Investigated group comprised pregnant women after sterility treatment, which underwent obstetrical care in Institute of Obstetrics and Gynaecology Medical Academy of Łódź in years 1998-2000. In the first group were 25 pregnant women after endometriosis treatment, the second one 23 healthy pregnant women. At term were performed ultrasound examinations (biometry and estimated fetal weight) than were assessed neonatal weight in both groups. There were found the similar mean age in both groups, but in the group after treatment more women in age over 30 years were observed (not significant). The higher weights were observed in the group of healthy pregnant women in ultrasound fetal estimation before delivery (about 343.5 g) and neonatal weight after delivery (about 407 g) but without significance. There is possibility of the better vascular development in the feto-maternal circulation in the course of pregnancy in healthy women than after endometriosis treatment, but for the correct conclusions should be made further research on larger collectives. Ultrasound assessment is a useful method in prenatal diagnostic with possibility of precise analysis of the fetal development.