Proper nutrition and lifestyle prior to and during pregnancy are extremely important for the developing foetus and influence the course of pregnancy and health of the pregnant woman. Currently, the age of women in the reproductive period varies between 15 and 49 years of age. Because the reproductive period spans such a wide age range, there are different problems typical for a given age, which affect procreation. It is of key importance that women planning to become pregnant change their lifestyles and follow a proper diet about six months before the conception. A rational diet should include five meals a day and be balanced in terms of nutritional value. The number of calories in the diet should be adjusted individually for each woman with regard to the type and frequency of physical activity. Special attention should be paid to variety in the diet. While selecting products for the diet, the following should be taken into consideration: allergy and intolerance, the necessity of using low-GI food. It is also important for a woman planning pregnancy to pay attention to the type of fat used. It is necessary to eliminate trans fats often contained in industrially-produced pastries, sweets, chips, fast foods, powdered soups, hard margarines. These fats should be replaced with products rich in mono- and polyunsaturated fatty acids. While choosing protein products women should include various sources of protein, both animal and plant. Thus, the diet should contain low-fat poultry, veal, as well as limited amounts of low-fat pork and beef, fish – mainly sea fish, eggs and leguminous plants (bean, pea, lentil, chick-pea, soya). Products rich in complex carbohydrates should make up more than 50% of the energetic intake. It is advisable to choose whole-grain bread, buckwheat, millet, pasta, cereals. The intake of protein, fat, carbohydrates, vitamins and minerals and fibre should comply with nutrition standards and be adjusted to vitamin and mineral deficiencies, age, physical activity. In case of a poorly balanced diet or vitamin and mineral deficiencies it is recommended to take advice from the doctor about the type of supplement and its dosage. Not less than three months before conception, each woman should take 0.4 mg of folic acid daily. In the period from September to April supplementation with vitamin D3 is also advisable. The dosage should be individually adjusted after testing D3 vitamin level in blood. A well-balanced diet provides the appropriate amount and quality of protein, fat, carbohydrates and fibre, and includes products being sources of vitamins and minerals. A diet rich in products containing B vitamins, folic acid and its derivatives, antioxidants, iron and deprived of excessive caffeine and alcohol seems to be of great importance in the prevention of infertility. For practical reasons, it is important that both doctors and other persons involved in the counselling related to period prior to pregnancy are aware of healthy eating habits and women’s needs for energy, nutrients, vitamins and minerals before conception.