Large Weight Gain In Pregnancy Tied To Increased Infant Size

Dr. Enrique Jacome MD

Obese mothers who gain excessive weight during pregnancy are nearly seven times more likely to give birth to a large infant at risk for a lifetime of obesity. Moreover, excess gestational weight gain (GWG) increases the risk of having a large infant, even in mothers who have a healthy prepregnancy body mass index (BMI), according to a study published April 17 in the Journal of Maternal-Fetal and Neonatal Medicine.

The study, by Zachary M. Ferraro from the Healthy Active Living and Obesity Research Group, Children's Hospital of Eastern Ontario Research Institute, Ottawa, Canada, and colleagues, showed that overweight and obesity were associated with an increased risk of having a child considered large for gestational age (LGA) — a risk factor in future obesity. The risk of having an LGA infant increased dramatically if an overweight mother gained more weight during pregnancy then recommended by Institute of Medicine (IOM) guidelines.

The researchers analyzed data from 4321 mother-infant pairs recruited from 2002 to 2009 in the Ottawa and Kingston Birth Cohort. Their goal was to determine the effect of maternal weight and weight gain during pregnancy on the likelihood of giving birth to a child weighing more than 4000 g (8.8 pounds), which puts the child in the 90th percentile for infant weight.

Mothers who reported a prepregnancy BMI indicating overweight — 25 to 29.9 kg/m2 — were nearly twice as likely to give birth to an LGA infant (odds ratio [OR], 1.99; 95% confidence interval [CI], 1.17 - 3.37) as women of healthy weight. For obese women, with a BMI of 30 kg/m2 or more, the OR was 2.64 (95% CI, 1.59 - 4.39).

If a mother's GWG exceeded IOM guidelines, the risk of having an LGA infant increased for women of any weight at pregnancy, (OR, 2.86; 95% CI, 2.09 - 3.92), after adjustment for a mother’s prepregnancy BMI, age, smoking, and maternal height. The problem was compounded if a woman was already overweight or obese: ORs were 3.59 for overweight women (95% CI, 2.60 - 4.95) and 6.71 for obese women (95% CI, 4.83 - 9.31).

"Obesity can become part of an intergenerational cycle," Kristi Adamo, MSc, PhD, coauthor of this report, said in a news release from the University of Ottawa. Dr. Adamo is also the cofounder of the Healthy Active Living and Obesity Research Group at Children's Hospital of Eastern Ontario Research Institute.

"Birth weight averages can be an indicator of the weight a child will carry through preschool and even into adulthood. It's critical for a mother to understand that her healthy eating and lifestyle decisions during pregnancy will impact much more than a nine-month gestation period," she continued.

The adjusted analysis also found smoking mothers were less likely than nonsmokers to deliver an LGA infant (OR, 0.53; 95% CI, 0.35 - 0.79). Parity was associated with an increased risk for an LGA infant (OR, 1.49; 95% CI, 1.22 - 1.82).

The range of acceptable weight gain during pregnancy recommended by the IOM changes according to a mother's weight at the time of pregnancy. Women considered underweight, with a BMI less than 18.5 kg/m2, should gain 12.5 to 18 kg (28 to 40 pounds). Healthy-weight women — BMI of 18.5 to 24.9 kg/m2 — should gain 11.5 to 16 kg (25 to 35 pounds). Overweight women are advised to gain 7 to 11.5 kg (15 to 25 pounds), and obese women, 5 to 9 kg (11 to 20 pounds).

In the study, only 29.3% of the women stayed within IOM GWG guidelines. Another 57.7% exceeded the recommendations. Before pregnancy, 23.7% of women in the study were overweight, and another 16.2% were obese.

"We have shown that the majority of women in our birth cohort population entered pregnancy at an unhealthy weight and gained in excess of recommendations during gestation," the authors noted. "At any weight, excessive GWG has a significant effect on the likelihood that their child will be born LGA, and research has demonstrated that size at birth contributes to obesity development down-stream."

www.fleurhealth.com

Women Who Don't Exercise Are At Greater Risk Of Developing Metabolic Syndrome

Dr. Enrique Jacome

A national study shows that women are less likely than men to get at least 30 minutes of exercise per day, resulting in greater odds of developing metabolic syndrome - a risky and increasingly prevalent condition related to obesity.

Metabolic syndrome is a name for a group of risk factors - including high cholesterol, high blood pressure and extra weight around the middle part of the body - which occur together and increase the risk for coronary disease, stroke, and Type 2 diabetes.

The study, now online in the journal Preventive Medicine, was conducted at Oregon State University by Paul Loprinzi and Bradley Cardinal, professor of social psychology of physical activity at OSU. Loprinzi is now an assistant professor of exercise science at Bellarmine University. He conducted the research when he was a student in Cardinal's lab at OSU.

"The results indicate that regular physical activity participation was associated with positive health outcomes for both men and women; however, there was a greater strength of association for women," Loprinzi said.

Looking at more than 1,000 men and women from a nationally represented sample, the researchers found that women were getting only about 18 minutes of moderate-to-vigorous exercise daily, compared to men who, on average, were getting 30 minutes of moderate-to-vigorous exercise daily.

"Those who get at least 30 minutes of exercise a day are less likely to be depressed, less likely to have high cholesterol and less likely to have metabolic syndrome," Loprinzi said.

Loprinzi and Cardinal's study is unique in part because it is the first to use an "objective" measure of physical activity - in this case participants were outfitted with accelerometers that measured daily activity. In their study, slightly more than one in three women had metabolic syndrome, and one in five had symptoms of depression.

"It's pretty striking what happens to you if you don't meet that 30 minutes a day of activity," Cardinal said. "Women in our sample had better health behavior - they were much less likely to smoke for instance, but the lack of activity still puts them at risk."

Cardinal said depression puts people at more risk of abdominal fat and insulin resistance, and both are risk factors for metabolic syndrome.

"Physical activity has been shown to reduce depression," he said. "So the key message here is to get that 30 minutes of exercise every day because it reduces a great deal of risk factors."

While their study does not address why women were not getting enough exercise, the authors said research shows that physical activity patterns often begin in childhood.

"Research has shown that around ages 5 or 6 these patterns begin," Cardinal said. "Parents tend to be more concerned with the safety of girls, and have more restrictive practices around outdoor time and playtime than with boys."

Loprinzi said this pattern tends to continue into adulthood, and that overall confidence may be a factor.

"Some evidence indicates that women, compared to men, have less confidence in their ability to overcome their exercise-related barriers," Loprinzi said, adding that women also often cite a lack of time to exercise due to child-rearing.

The researchers have a study coming out that may help those time-challenged women. Loprinzi said he and Cardinal found that adults can still enhance their health by accumulating physical activity in short periods throughout the day, such as taking the stairs instead of the elevator or pacing while talking on the phone. 

www.fleurhealth.com

The Link Between False-Positive Mammography Results And Breast Cancer Risk

Dr. Enrique Jacome MD

False-positive mammograms could be an indicator of underlying pathology that could result in breast cancer, according to a study published in the Journal of the National Cancer Institute.

Screening mammography is associated with false-positive test results in disease-free women, and those women are usually referred back for routine screening after the initial diagnostic work-up does not reveal cancer. Suspicious findings on screenings leading to false-positives include asymmetric densities, skin thickening or retraction, tumor-like masses, recently retracted nipples or suspicious axillary lymph nodes. It is unknown if women whose mammographic screenings show these results have a higher long-term risk for breast cancer compared to women who initially test negative.

In order to determine if women who test false-positive after mammography screenings have a higher risk of developing breast cancer than those who test negative, My von Euler-Chelpin, Ph.D., in the department of public health at the University of Copenhagen and colleagues, gathered data from a long-standing population-based screening mammography program in Copenhagen, Denmark from 1991-2005. They evaluated the risk of breast cancer and ductal carcinoma in situ in women who had received false-positive test results between the ages of 50-69 . The age-adjusted relative risk of breast cancer for women who had tested false-positive for breast cancer was compared to women who had tested negative.

The researchers found that women who had tested negative for breast cancer had an absolute cancer rate of 339/100,000 person-years at risk, compared to women who tested false-positive, who had an absolute cancer rate of 583/100,000 person-years at risk. The relative risk of breast cancer in women with false-positive tests was statistically significantly higher than women who tested negative even at 6 or more years after the test. However, the researchers caution that "The excess breast cancer risk in women with false-positive tests may be attributable to misclassification of malignancies already present at the baseline assessment," the authors write. Thus, new screening methods such as high-resolution ultrasound and stereotactic biopsy may result in more accurate diagnoses and fewer false positives on first screen.

The authors also caution that the experience of a false-positive may cause anxiety, which may discourage women from attending regular screenings. However, the long-term excess risk of breast cancer in women who tested false-positive underscores the need for women to have regular screenings. "Based on the findings in this study, it may be beneficial to actively encourage women with false-positive tests to continue to attend regular screening."

www.fleurhealth.com