Aim: to evaluate the qualitative characteristics of a sleep in pregnant women in the 3rd term of the physiological pregnancy by a questionnaire survey. Materials and methods: we have demonstrated questionnaire survey data of 400 pregnant women (mean age 27,5±8,2 years) in the 3rd term of pregnancy. Questioning conducted using the scale PSQI (PITTSBURGH SLEEP QUALITY INDEX — Pittsburgh Sleep Quality Assessment Questionnaire), EPWORTH SLEEPINESS SCALE (sleepiness questionnaire Epfort’s) and screening questionnaire to identify obstructive sleep apnea. Results: we have determined that 78% of pregnant women to complain about sleep disorders, namely obstructive sleep disordered breathing, insomnia, «restless legs» syndrome, and combinations thereof. The frequency of sleep disorders increases as pregnancy progresses. Obstructive sleep disordered breathing increases with 10,12% in the 1st term to 31,7% in the 3rd term, insomnia — from 14,3% in the 1st term to 37,6% in the 3rd term. In pregnancy increases of sleep latency (from 14,3 to 44,9 minutes), and reduced the duration of a sleep (from 8,7 to 7,8 hours). Conclusions: high frequency of sleep disorders in pregnancy requires early pathogenetic prevention of pathological conditions, both in the mother and in the fetus.