Atkins diet may hurt women's chances of conceiving

The Atkins diet may reduce a woman's chances of becoming pregnant, according to new research.

High-protein diets such as the Atkins regime are linked to increased rates of pregnancy failure in the early stages of conception, scientists have found.

And they warn that women who are trying to become pregnant should not adopt protein-rich diets.

The medical world has been divided over whether the low-carbohydrate, high-protein Atkins diet works and there have been concerns over potentially dangerous side-effects.

The latest research was presented at the annual meeting of the European Society for Human Reproduction and Embryology in Berlin this week.

Scientists from the Colorado Centre for Reproductive Medicine in the United States fed laboratory mice on a 25 per cent protein diet and compared them with mice on a normal diet. Both sets of mice were then impregnated.

The mice on increased protein had a fourfold increase in levels of the chemical ammonium in their reproductive tracts. Ammonium has been linked to problems in mice embryos, such as delayed development and genetic defects.

The embryos from the high-protein mice had fewer cells and a higher rate of cell death. This is a crucial stage in embryonic development, since it is just before the embryo attaches to the inside of the womb. If it does not implant, pregnancy cannot occur.

The early-stage embryos from both sets of mice were then implanted into a third group that had been fed a normal diet.

Only 65 per cent of embryos from high-protein mice developed into a foetus, compared with 81 per cent of those from the lower-protein group.

While the mice were fed a 25 per cent protein diet, Atkins adherents tend to eat 35 per cent protein during the first induction and weight-loss stages of the diet, and are then recommended to remain at 25 per cent for the "maintenance" phase, which can last all their lives.

Lead researcher Dr David Gardner said: "It is conceivable that people who have protein intakes greater than 30 per cent may have problems conceiving. These findings mean that it would be prudent to advise couples who are trying to conceive to ensure that the woman's protein intake is less than 20 per cent of their total energy consumption."

Since it was developed more than 20 years ago, the Atkins diet has achieved global fame but has also been dogged by controversy.

But the multimillion-dollar company Atkins Nutritionals, which has run the empire since the death last year of its creator, Dr Robert Atkins, insisted the regime was safe.

Medical director Dr Stuart Trager said: "It is important to note that there was no mention of carbohydrate control in the research conducted by Dr Gardner.

"The study subjects were mice, which are herbivores. Whether or not these findings or effects would apply to humans, who are omnivores, is unknown.

"The positive role of controlled-carbohydrate nutrition has been well established clinically in women who are either overweight and/or not ovulating normally.

"In addition, there are more than 28 studies focused specifically on the Atkins Nutritional Approach, each of which demonstrates that on average the subjects experience improvements in both weight loss and overall health."

- INDEPENDENT