The normal duration of pregnancy - 290-294 days from the moment of conception until rodov. Odnako, in some cases, the physiological pregnancy varies considerably. In connection with this distinction:
miscarriage
prolongation of pregnancy.
Under the miscarriage spontaneous miscarriage understand it in different terms from conception to 37 weeks. The frequency of this complication varies from 10 to 25% and has no tendency to decrease. Miscarriage before 28 weeks. referred to as spontaneous abortions (abortions). Termination of pregnancy in terms of more than 28 weeks - to premature birth (premature birth of pregnancy).
Prolongation of pregnancy means the untimely (late) the emergence of labor, with its development are frequently observed violations of the uterine contractile activity, which leads to an increase in the number of surgical interventions, for intrauterine fetal suffering and increased perinatal mortality. The frequency of prolongation of pregnancy ranged from 3 to 7%.