The cervical cap is one of the least common forms of contraception. It is a latex or silicone covering that fits over a woman's cervix, in order to prevent sperm from entering the uterus. The effectiveness of this method depends upon which type of cap is used, who is using it, and whether or not it is used consistently and correctly. For example, the annual failure rate of the cervical cap for women who have given birth is between 32 and 26 percent for typical and perfect use. However, among women who have never given birth, it is between 16 and 9 percent. The difference in the rates is because childbirth alters a woman's cervix, making the cap less effective. However, not all women can use this method of birth control. In fact, cervical caps do not fit 20-40 percent of women.
Historically, many cultures have attempted to create devices that cover the cervix as a method of birth control. These primitive barrier methods were made from everything imaginable, including beeswax, seaweed, lemon halves, paper, tree bark, tree roots, rock salt, and other items.
The potential side effects of the cervical cap are few, but may include urinary tract infection, toxic shock syndrome, and allergic reaction. Since the device blocks the sperm from entering the uterus, the woman is also deprived of its beneficial effects. For example, a man’s seminal fluid includes at least two dozen ingredients, including estrogens, follicle-stimulating hormone, luteinizing hormone, testosterone, transforming growth factor beta, and several different prostaglandins. During intercourse the female’s body absorbs these, and they aid the health of the woman.
Furthermore, when a man and woman have intercourse, the woman’s body becomes accustomed to the man’s sperm. In medical terms, her immune system develops a gradual tolerance to the antigens on his specific type of sperm and seminal fluid. For several hours after intercourse, a woman’s immune cells will collect and transfer a man’s foreign proteins and entire sperm cells from her cervix to her lymph nodes, where her immune system learns to recognize his genes.
However, if the couple decides to use a barrier method of birth control for an extended period of time before having children, the womb will not be accustomed to the sperm, and the woman’s immune system may treat them as foreign bodies. This can disrupt the delicate balance of hormones and cause the woman’s blood vessels to constrict, leading to higher blood pressure in the expectant mother. This condition (preeclampsia) occurs in about 5 to 8 percent of all pregnancies and can lead to premature delivery of the baby. Unfortunately, pre-term babies are more likely to experience learning disabilities, cerebral palsy, epilepsy, blindness, and deafness. Preeclampsia can also be dangerous for the mother: it is the third leading cause of maternal death during childbirth.
It has been demonstrated that a man’s semen offers a protective effect against preeclampsia, because it makes the woman’s immune system more likely to recognize his baby. According to The Journal of the American Medical Association, preeclampsia is more than twice as common in women who used barrier methods of contraception. So in a certain sense, couples who use the cervical cap are having unprotected sexual intercourse, because the man is not protecting the woman’s body with the beneficial effects of his semen. As you can see, a woman’s body is created to work with a man’s in a precise way. When we tinker with God’s designs, and try to flip fertility on and off like a light switch, we create more problems for ourselves.
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