Post-50 pregnancies are riskier than from 45-49 [pg. 6]

By JUDY SIEGEL-ITZKOVICH
It might seem obvious that having a baby after the age of 50 can be riskier for mother and baby than it is between 40 and 49. But a new study at Sheba Medical Center - published in the November issue of Obstetrics & Gynecology, produced some surprising conclusions. As more women are giving birth after 50, thanks to infertility treatments, this is a subject of growing interest. Prof. Michal Simchen and colleagues examined the records of 123 women aged 45 and over who gave birth at the Tel Hashomer hospital between January 1999 and June 2004. Twenty-four of them were between 50 and 64 at delivery, and all conceived via in-vitro fertilization using donor eggs. Some, but not all, of the 99 women in their 40s underwent IVF and used donor ova. Pregnancy in one's sixth decade is more dangerous than giving birth even a few years earlier, the researchers found. Complications were more common than in women who delivered in their mid- to late 40s. The older women had to be hospitalized during pregnancy almost three times as often as those under 49 (63% compared with 22% of those aged 45 to 49), and twice as many had low-birth-weight babies (61% compared with 32%). The average pregnancy involving single babies born to the older mothers was 36.9 weeks, compared with 38.4 weeks among the women in their 40s. However, the authors wrote that "it was encouraging to see that the pregnancy outcome... was generally good." No severe birth defects related to premature delivery occurred among the babies born to the older women, even though the premature birth rate was high. The prevalence of pregnancy-related diabetes and high blood pressure was high overall - 21% and 28% respectively - but these complications were equally common in both age groups. The bottom line of the study is that women in their 50s who want to get pregnant should be well aware of the fact that they and their infants face increased risks. But this does not rule out the possibility of being a mother at an age when other women are already grandmothers. HOW TO BRING DOWN BLOOD PRESSURE Want to know a pleasant way to lower your blood pressure by 10 points? Exercise! Physical activity can reduce the need for anti-hypertension drugs, and also prevent the onset of high blood pressure. A special four-page section in the September issue of the Harvard Heart Letter also advises taking your blood pressure regularly at home. A diet rich in vegetables, fruit, low-fat dairy products, whole grains, poultry, fish and nuts can also lower weight and blood pressure. Smoking a cigarette can cause a 20-point spike in systolic pressure, and having more than one alcoholic drink a day can also contribute to higher pressure, says the newsletter. Too much salt and too little potassium can also boost pressure. Meanwhile, Indiana University researchers found that three or four short, brisk walks throughout the day can be more helpful to people watching their blood pressure than one continuous bout of exercise. "The biggest problem for most people is they don't have the time," says kinesiology Prof. Janet Wallace, who writes in a recent issue of the Journal of Hypertension. "You might think, 'I don't have the time to go to the gym or work out for 40 minutes, but I might have the time to do 10 minutes here, 10 minutes here and another 10 minutes here.' Four 10-minute walks would be ideal." Her study compared the effect of accumulated versus continuous physical activity on prehypertension - an elevated blood pressure level that typically progresses to high blood pressure. She found that both forms of exercise, accumulated and continuous, decreased study participants' blood pressure by the same amount. The effect lasted for around 11 hours in the group that took four 10-minute walks, compared to seven hours for the group that walked continuously for 40 minutes. "We had no idea the short bouts would be better," Wallace said. "Most studies in the literature report the long, continuous session are more effective for many variables." TAKE IT SLOWLY When your mother told you that if you chew slowly you won't be so hungry, she was right. There had been no scientific evidence to support the theory, but now a laboratory study has confirmed the long-held belief. "It started in about 1972 as a hypothesis that eating slowly would allow the body time for the development of satiety, so we would eat less," said Prof. Kathleen Melanson, an expert in nutrition and food science at the University of Rhode Island. "Since then we've heard it everywhere, and it has become common knowledge. But no studies had been conducted to prove it." In fact, early evidence suggested the opposite to be true: In the 1990s, one study examined the role of small bites and found no effect, while a study of pauses between bites actually showed increased food consumption. But a lab study of college-aged women over the past year led by Melanson confirmed the notion. The results were reported in October at the annual meeting of the North American Association for the Study of Obesity. In the study, 30 women made two visits to Melanson's lab, and each time were given a large plate of pasta and told to eat as much as they wanted. When they were told to eat quickly, they consumed 646 calories in nine minutes, but when they were encouraged to pause between bites and chew each mouthful 15 to 20 times, they ate just 579 calories in 29 minutes. "Satiety signals clearly need time to develop," Melanson concluded. "Not only did the women take in fewer calories when they ate more slowly, but they had a greater feeling of satiety at meal completion and 60 minutes afterwards." The women also said they enjoyed the meal more when they ate slowly, Melanson added. One potentially confounding factor was that the volunteers were provided water with their meal, and when eating slowly had considerably more time to drink, and the greater consumption of water might have contributed to satiety. However, Melanson said this factor reflects the real-world situation, since eating slowly allows more time for water consumption. She will conduct follow-up studies next spring that factor in water consumption as well as the drinking of higher-calorie beverages such as soft drinks or juices. Melanson also plans to study "the physiological signals that suppress hunger or enhance satiety to see if there is a mechanistic explanation for our results."