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After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
In 2010, opiate painkllers, such as morphine, OxyContin®, and Vicodin®, were tied to almost 60% of drug overdose deaths.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Bisphosphonates were first developed in the nineteenth century. They were first investigated for use in disorders of bone metabolism in the 1960s. They are now used clinically for the treatment of osteoporosis, Paget's disease, bone metastasis, multiple myeloma, and other conditions that feature bone fragility.
Only 12 hours after an egg cell is fertilized by a sperm cell, the egg cell starts to divide. As it continues to divide, it moves along the fallopian tube toward the uterus at about 1 inch per day.
![An emergency medical technician positions defibrillator paddles on the chest of a supine male patien](https://biology-forums.com/gallery/47/medium_14755_10_09_12_7_23_56_85331131.jpeg)
![(a) Male competition can be fierce. (b) This male baboon has bite wounds suffered in competition wit](https://biology-forums.com/gallery/47/medium_269691_26_01_15_5_55_25_204431297.jpeg)