The way of women’s nutrition before and during pregnancy affects the pregnancy process, birth and child’s health in a future. The properly balanced diet should provide all nourishing elements in the amounts that cover the demand of mother’s and child’s organism.The aim of the study was to evaluate the diets of women during pregnancy and lactation. Based on analysis of the literature and our own observations; formulated research hypothesis, which says that there are differences in dietary habits of pregnant and lactating -depending on the weight before pregnancy. The research tool was an anonymous questionnaire, which consisted of three parts. The first part of the questionnaire included sociodemographic questions, the second part related to the health status of the respondents and pregnancy. Another part of the survey included questions about nutrition. The survey also included questions about risky behaviors. The study was conducted in 2009-2011 in the province of Malopolska. The inclusion criteria were age of maturity of the subject and written agreement to participate in the survey. Studies excluded women with abnormal course of pregnancy and childbirth, and common systemic diseases. The execution of the survey was approved by the Bioethics Committee of the Jagiellonian University No. KBET / B / 141/2011 dated on 01.07.2011 year.Surveys were conducted between 28-32 week of pregnancy. Respondents were subjected to a subsequent study between 8-12 weeks after childbirth. The control group women were classified on the basis of random selection. The final analysis of the data included surveys of 344 women who meet the established requirements of the research. The results were coded as prepared for the purposes of this paper based on Microsoft Excel. The results of a statistical study wasperformed using Statistica 10.0 GB (StatStof company). The results revealed that the diet of women surveyed during lactation compared to women during pregnancy has slight modification. It was also found that body weight in some aspects was associated with dietary choices of women surveyed. Canonical Analysis for groups of features (social situation, health characteristics, anthropometric characteristics, weight gain) showed that a group of variables characterizing anthropometric data explains 60.91% of the variation in a set of characteristics that determine the weight gain. The frequency and number of meals did not change. The length of gaps between the meal and their regularity remained unchanged. The frequency of eating fruits and vegetables has changed. Lactating women often ate boiled vegetables, and pregnant women often ate fruits and vegetables, often also drink fruit and vegetable juices. Pregnant women in relation to the lactation period often consumed milk and its products. In lactating women tend to consume lean meats and poultry. In contrast, the fish were eaten less than a few times a week. The consumption of cereal products deviate from the recommendations of experts. Fat intake between groups was at a similar level. An in-depth analysis of the cluster in terms of nutritional products eaten during pregnancy and lactation has shown that products whose consumption has been increasing in each of the analyzed clusters were sweet drinks milk, cottage cheese and smoked cheeses. ; Examined women hardly undertake action and healthy activities. A little more than forty percent of women surveyed pregnant or lactating; practice sport more than 1-2 hours per week. The remaining percentage of women in their spare time practiced on a small level. Physical activity in spare time during lactation related to walks with a child. The remaining percentage of women in their spare time practiced on a small level. Physical activity in leisure time during lactation was associated with walks (with a child). The results revealed that a hypothesis that pregnant women change their diet was not fully confirmed. Frequently changing diets of lactating women can be observed.Conclusions: 1. Nutrition and feeding habits of the surveyed women were only slightly modified.2. Body weight before pregnancy and weight gain during pregnancy remained little relation to dietary choices made by pregnant and lactating women. 3. Nutritional habits of women during pregnancy and lactation in many respects did not meet dietary recommendations of experts and may favor the presence of a nutrition disturbances.4. Pregnant women and lactating women compared to non-pregnant were often feeding in the line with the recommendations of experts. Women who were not pregnant nourish less regularly and often reached for not recommended and “rubbish” products. This group also more often presented risky behaviors 5. Nutrition models of surveyed women generally have not changed. The most differentiating nutritional behavior, allowing the isolation of three nutrition models was eating products and its frequency.6. Cancellation of risky behavior in the studied groups of women, in the field of alcohol and smoking, remained in connection with pregnancy and lactation period. 7. The health promoting activities of the surveyed women, physical activity, were at a low level part of a comprehensive low physical activity of Polish society. Supplementation with vitamin products was used more by pregnant women than those during lactation.