We obtained data recorded in the Danish medical birth registry on all women with a prolonged pregnancy in the first delivery and in a subsequent delivery, during 1980-94, and a 5% sample of all women with two or more pregnancies recorded in the period 1980-92 (only the first two deliveries were used for analysis). The information on gestational age in the registry was obtained from birth record...

Background: Detection of sperm parameters based on conventional methods, immediately after thawing, have been revealed sperm capacity to in vivo and in vitro fertilization. But this evaluation is not fully reliable because of long journey of sperm during female genital tract to reach the oocyte and fertilize it. Therefore, analyzing postthawed sperm parameters after incubation is more beneficia...