Materials, products and services - the Green Guide Online provides details of the life cycle environmental impacts of construction materials and components, and the Green Book is a free online database of products and services.
Spermicides are used globally for birth control, with or without condoms. As the only means of birth control, spermicides are rarely effective. However, in conjunction with condoms, spermicides are somewhat effective in birth control.
Hormonal contraceptives work by: 1  Suppressing the release of hormones that trigger ovulation; 2  Stimulating production of thick cervical mucus, which prevents sperm survival and ability to travel to a ripe egg in the fallopian tube in the event that ovulation does occur;