Sperm survival, in terms of numbers, motility, viability, and metabolic activity, was studied in vaginal washings obtained daily from 22 healthy, fertile, married women during one complete menstrual cycle. The numbers of sperm (counted on Papanicolaou-stained filters) were never large compared to the number of sperm in a single ejaculate. Forty-eight hours after intercourse, only 6% of the specimens showed any evidence of sperm. Motile sperm were observed in only six of 94 postcoital specimens examined within 12 hours after intercourse. Lack of sperm in specimens collected after reported intercourse was associated with contraceptive practices other than the rhythm method, which most of the subjects were using. Fluorochromatic studies of recovered sperm treated with acridine orange indicated sperm viability and phase contrast studies of sperm treated with tetrazolium salts revealed metabolic activity. Our data on sperm motility, numbers, and staining reactions support the conclusion that the small number of sperm that remain in the vagina after intercourse quickly become inactivated.
PIP: Number, motility, viability, and metabolic activity of sperm were studied in vaginal washings obtained daily from 22 fertile, married women during 1 menstrual cycle. Sperm were recovered in 73% of the samples examined within 12 hours postcoitus. Motile sperm were observed in only 6 samples collected within 12 hours postcoitus. All sperm collected 24 hours postcoitus were nonmotile. Numbers of sperm ranged from 0 or very few to nearly 1/2 million/cubic cm. Most samples were in the range of 0-30000 3-36 hours postcoitus. Formazan-positive stain reactions observed in 5% of the samples were weak, indicating no metabolic activity. Nonmotile sperm showed some viability through green fluorescence in the acridine orange fluorochrome reaction. When data were adjusted for the use of contraceptive techniques other than rhythm (coitus interruptus, condom), sperm were recovered in almost every instance of reported coitus. It is concluded that the small number of sperm remaining in the vagina following coitus quickly become inactivated.