Hi, thanks for asking in Healthcare Magic. Femilone contains Desogestrel and Ethinyl Estradiol. Generally COMBINED oral contraceptives can result in weight gain. Both estrogen (water retention) and progesterone (androgenic action) are responsible for the weight gain. Desogestrel in Femilone is a progesterone preparation. It is devoid of the androgenic property of most other progesterones. So it does not result in weight gain. But as a progesterone, it results in severe nausea, loss of appetite and bloating sensation in stomach all of which can contribute to your loss of weight. You should stop Femilone at least 6 months before you plan for your pregnancy. Although it may take only 1 to 2 months for the return of ovulation and fertility to in some persons ovulation may be delayed. Weight gain after stopping the pill is not noted in many people but in your case the improved appetite that may occur on stopping the pill may contribute to weight gain. Loss of 4 kg in a span of 3 years is not a drastic weight loss and may not necessarily be due to pill and could be due to other factors like stress. Being hormonal preparations, both estrogen and progesterone can result in increase in blood sugar level (pre diabetic) that can also contribute to weight loss. However since you are taking the pill for 3 years, it is better you consult your treating Dr to rule out other causes of weight loss. I hope this helps.