Obesity of pregnant mothers increases the risk of bowel cancer in their adult children

A study published online in the journal Gut shows that obese expectant mothers may increase the risk of bowel cancer in their adult children

The researchers said the findings indicate that conditions in the uterus may be a key risk factor for the disease, which helps explain the rising incidence of this disease among young people

In many high-income countries, the number of new cases and deaths from bowel cancer in the elderly has fallen or remained flat, but the proportion of young people has almost doubled, while the proportion of all age groups in low-income and middle-income countries has remained unchanged.

Therefore, it is estimated that by 2030, the global burden of bowel cancer will increase by 60%, the number of newly diagnosed patients will exceed 2.

Fetal planning is considered to be a factor that affects a variety of health conditions in the course of life, including cardiovascular disease and diabetes

To explore it further, researchers used more than 18,000 mothers and children to study children's health and development (coronary heart disease) at the School of Public Health in Oakland, California, whether maternal obesity, pregnancy weight gain, and high birth weight may be the risk of bowel cancer Improve adulthood

At the time of enrollment (1959-66), mothers provided background information, and at the same time collected details of prenatal examinations, diagnosis and prescription medications from the first 6 months of pregnancy to delivery from their medical records

The mother's body weight (BMI) is divided into: underweight (below 18.

Weight gain is recorded as the rate of weight gain during the first trimester, or the rate of weight gain per week during pregnancy (including 32 weeks); total body weight gain, or the difference between the last weight before delivery and the weight recorded during the first prenatal visit

If the birth weight is 2000 grams or less, it is classified as low weight; the average is 2000-3999 grams; even higher than that

Through contact with the California Cancer Registry, these offspring were monitored for 60 years from birth to 2019

Of the 18751 children, most (48%) were born in the early 1960s

During the monitoring period, 68 people were diagnosed with bowel cancer between 1986 and 2017, aged between 18 and 56 years

The offspring of obese (16%) mothers weighed 4000 grams or more at birth, which is higher than the proportion of underweight/healthy (7.

Compared with underweight or healthy weight, overweight and obese offspring have more than double the risk of bowel cancer

Although early weight gain is not associated with the risk of bowel cancer, overall weight gain is associated with the risk of bowel cancer, and the risk of weight gain of 23-29 pounds has doubled

Compared with people whose birth weight was within a healthy range, those with a birth weight of 4000 grams or more are also at higher risk of disease
.

This is an observational study, so the cause cannot be determined
.
Factors common to mother and child, such as diet and microbiota, may affect the outcome, and these factors are not captured in coronary heart disease
.
Similarly, the weight of offspring is not measured throughout adulthood
.

But the researchers said that the results of the study indicate that “the good relationship established between obesity and colorectal cancer may have originated in the period before birth
.
”

They explained that the nutrients received in the uterus may permanently change the structure and function of adipose tissue, appetite regulation and metabolism, and excessive exposure to insulin and growth hormone may affect insulin sensitivity
.

"Our findings provide convincing evidence that an important risk factor for in-utero events (colorectal cancer) may lead to increased incidence in young adults," they wrote, adding: "Maybe also There are other unknown risk exposures that produce this disease during pregnancy and early life, which are worthy of further study
.
"

They concluded: "Considering the population trend of maternal obesity, the prevalence of obesity has increased by nearly six times since the 1960s, and we may see an increasing burden of early onset (intestinal cancer) in the next few decades.
The heavier
.
"

DOI 10.
1136 / gutjnl-2021-325001

Maternal obesity, pregnancy weight gain, and birth weight and risk of colorectal cancer