Thursday, October 9, 2008

Putting the Baby on a Diet Before It's Even Born

Two of the most important questions in the "fat women should gain less weight in pregnancy" movement are:
  1. Exactly what means should be used to achieve that smaller weight gain (i.e. do they recommend hypocaloric diets to obese women in pregnancy)

  2. What will providers do to enforce a particular weight gain if a fat woman starts to gain more than allowed despite normal nutrition
The answers to these questions are very important.

Normal Eating vs. Hypocaloric Diets

When advising their obese patients to aim for a smaller weight gain in pregnancy, some care providers simply mean "Eat healthy and normally, exercise regularly, and if you don't gain much weight, that's fine."

There's nothing wrong with this approach. As we have established, many larger women don't gain as much weight in pregnancy regardless of what they eat. It's not outside the range of normal. As long as they are eating healthfully and not restricting calories, whatever they gain (or don't gain) is fine.

[Of course, part of the problem with some doctors is their assumption that fat women OBVIOUSLY eat poorly so therefore eating healthy must represent a major change in intake and lifestyle and so they won't gain much weight at all. I can't tell you how much those assumptions irritate me. But I digress.]

But when some doctors advise gaining less weight in pregnancy, they mean manipulating their clients' food intake in order to achieve a lower weight gain. They're not just talking about eating healthfully and normally, they basically mean prescribing hypocaloric diets in pregnancy.

And if their clients start to gain more than what is "allowed," some doctors use scorched-earth techniques to limit that gain.

This is why the movement to limit weight gain in pregnant obese women is most alarming. This is the course of action that is dangerous and must be questioned.

What Is Normal Caloric Intake in Pregnancy?

Of course, a discussion of all this depends on what you think is a normal caloric intake in pregnancy.

Most sources just say it's 200-300 calories beyond your normal intake in the 2nd and 3rd trimester. Many don't specify a total number, but simply note that 200-300 calories extra is all you need and that doesn't take much extra food.

The sources that specify caloric intake say slightly different things:

  • The National Institute of Diabetes and Digestive and Kidney Diseases says that normal pregnancy caloric intake can vary from 1900-2500 calories, depending on your activity level, height, and energy needs
  • The RDA/DRI for pregnancy is usually cited as 2400-2500 calories in books

  • The American Dietetic Association says that most pregnant women need 2200-2900 calories during pregnancy
So even "official" sources differ somewhat in the total calories needed during pregnancy but let's assume around 2400 calories; a bit less if you are not very active.

Calorie Intake for Obese Pregnant Women

But if women of average size are "supposed" to eat somewhere around 2400 calories, give or take a bit, how many are fat women supposed to have?

Well, few sources will tie themselves to recommending that fat women only eat "x" calories in pregnancy....most just strongly imply that fat women should be eating far less than the norm.

What happens most often is that doctors and pregnancy books tell women they should NOT gain much weight in pregnancy.....and then they leave it up to the mother to deduce how to achieve such a limited gain.

So even if a care provider doesn't directly say, "Eat only xxxx calories," the advice to strongly limit weight gain indirectly is going to lead to hypocaloric intakes in many women.

Some sources are not afraid to come right out and recommend caloric restriction to women of size. For example, fat women with diabetes or gestational diabetes are routinely advised to restrict their calories because borderline starvation has been shown to lower blood sugar. So there are some studies that show that women have slightly lower blood sugar if they are given hypocaloric diets.....but is this really harmless to the baby?

The degree to which obese pregnant women with diabetes or GD should be restricted is controversial. Many programs limit obese women to somewhere around 1400-1600 calories. Some have limited women to as few as 1000-1200 calories.

Non-obese pregnant women with diabetes/GD, on the other hand, usually are given at least 2000 calories and often more like 2400-2500.

Please note---that's 500 - 1000 calores less per day!

My question is....why would it take fat pregnant women less calories to grow a baby than average-sized women? Isn't the actual caloric/energy cost of growing a healthy baby going to be similar among women of all sizes?

Sure, obese women have fat stores already and so we don't need extra calories for building up fat stores. So I could buy a few less calories per day.....but 500-1000 less calories per day?

That is a lot more than the difference between a bit of extra fat stores or not. With that kind of restriction it's difficult to believe the mother is getting all of what she optimally needs nutritionally.

But it's not just GD mothers that are getting hypocaloric advice. Although such drastic cuts are by no means universally advised, it's still not uncommon for women of size to be given hypocaloric diets in pregnancy.

Here's a website....from a registered dietician no less!.....that recommends that obese women select her 1500-1700 calorie plan, while overweight women get to whoop it up on her 1800-2000 calorie plan. Whooohooo.

And it really isn't all that uncommon for obese women to be told to limit her calorie intake to somewhere in the 1500-1800 calorie range.

Real-Life Dietary Advice

But is this kind of restriction just the result of a few raving lunatics here and there, or is this kind of advice really common?

Here is a sampling of just a few of the emails I've seen over the years, documenting reduced caloric diet advice during pregnancy:

  • When I was pregnant with my first, [the doctor] had me on a 1800 calorie diet
  • My [relative] will be having her baby [soon]. They just tested her a few weeks ago and she says her sugar is "borderline." They put her on a 1500 calorie diet.
  • [At 22 weeks pregnant], the OB told me I probably had gestational diabetes. [He] suggested I go on a 1500 calorie diabetic diet.
  • While [pregnant] with *twins*, the nutritionist put me on an *1800* calorie diet
  • At our first meeting the nutritionist very patronizingly recommended we all eat as much aspartame as possible before introducing us to our new diet, one that I would later calculate to add up to roughly 1300 calories per day.
  • My fat-phobic OB...put me on an 1000-1100 calorie a day diet with baby #4

Although 1500 and 1800 calorie diets in pregnancy are most common, I have read studies (yes, recent ones!) where they had PREGNANT fat women on 1200 calorie diets! It's not common but unbelievably, it does still happen.

WHAT are they thinking?

The Scorched-Earth Approach

And the further question is, if women gain more weight than their doctor tells them they may gain....what then?

[Note: Some of these stories have been mentioned before, but they bear repeating in this context.]

Is she going to be harassed every time she gets weighed at the doctor's?

  • Although my OB is a decent man, he constantly hammers me about my weight (I've lost 3 lbs. during this pregnancy so far), and I am scared to death to step on the scales at my appointments

Is she going to be sent to Weight Watchers or Jenny Craig in an effort to keep her weight gain down?

  • [The nurse-midwives at the birth center] sent me to Weight Watchers and told me not to gain weight or they wouldn't be able to keep me.
  • After meeting with the OB nurse, she said that I could go back to WW.
  • I am 9 weeks pregnant and [my midwife] said I need to go on a diet. She said I can go back to Jenny Craig, like I was doing before I was pregnant.

Is she told to diet during the last trimester of pregnancy when the baby is really developing neurologically?

  • I was told not to gain any more weight when I reached about 7½ months with my first 2 pregnancies. So I’d try to starve (and not succeed) during the 8th & 9th month when my little guys were trying to grow their brains
  • I have gained 18 pounds so far..[the doctor] had a fit. She told me...I had better lose weight. I asked, "Do you mean not gain any more?" and she said, "NO, you need to LOSE weight.”
  • [The doctor] said I mustn't gain more than 20 lbs., 15 was even better, because I was overweight. If I gained more, he'd put me on a diet...I left the doctor when I was 5 months pregnant. [My] cousin stayed, and obeyed. When she reached her weight limit he [did] put her on a diet.

Is she going to be told to go to extremes in order to limit weight gain?

  • [The OB told me, while pregnant with twins, to drink Slim-Fast in order to keep down my weight gain.]

This is one of the most critical questions. What interventions are going to be used to curtail or prevent an "excessive" weight gain? And how can we be sure they are not doing more harm than good?


Let's be fair. Most doctors these days do not advise fat women to diet during pregnancy, but there is a movement afoot return to this, and some doctors (and even some midwives) are advising reduced caloric diets.

Furthermore, the common advice for obese women to gain minimally during pregnancy means that many of them will adopt reduced calorie diets during pregnancy in order to achieve that goal.

And if the Institute of Medicine (IOM) revises its weight gain guidelines (as they are currently considering doing), many doctors (and even midwives) will see this as a justification to put more and more obese women on reduced calorie diets.

And this sort of thing has the potential for far-reaching consequences.

You know that the obesity hysteridemic in this country is way out of control when they are, in effect, promoting putting the baby on a diet before it's even born.

Next: The potential effects of fetal undernutrition

Monday, October 6, 2008

A Little Historical Perspective on Weight Gain in Pregnancy

Preventing Pre-Eclampsia and Big Babies

Years ago, doctors regularly advised women to strictly limit their weight gain in pregnancy. They viewed this as a way to prevent pre-eclampsia (high blood pressure issues in pregnancy) because one of the symptoms of pre-eclampsia is a high weight gain from retaining fluids.

They decided that the large weight gain must be causing the pre-eclampsia, and therefore, preventing a large weight gain would help prevent pre-eclampsia.

They also wanted to prevent women from having large babies, so they strongly counseled women of all sizes to limit weight gain in order to get a smaller baby.

[Not only did they restrict weight gain, they also advised women to smoke to keep down their weight gain and fetal size, or to use diuretics to prevent fluid retention, both of which were later discovered to cause serious problems in pregnancy. Doh!]

All this was in the name of a worthy goal----preventing pre-eclampsia, which can be a very serious complication of pregnancy, and which is potentially deadly to both mother and baby. Their hearts were in the right place, but their methods were ill-considered and extreme.

Furthermore, the safety of this approach had not been established before it was adopted, as is unfortunately common in obstetrics. (Think of all the babies damaged when their mothers' doctors prescribed DES.)

Unforseen Consequences: Underweight Babies

What they found out later was that these extreme approaches actually CAUSED more harm then they averted. Many babies were born too small or very stressed; some no doubt died as a result of these interventions.

We also know that babies born underweight or "small-for-gestational age" (SGA) have more health problems later in life so the consequences of restricted fetal growth go far beyond problems at birth.

This is why the Institue of Medicine (IOM) adopted new weight gain guidelines in 1990, raising the recommended weight gains in pregnancy. They noted years of research that showed that low weight-gain in pregnancy caused an increase in SGA women of all sizes.

They also noted that in the 70s, when weight gain restrictions began easing up, there was a strong reduction in the occurrence of SGA babies.

So they raised the guidelines, and then began the big job of trying to get doctors to believe in this new system of weight gain guidelines. It was a difficult job.

Current IOM Weight Gain Guidelines

The old weight gain recommendations vary by source and by decade to some extent, but generally they fell somewhere between 10-20 lbs. By the 1970s, several organizations set a desirable range of around 20-25 lbs. or so.

The IOM raised these guidelines...but not across the board. They differentiated weight gain recommendations by BMI. Their guidelines were:

  • "Underweight" women: 28 - 40 lb. weight gain
  • "Normal" Weight women: 25 - 35 lb. weight gain
  • "Overweight" women: 15 - 25 lb. weight gain
  • "Obese" women: at least 15 lb. weight gain

The reason they had different weight goals by BMI was because weight gain's effect on fetal size varies by pre-pregnancy BMI.

The highest risk for SGA babies was in underweight women who didn't gain enough weight in pregnancy. Research clearly shows that gaining more weight can prevent many SGA babies in this group, so they raised the upper limit in this group to 40 lbs.

The effect of greater weight gain in preventing SGA babies is less pronounced as maternal size goes up; thus they felt that smaller gains were justifiable in the other groups. Still, women of "normal" size were now allowed to gain up to 35 lbs., which was a little more lenient than in the past.

The effect of weight gain on SGA babies is least strong in overweight and obese women, so therefore they felt only a small weight gain was appropriate in this group.

However, they did note that very small weight gains/losses caused increases in SGA babies across the board, even in obese women, and therefore they were not comfortable in recommending <15>This has been very controversial; many doctors still believed that obese women should gain little or nothing in pregnancy. They believed a larger gain in fat women would lead to a stronger risk of....ta da!!....pre-eclampsia. And big babies. And cesareans. And would result in more obesity after the pregnancy because of retained weight. So they've been chafing under these "guidelines" ever since.

Pressure to Revise the Weight Gain Guidelines

This chafing over guidelines has reached fever pitch now as a result of the obesity hysteridemic. More and more are pressing for lower weight gain goals.

Recently, a number of doctors have banded together to pressure the IOM to revise its guidelines on weight gain in pregnancy, and in particular to lower the guidelines for obese women.

They are hawking the same old concept again, namely: Large women have a higher risk for pre-eclampsia and big babies, so if we prevent a large weight gain in them, we'll lower the risk for pre-eclampsia and get smaller babies!! And prevent further obesity afterwards!!

Know what guidelines they are proposing for obese women?

  • Class I obese women (BMI 30-34.9): 10 - 25 lbs. gain
  • Class II obese women (BMI 35-39.9): 0 - 9 lbs. gain
  • Class III obese women (BMI >40): 0 - 9 lbs. loss
That's right, they are proposing that some fat women BE REQUIRED TO LOSE WEIGHT DURING PREGNANCY.

Alas, their P.R. campaign is working; the IOM has begun meetings to discuss revising weight gain guidelines again.

Coming Soon: Deconstructing the research being used to justify lowering these cutoffs.