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Creative Research Center

The Implications of Weight Gain in Pregnancy: A Scientist’s Personal Experience Inspires Her Research to Help Future Generations – by Diana Thomas

Posted in: Guest Essay

CRC Editor’s Note – On June 5th, the very same day we received Diana Thomas’s essay, I picked up The New York Times and saw this article on the front page: Growing Obesity Increases Perils of Childbearing.

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I had always been athletic and slim if even on the overly skinny side until about 12 years ago.  I wasn’t alarmed when I first started gaining weight, as I was confident that I could easily lose the extra pounds if I needed to.  Unfortunately, I was not aware how much my new sedentary life as a professor and mother would make it difficult to achieve my previous healthy weight.  As it became increasingly more challenging to get in and out of my two-door Honda Civic, I realized it was time for action.  I started my new position as an assistant professor at Montclair State University in September 2000 and began the hard work of losing almost 70 lbs of excess weight.

As I started shedding pounds, I began to mathematically investigate the mechanics behind how humans lose and gain weight. Pam Delaney (Biochemistry).

John Stevens (Math), and I collaboratively developed our first model that predicted weight change, which I primarily used for engaging students in the classroom and answering questions about weight change for family and friends.

Student interest in the topic was high and based on a student project, Baojun Song (Math) and I developed the first model simulating weight change during starvation.  During this time, I lost over 60 lbs of excess weight and just as I stepped back into pre-pregnancy clothes, I discovered I was carrying my second child.

Desperately concerned about going through a weight loss process again, I carefully monitored my weight gain during pregnancy, ate well, swam at Panzer pool or worked out on the elliptical daily.  Upon reading JF Clapp, M.D.’s Exercising through your Pregnancy

I began to think about the dynamics of weight change during pregnancy resulting from changes in exercise and diet.  I contacted Dr. Clapp in 2004 and we collaboratively developed a model for fetal growth in utero based on maternal exercise and diet.  The paper, which appeared in Royal Society Publication set in motion a series of events that permanently altered the course of my research career.

Attention from the publication resulted in current collaborations with Steven Heymsfied, M.D. and  Corby Martin, Ph.D.

Dr. Heymsfield is an expert in human body composition who has studied weight change from a quantitative point of view for over 30 years. Dr. Heymsfield and I have looked at how body composition is a mathematical function of race, gender, age and height using a large cross-sectional data set representative of the current US population. This function is at the core of all the weight loss models we have developed.

Dr. Martin is a behavioral psychologist who is investigating adherence to lifestyle changes that promote weight loss at Pennington Biomedical Research Center.

Dr. Martin and I collaboratively designed a model we use to monitor patient adherence to diets.  The idea we developed is simple and effective. Applying our validated math model, we generate a weight loss curve for each individual patient based on their prescribed diet. If the patient is non-compliant, their actual weight loss will not follow the trajectory predicted by the model offering an opportunity for immediate interventions by the clinical staff.

These collaborations and others and the ongoing questions they have generated, have led me far away from mainstream mathematical research.  Instead of working in an office with pencil and paper, I am now running clinical trials which will provide additional mathematical insight into weight gain and loss in individuals.

I am currently at the end of my first clinical trial with St. Barnabas Medical Health Center on placental volume and fetal growth during pregnancy.  We have enrolled 12 pregnant women in the study and are investigating how their placenta grows during gestation by conducting a 3-D ultrasound every five weeks of the pregnancy. There is a growing body of evidence that placental volume is controlled by maternal diet and exercise.  Placental volume has been also correlated to birth weights and the baby’s percent fat.  Larger infant percent fat mass has been connected to childhood obesity and therefore mathematically correlating these seemingly independent pieces of gestation is highly significant.

My mathematical background makes me a unique member of my research team which consists of physiologists, nutrition scientists, medical health professionals, and psychologists.  More important, however, is that I am the only individual on our research team that has lost a significant amount of weight and this gives me a personal insight into what challenges our subjects encounter in their weight loss efforts.

As I examine the data, I cheer their hard work and hope to simplify and enhance interventions so that they make the most impact possible for individual healthy weight maintenance.

Diana Thomas, PhD, Associate Professor of Mathematics, Montclair State University