2TTO Ch5.8

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

Paragraph 5.8 Birth control

Lesson goals

• You can name several ways of preventing pregnancy
• You can name several hygiene products for women during menstruation

Birth control

• Birth control = preventing pregnancy from happening
• Methods of controlling birth are called contraceptives
• There are many ways of preventing pregnancy: providing a barrier between the sperm and the egg, preventing the ovulation, and preventing the zygote to nestle in the uterus

Preventing the ovulation

• This is done via hormones
• As you know, the menstrual cycle and ovulation are controlled by hormones
• If you prevent these hormones from working, no mature egg will develop and ovulation will not happen
• The hormones used for this are progestogen (not progesteron!) and estrogen

Preventing the ovulation

• The most well-known hormone-contraceptives is  'the pill'
• This contains hormones that influence the menstrual cycle, which go to the uterus via the bloodstream
• Other options are the NuvaRing or an IUD, which both release hormones into the uterus.

Barrier between sperm and egg

• Preventing the sperm and egg to come together is another way of contraception
• The most well-known one is the male condom, which is wrapped around the penis and prevents the sperm from entering the uterus
• Another version is the female condom, which can be wrapped around the cervix
• Both versions of the condom are quite reliable, however they might rip apart

Preventing the zygote from nestling

• IUDs (Intra-Uterine-Devices) are devices that a doctor places inside the uterus. This device makes sure that a zygote can never nestle in the uterus. 
• Additionally, IUDs can contain hormones to prevent the ovulation as well
• With some IUDs, women still have a menstruation. With others, they don't (the hormone ones)

What if you don't want (more) children?

• If people do not want children permanently, they have the option of permanent contraceptives.
• This involves closing off the oviducts in women or the vas deferens in men, preventing eggs or sperm from ever coming out.
• This, however, is a choice people often make when they're older, and are sure that they don't want children. Additionally, people who have children but don't want more, can choose this option

What about preventing pregnancy without using any devices?

• Cotus interruptus means 'pulling out' before ejaculation. This is, however, not very safe since sperm cells sometimes already come out before actual ejaculation
• The calendar method is when a woman tracks her menstruation and ovulation, and bases on that whether she can have sex, since pregnancy can only occur when she's ovulating. This is also not very reliable, since the cycle can change monthly, and sperm can survive for some time inside the body

That was it!

• Homework = read and summarize paragraph 5.8, and finish all exercises  (40-49)
• Next week, some people will move on to paragraph 5.9, while others will come to school.
• Preparation for school: ask questions about any sexuality/sex-related topic anonymously on https://padlet.com/mcuijpers2/zbew5o01ynlxl0w7
• Preparation for staying at home: read paragraph 5.9