On Complacency....and Pregnancy Weight Gain

No one strives to be complacent. In any sphere of life. But I believe there are so many instances in life where we are lulled into complacency, even encouraged to be complacent. Weight gain during pregnancy is one such situation. Clearly, when normal weight women become pregnant, they need to gain weight. Fetuses and all the support structures they require weigh something. And people who start out thin (or healthy), will need to gain lbs corresponding to these structures. But how much? What should this weight distribution be? How do fit women balance eating with the decrease in exercise intensity that inevitably is a part of a healthy pregnancy?

I am doing many things well during my pregnancy. But there are things I wish I had done differently and changes I plan to employ going forward. When I first became pregnant, I immediately changed my exercise intensity intentionally, but unintentionally also decreased my frequency due to fatigue. The amount of calories I took in probably decreased from baseline (though I wasn't keeping track) and my hunger level definitely decreased which made sense given my decrease in exercise. But I didn't play close attention to what I was eating and aside from keeping up my running mileage enough to complete my marathons, I didn't have specific exercise goals. Looking back, I should have started tracking what and how much I was eating more closely and set some specific non-running goals for myself. And I should have incorporated more weight training (but that's the story of my life, in general, not just during pregnancy!)

My 2nd trimester started off well with another marathon but quickly deteriorated from a physical fitness standpoint as I took a few days off from heavy exertion for my amniocentesis. Then some unanticipated concerns about our baby's health (don't worry, everything ended up okay) made me pretty sad for a few weeks while we were in medical limbo and I just couldn't force myself to stay as active as I should have. And I definitely wasn't paying attention to what I was eating. For the past few weeks, things have been going well. I feel great, babybison is kicking away in there, all is good. And my 45 in 45 goal (45 minutes of exercise for 45 days in a row) has really helped me to stay active. Eating wise, I have tried to not go crazy, but I have definitely been paying a bit less attention than usual to my intake. But my 14 lb weight gain at my last appointment (though I was wearing heavy boots, I like to believe it was only 12!) was shocking. But the number was less disturbing to me than the fact that I feel and look out of shape. I'm happy to gain weight in the fetus and the uterus and the amniotic fluid, but I really don't appreciate weight gain in my legs....or back....or arms. That is not pregnancy weight gain- it's complacency. And I will not continue to be complacent.

So I decided to look into the data. What is the pregnancy weight gain breakdown? How much is actually required? Where do these guidelines come from? And what do I need to do in the last 3 months to ensure the health of both my baby (weight gain) and me (no excess weight gain and the barest minimal of fitness loss).

First, a bit of history.....

Prior to the 1930s, there was a societal belief that excessive maternal weight gain led to obstetrical problems and women were actually advised to not gain more than 15 lbs. In the 1970s a few studies indicated that maternal dietary restriction correlated with low birth weight babies and the weight gain recommendation changed, somewhat arbitrarily, to 20-25 lbs. Note that all of these "studies" including the one I go into detail below are observational studies- it is not ethically possible in the modern age to rigorously study maternal weight gain. A high quality study would be one that randomly assigned some women to the currently recommended weight gain (25-30 lbs for normal weight women) versus less weight gain, and then compared outcomes. Not many women would volunteer for such a study and even if they (and their physicians) were willing, there would be no way to truly control each woman's weight gain, let alone control for all the other factors that go into maternal and fetal health (smoking, drinking, exercise, medical problems, etc).

The current weight gain recommendations come from various bodies such as the Institute of Medicine (IOM). The IOM guidelines were updated in 2009 and, interestingly, the update focused mostly on avoiding excessive weight gain particularly in overweight women.  They discuss how many women go into pregnancy already overweight and how they need to carefully limit weight gain and how women who go into pregnancy with normal weight end up gaining way too much and often don't lose it postpartum (thus remaining overweight or obese for the rest of their lives). They recommend many women spend time losing weight PRIOR to getting pregnant so as to start from a healthy weight. So we've come full circle from asking pregnant women to restrict weight gain in the 1930s to asking them to gain in the 1970s to asking them to carefully gain and even consider pre-pregnancy weight loss.

Here are the official weight gain guidelines from the IOM:

Just to give you a sense, a 5'5" woman who weights 150 lbs has an upper limit of normal BMI of ~25. More than that= overweight. Note that 27% of women of childbearing age are obese, not just overweight, but obese!

For those interested here is one of the more recent, sub-optimal, study the guidelines are based on.
This study followed ~3000 women in Brazil in the 1990s, with results recently reported in January 2013. They followed womens' weight gain in the 2nd and 3rd trimester and compared them to the 2009 IOM recommendations. What they found was interesting:

• Roughly 50% of women had "excessive" weight gain in the 2nd and 3rd trimester
• Women who were obese prior to pregnancy were at higher risk of gaining excess weight.
• Mean weight gain was higher in the 2nd trimester than in the 3rd for non-obese women (good news for me, hopefully the vast majority of my weight gain is behind me!). Obese women just kept gaining.
• "Insufficient" weight gain (defined as below the minimum as recommended by 2009 IOM) was correlated with a lower risk of c-section (statistically significant) and higher risk of pre-term birth (not statistically significant). However, note that "insufficient" weight gain during the 2nd trimester only was predictive. Being below the average during the 3rd trimester did NOT have detrimental effects. 
• "Excessive" weight gain (defined as above the maximum as recommended by 2009 IOM) correlated with higher risk of c-section and large for gestational age babies. "Excessive" weight gain during both the 2nd and 3rd trimesters was harmful.

(Data obtained from PLOS Jan 2013)

Another interesting point is the variable weight gain recommendation in other countries. No surprise that they are lower elsewhere as compared to here in part due to smaller frames of women in some Asian countries and in part because Americans tend to think more and bigger is better (often to our detriment).

• Japan weight gain for normal weight women- 15-26 lbs
• UK weight gain recommendation is up to 27 lbs (Interestingly, one site's first comment was "first and foremost, it is important to accept that you are going to put on weight during pregnancy", quite contrary to the American view of "woo-hoo, bring on the ice cream, I'm eating for two!")
• France- 19-26 lbs
• S Africa, Ghana- 24-35 lbs

Finally, here is a estimated breakdown of where pregnancy weight gain goes. Not sure how they came up with this but I doubt is was from rigorous scientific study:

• Baby: 7-8 pounds
• Placenta: 1-2 pounds
• Amniotic fluid: 2 pounds
• Uterus: 2 pounds
• Maternal breast tissue: 2 pounds
• Maternal blood : 4 pounds
• Fluids in maternal tissue: 4 pounds
• Maternal fat and nutrient stores: 7 pounds

Source: American Pregnancy.org

Bottom line for healthy weight women: Stick with the recommendation, but feel comfortable that it's perfectly safe to stay at the lower end of the weight range. 

Bottom line for overweight and obese women: Plan to lose weight BEFORE becoming pregnant. Get healthy first before bringing a little one into the mix! If you do get pregnant while overweight/obese you must calorie count and stay active and be vigilant about minimizing weight gain.

Bottom line for me: It's normal to gain the most during the 2nd trimester. So I should be/can be careful from here on out. I'm up 14 lbs now. As long as I ensure I do not gain more than 1 lb a week b/t now and the end, both me and the baby should be a-okay. While I'm not going to start weighing myself daily, or restricting my food intake, I AM going to start counting my calories from time to time as a way to keep tabs on things and just keep myself in check. People in general (and me in particular) tend to eat more reasonable portions of healthier foods while tracking their intake. So that will be my step to avoid complacency during the next 12 weeks. That and continuing to have aggressive exercise goals (though they will change probably on a weekly basis), including my least favorite workouts of all- weight training. If I can turn some of this new found fat into muscle it will still be weight gain, right? :)