The buck deposits billions of sperm just at the opening of the cervical canal.
The vagina is a hostile environment for sperm so they must quickly enter the cervical canal to survive.
The vagina is acidic (pH 4.0)
Transport of Sperm
Sperm enter the cervical canal within a few minutes after mating.
The moderately alkaline (pH 8.4) cervical canal increases the mobility of the sperm.
Most defective sperm are filtered out in the cervix.
As sperm move through the uterus they begin to go through changes which prepares them
for fertilizing the egg.
At pH 7.8 the environment of the uterus is almost neutral.
Once the sperm reach the oviduct their number is much reduced.
Only about 1,000 to 10,000 sperm make it to the isthmus of the oviduct.
In the oviduct the sperm go through further modification.
This process is called capacitation and is necessary for the sperm to fertilize the egg.
The egg survives only about 24 hours after ovulation.
Sperm can survive as long as 48 hours after release into the female's reproductive tract.
Only 10 to 100 sperm are present in the ampulla but 90% of the time fertilization
of the egg will take place.
The egg is held at the junction of the ampulla and oviduct waiting for the sperm to reach it.