The researchers from Auckland University in New Zealand, suggest that daughters experience puberty earlier if their mothers have a high fat diet while pregnant.

Experts suspect that the early onset of puberty may be linked to a range of problems from obesity, to depression in teenage years along with a higher risk of breast cancer as they have more menstrual cycles.

Although the research was carried out on rats, the research team believe the findings have relevance for women.

Dr. Deborah Sloboda, the lead author of the study, from the Liggins Institute at Auckland University, says the onset of puberty was much earlier in all the rats whose mothers had a high-fat diet, compared with the offspring of rats that ate a regular diet.

Then later in life those rats also had a higher amount of body fat than the controls did, even if they ate a regular diet while young.

The study showed that among the adult rats that had a maternal high-fat diet, there were alterations in the sex hormones, including increased levels of the ovarian hormone progesterone in females.

Dr. Sloboda says research suggests that a combination of prenatal and postnatal influences in girls can affect the onset of menstruation and a maternal high-fat diet possibly influences reproductive maturation and reproductive capacity in adult offspring.

The research was presented at The Endocrine Society's 90th Annual Meeting in San Francisco and was supported by the Health Research Council of New Zealand, National Research Centre for Growth and Development, and the Maurice and Phyllis Paykel Trust.

The researchers then checked whether those who had high fasting glucose - with or without a formal diagnosis of diabetes - were more likely to develop depressive symptoms by the end of the study.

The researchers found that patients treated for diabetes were about 54 percent more likely to develop elevated depressive symptoms than those without diabetes.

A surprising result the researchers are unable to explain was that those with prediabetes or untreated diabetes were about 25 percent less likely to develop elevated depressive symptoms than people with normal fasting glucose.

Dr. Golden, an associate professor of medicine and epidemiology at Johns Hopkins, speculates that depression may lead patients to develop behaviours that trigger diabetes or make it worse, such as overeating, not exercising or smoking.

Similarly, keeping up with the often extensive treatment regimens to care for their diabetes may make patients ™ depression worse.

Dr. Golden says having both diabetes and depression can make it difficult for patients to get good clinical outcomes and understanding how one condition might lead to another could improve treatments for both problems.

The study is published in the June 18th issue of the Journal of the American Medical Association, and was supported by grants from the National Heart, Lung, and Blood Institute.