Obesity is characterised by an excess of fat cells, formally called adipose cells. Adipose tissue is actually part of the endocrine system of the body, meaning that it is hormonally active.
These cells lead a strong role in homeostasis and metabolism. They do this by secreting adipokines – bioactive, pro-inflammatory molecules.

Specific to fertility in the obese population, these molecules affect the way the brain and body interact with the ovaries (known as the hypothalamic-pituitary-gonadal axis).
Imbalances in this system can lead to menstrual irregularities, ovulation problems and infertility.

Weight loss, specifically large amounts as we see in the post-surgical population, improves these hormone imbalances. This in turn improves ovulation and enhances the potential for contraception.
In these surgical patients we typically see a rapid return to fertility, on average within 1-5 months. The rate of increased fertility often corresponds to the degree of weight loss.

It can also lead to a state of hyperfertility, meaning a person changes from infertile to a state where they are more likely then the average person to fall pregnant. It is essential to use contraception during this time to prevent falling pregnant before it is safe to do so. This ‘unsafe’ period usually lasts until the weight loss has plateaued, typically 18-24months.

It is also extremely important to stay in close contract with your bariatric team during pregnancy to ensure adequate nutrition and avoid complications.