NEW ORLEANS -- Results from a small study suggest that women whose diets consist of at least 25% protein may have more successful outcomes when undergoing assisted reproduction.
Two-thirds of the women who ate protein rich diets (32 of 48) achieved pregnancy versus 31.9% (23 of 72) of controls (P<.0005), said Jeffrey B. Russell, MD, of the Delaware Institute for Reproductive Medicine, in Newark, Del.
And the results were even more impressive when a high protein intake was combined with carbohydrate restriction (less than 40% of daily diet) as pregnancy rate climbed to 80%, in that subset Russell and colleagues reported at the American Congress of Obstetricians and Gynecologists meeting here.
Action Points
- Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.
- In this study, significant increases in fertility were found in patients reporting a high protein diet particularly when combined with dietary carbohydrate restriction and this relationship was independent of BMI.
"People talk about obesity and BMI, about not getting pregnant when they are overweight, but we had some patients who were healthy, 110 to 115 pounds, and they were making terrible quality embryos," Russell told 鶹ý. "They were thin, young and healthy, but couldn't get pregnant."
Patients reported eating "pasta, potatoes and bread," Russell described. He and his colleagues recommended they try meatballs, chicken and eggs. To accommodate vegetarians or vegans, Russell and his colleagues recommended protein in Greek yogurt, egg whites and tofu.
He said Asian women, who have a higher rate of infertility, were advised to reduce their rice intake and replace it with soy products and nuts.
"When you scale back the rice, you can see an improvement in egg quality," he said. The lessons of this study might be applied to diabetics, he said, who have the highest miscarriage rates, highest abnormality rates, and the highest birth defects and stillborn rates.
"This small study suggests that the impact of diet, protein content in particular, is an important factor in embryo quality and pregnancy rates," said James A Grifo, MD, PhD, NYU Langone Medical Center.
"It begs that more studies be done to further our knowledge in this area. However, in the absence of those studies there is no harm in adhering to a diet that has 25% of daily caloric intake from protein. In addition, prenatal vitamins, adequate folic acid and adherence to the basic principles of a healthy diet rich in fresh fruit and vegetables with the inclusion of healthy unsaturated fats as well as unrefined complex carbohydrates is a recipe for a healthier lifestyle," Grifo added.
The 120 women, who were recruited from an assisted reproductive technology program from January 2010 through December 2011, were asked to keep a 3-day dietary log before in vitro fertilization.
The data were analyzed for daily percentage of proteins, carbohydrates, and fat content, age, BMI, diagnosis, follicle-stimulating hormone, luteinizing hormone, and estradiol levels, Russell said.
Statistical analysis was performed with a two-proportion Z test and two-sample T test.
Russell said the study was limited by the imprecision of obtaining an exact recording of each calorie each patient consumed over a three-day period.
"The study makes sense that lower fertility is affected by diet," commented Ira Frye, MD, of Geisinger Wyoming Valley Medical Center in Danville, PA. For many obese patients, he said, their diet is based on "bad carbs" such as "fries and chips."
Fruits, vegetables, and lean meats will produce better quality sperm, as well as better quality eggs, he said.
Disclosures
The authors reported no conflicts.
Primary Source
American Congress of Obstetricians and Gynecologists
Source Reference: Russell J, et al "Daily protein content correlates with increased fertility and pregnancy outcome" ACOG 2013; Abstract Poster 96.