Insulin resistance

Insulin is a hormone produced by the pancreas that regulates your body’s blood sugar levels. If you have resistance to insulin, this means that your body’s cells don’t react to this hormone as they should and can’t convert blood sugar into energy. Consequently, the pancreas makes more and more insulin. When the pancreas can’t make enough insulin to control blood sugar, high glucose (hyperglycemia) can occur.

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Impact of insulin resistance on fertility

Insulin resistance can affect female fertility in many ways. It can reduce ovarian function, slow egg maturation, and cause infrequent ovulation due to imbalances of testosterone and estrogen. High blood sugar and insulin resistance can also lead to birth defects.

Potential causes of insulin resistance

Several factors may trigger insulin resistance or increase the risk of developing it, such as:

• Being overweight (particularly having excess weight around the stomach)
• Physical inactivity
• Diet high in processed, high-carb foods and saturated fats
• Family history of type 2 diabetes mellitus
• Certain medications (steroids, anti-psychotics, and HIV medications)
• High blood pressure and cholesterol
• Personal history of gestational diabetes, heart disease, or stroke
• Polycystic ovary syndrome (PCOS)
• Cushing’s syndrome
• Hypothyroidism (underactive thyroid)
• Genetic conditions
• Sleep apnea or sleep deprivation
• Smoking

Symptoms of insulin resistance

Insulin resistance normally doesn’t cause physical signs. But high blood sugar may have the following symptoms: 

• Increased thirst and hunger
• Frequent urination
• Blurred vision
• Headache
• Tiredness
• Weight loss
• Recurrent vaginal and skin infections
• Wounds that heal slowly

Diagnosis of insulin resistance

To diagnose insulin resistance, healthcare providers take several factors into consideration. They will check your medical and family history, do a physical exam, and run some tests. One of these tests isthe fasting blood glucose test, which measures your blood sugar level after not eating or drinking anything for 8-10 hours. The A1c test is another diagnostic test that measures your average level of blood glucose across the previous 3 months.

Treatment to improve fertility

The good news is that you can greatly improve insulin sensitivity and fertility while preventing prediabetes and type 2 diabetes by making some key lifestyle changes. Research shows that when overweight people lose 10% of body weight through regular exercise and eating a healthy diet, insulin sensitivity can improve by over 70%. 

When it comes to nutrition, aim to incorporate more plant-based foods into your meals, as these can improve insulin sensitivity, and less meat, which increases insulin resistance and raises the risk of gestational diabetes. For more nutritional advice, check out our articles on fertility foods for women and dietary tips for PCOS, and book a consultation with a LEVY nutritionist. You may also want to check your blood sugar after eating to learn how specific foods affect your glucose levels. 

A doctor may also prescribe metformin, a diabetes medication, to improve insulin sensitivity and prevent diabetes. Metformin can help women with PCOS and insulin resistance ovulate and reduce the risk of miscarriage.

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