Evaluating the effects of metformin and exenatide on pregnancy rate and pregnancy outcomes in overweight or obese infertile women with PCOS.

This study compared the effects of metformin (Glucophage) and exenatide (Byetta) on pregnancy rate and pregnancy outcomes in overweight or obese infertile women with polycystic ovary syndrome (PCOS). The data showed that 12 weeks of exenatide treatment before pregnancy improved spontaneous pregnancy in these women.

PCOS is a common cause of female infertility which can be challenging to treat. It is usually associated with impaired ovulation, high levels of testosterone, and irregular menses.

PCOS is also connected to obesity and resistance to the hormone insulin. Insulin is responsible for controlling the level of glucose (sugar) in the blood. Some treatments for PCOS work by improving insulin resistance. This includes metformin which improves insulin resistance in the liver and the body. Metformin can make ovulation more regular for women with PCOS.

Exenatide is a diabetes medication. Exenatide mimics a hormone the gut releases after eating and increases the amount of insulin the body releases. Past studies have found that exenatide improves blood glucose control and can help reduce body weight. However, whether exenatide improves insulin resistance and pregnancy outcomes compared to metformin in overweight or obese infertile women with PCOS is still under investigation.

This study involved 160 overweight or obese infertile women with PCOS. Patients were randomly assigned into 2 groups. 80 women received metformin. 80 women received exenatide. After 12 weeks all patients received metformin alone until pregnancy was confirmed and followed until delivery.

After 12 weeks, body weight parameters including body mass index (BMI; a measurement of weight in relation to height), insulin resistance, and waist circumference in relation to hip circumference were all improved in both groups. 

At week 24, significantly more women (29.2%) in the exenatide group conceived spontaneously versus 14.7% in the metformin group. At week 64, total pregnancy rates were 79.2% in the exenatide group and 76% in the metformin group. This difference was not statistically significant.

There was no significant difference in pregnancy outcomes between the two groups. Spontaneous pregnancy was positively associated with body weight reduction and improvement of insulin resistance in either group.

Side effects were similar in both groups and were related to the digestive tract.

This study concluded that 12 weeks of exenatide treatment before pregnancy improved spontaneous pregnancy rate with significant weight reduction and improvement of insulin resistance in overweight or obese infertile women with PCOS compared with metformin treatment. However, it did not improve the total pregnancy rate or pregnancy outcomes of women who successfully conceived.

The sample size was very small. This study only included Chinese patients treated at a single institution. Larger studies are needed to validate the findings.