry, just don’t think we can point the finger at any one thing. Also a large no. of medications can cause cancer. It’s a crap shoot!!!

  3. I am just getting over cancer. I am the youngest of 3 children. My doctor told me the reason I got cancer was because of the agent orange my father got when he was in the military. When I asked the military for help they told me that if my mother had gotten the agent Orange they would help me. I guess they don’t believe cancer is genetic either.

  4. Patricia you are correct about the research factor. Many moms here should also realize without “research” and medical sutudies many moms would be dying at the operating table by giving birth specifically to these large beautiful babies. Almost lost my wife who is 5.3 giving birth to our 10lbs healthy babies. The second one was actually about a full week to ten days early and that one doctors were saying had more time to develop and quite possibly would have made it to 11lbs workout an issue.

    I also agree with the scare factor stuff because in this case the study seems to be quite premature in its findings. It takes decades to know for certain so many wide range of factors come into play. Humans are probably the most complicated species on this earth and it’s because we are so different due to genetics. We are one of the only species that have same features but look entirely different in some way or another. Millions and millions of us and we are different looking in some way.

    IF… there are aliens out there up in the vast universe there is a darn good reason why we have a general theory why they all look the same it’s called cloning, and they do that to eliminate horrible diseases, and the other is different of opinions because in many cases that’s what leads to hate and destruction. If we are all the same then we are all in the same page but we lose one big factor PERSONALITY.

  5. They will NEVER know what causes cancer but they will keep finding things to blame it on. I’ve always disagreed with his SID position as well. Of all my family members who passed of cancer, not a single one was a big baby or toddler or child or adult. Pretty scrawny actually. Researchers, doctors, politicians, media only tell you what they want you to hear.

  6. Click on their links to the studies and read carefully.
    This article is nothing but the stretching of any tiny grain of anything said in those links. This is not factual. It is a blog.
    Blogs exist to make money.
    The end.
    If you want actual medical data and facts then search for the real studies. Go to the JAMA site or another reputable medical website.
    Anything read on a blog should be read with a wheel barrow full of salt.
    Why are we still so naive?

  7. I agree with Patricia . Research is about ways and means of addressing challenges. The findings apply to the Majority , but there are exceptions .

  8. I kind of get where Jaime is coming from. The statistic of 26% is pretty high but at no time do they say what a “high birth weight” is.
    Are they talking about 9lb babies or 14lb babies? Or does this statistic think that 7lbs is a high birth weight?
    Northern European babies are bigger than Southern European babies but how much bigger? And is this whole study only done in Europe?
    My daughter was 3lbs at birth so do I still have to worry about childhood cancers or am I in the clear?
    Something about the tone of this article doesn’t sit right.
    It leaves me with more questions than answers.


  9. I agree Jamie. I also had all big babies, some 9 pounders too. I weigh 117lb. And I was a big baby too. It’s just genetics.
    Research doesn’t mean much, don’t worry:)
    Just trust in The One Above.

    • Research doesn’t mean much???? If it wasn’t for research we would all still be dying around age 30. Sorry, Elizabeth, you are way off base. By the way, what we know about genetics comes from research. You can trust The One Above, but don’t discount the power of well done research…it may save your life.

  10. I have had three, nine-pound, healthy
    babies. I weigh 116, and was also nine
    pounds at birth. Parents have enough
    to worry about raising their children.
    Shame on you for instilling even
    more worries!

    • Way to take it personally, Jamie…. This article isn’t shaming anyone, it’s merely pointing out that there is a statistical association between birth weight and cancer.


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.