Excess Weight Gain in Pregnancy Leads to Bigger Babies
Wednesday, November 3, 2010
Readers of these pages are by now quite familiar with the increasing evidence showing that what happens to the fetus in utero may be a key determinant of obesity risk later in life. Thus, both small-for-gestational-age and large-for-gestational-age babies appear at increased risk for becoming obese kids (and adults).
One of the important determinants of infant weight is the magnitude of maternal weight gain in pregnancy. But how strong is this relationship really?
This question was now examined by David Ludwig (Harvard) and Janet Currie (Columbia) in a paper published last month in The Lancet.
The researchers examined data from a population-based cohort study that included all known births in Michigan and New Jersey, USA, between Jan 1, 1989, and Dec 31, 2003, or a total of 513 501 women and their 1,164,750 offspring.
Using a within-subject design to reduce confounding to a minimum, they noted a strong and consistent association between pregnancy weight gain and birthweight: infants of women who gained more than 24 kg during pregnancy were almost 150 g heavier at birth than were infants of women who only gained 8-10 kg.
Women who gained more than 24 kg during pregnancy were more than twice as likely to give birth to an infant weighing more than 4000 g than women who only gained 8-10 kg.
In light of the increasing evidence that larger infants are much more likely to become overweight and obese children (and later adults), this study certainly supports the need for efforts to prevent excessive weight gain during pregnancy.
Targeting obesity prevention and treatment strategies to younger women and limiting excessive weight gain during pregnancy, may well be the single most effective way to prevent obesity in future generations.
AMS
Edmonton, Alberta
Ludwig DS, & Currie J (2010). The association between pregnancy weight gain and birthweight: a within-family comparison. Lancet, 376 (9745), 984-90 PMID: 20691469
Wednesday, November 3, 2010
Interesting article Dr. Sharma. I think it is important to note that Health Canada currently advises that a woman with a “normal” pre-pregancy weight should aim to gain 11.5 to 16 kg (25-35lbs). The Institute of Medicine and also recommend this range.
I agree with the conclusions that 24 kg (~53 lbs) is excessive weight gain and should be avoided to protect the health of both mom and baby. However, I feel that it should be clarified, for those readers that do not have a science or health background, that a woman with a “normal” pre-pregnancy weight should not misinterpret the findings of this study (it is NOT advised to gain only 8-10 kg during her pregnancy; the 8-10 kg was simply the reference range selected for this study).
http://www.hc-sc.gc.ca/fn-an/nutrition/prenatal/qa-gest-gros-qr-eng.php
http://www8.nationalacademies.org/onpinews/newsitem.aspx?RecordID=12584
Thanks,
🙂 Lindsay (7-months pregnant dietitian from SK)
Wednesday, November 3, 2010
I had a relative with a normally slim build who gained 70 – 90 lbs. in each of her three pregnancies despite not overeating. Her habit when not pregnant was to only eat one meal a day as a way of keeping her weight down. When pregnant, however, she adhered to a more nutritious regimen of three meals a day. As we now know, starving yourself for most of the day will result in a depressed metabolism. I have no doubt that her extreme weight gains during her pregnancies, despite eating only a normal amount, was a result of training her body to store calories when not pregnant. By extension, perhaps even eating behaviour pre-pregnancy can therefore effect baby weight.