Video Transcript
The graph shows the effectiveness
of different methods of contraception when used perfectly and with typical use,
i.e., with possible human error. Which of the following statements
is correct? (A) The contraceptive injection is
less effective when used perfectly than both the combined pill and the
progesterone-only pill. (B) Perfect use of female condoms
is more effective at preventing pregnancies than typical use of the combined
pill. (C) Typical use of all hormonal
methods is more effective compared to typical use of barrier methods. (D) Perfect use of all barrier
methods is more effective than perfect use of hormonal methods.
This question asks us about the
effectiveness of different methods of contraception which is measured by how well a
certain method prevents pregnancy.
Contraception refers to the
prevention of fertilization of an egg by a sperm cell. There are many different kinds of
contraceptives that mainly include hormonal methods and barrier methods.
Hormonal methods typically involve
the use of hormones in order to prevent a mature egg from being released by the
ovaries. These methods also work to thicken
cervical mucus in order to prevent sperm from entering the uterus. Some examples of hormonal methods
for contraception that we could see in the provided graph are the combined
contraceptive pill, the progesterone-only contraceptive pill, and the contraceptive
injection.
On the other hand, barrier methods
of contraception work by physically preventing semen, which contains sperm, from
entering the female reproductive tract. This blocks fertilization from
occurring. Some examples of barrier methods of
contraception that we can see in the provided graph are male condoms and female
condoms. As you can see from our graph, the
effectiveness of each type of contraceptive varies, based on perfect use and typical
use.
Perfect use occurs when a method is
used correctly every time, so the effectiveness is often higher. Typical use factors in human error,
such as forgetting to take a contraceptive pill or incorrectly using barrier methods
of contraceptives, which is why the effectiveness is often lower.
You might notice that the
effectiveness for hormonal methods of contraceptives with typical use is still close
compared to perfect use. This is because human errors can
often be minimized, for example, by taking a contraceptive pill the next day after
forgetting one the day before.
Other hormonal methods, like a
contraceptive injection, offer more long-term protection that does not require daily
intervention, which is why they are so effective even with typical use. On the other hand, barrier methods
can easily be misused, which is why their effectiveness is lower and hovers around
75 percent with typical use.
Now, in order to answer our
question, let’s have a look at each answer choice.
In answer choice (A), “The
contraceptive injection is less effective when used perfectly than both the combined
pill and the progesterone-only pill” is incorrect. If we look at the perfect use
column for these contraceptives, indicated with the green dots above the columns in
the graph, we can see that the contraceptive injection actually has a higher perfect
use effectiveness.
In answer choice (B), “Perfect use
of female condoms is more effective at preventing pregnancies than typical use of
the combined pill” is incorrect. Although typical use of the
contraceptive pill is slightly lower than perfect use of female condoms, overall
they are very similar.
In answer choice (C), “Typical use
of all hormonal methods is more effective compared to typical use of barrier
methods” seems to be correct. Here are all the typical use
columns for hormonal methods, indicated with the green dots, and here are the
typical use columns for the barrier methods, indicated with the blue dots. Notice how they are both lower than
the hormonal methods. So, this answer seems correct, but
let’s take a look at the final option before making our final decision.
In answer choice (D), “Perfect use
of all barrier methods is more effective than perfect use of hormonal methods” is
incorrect. The barrier method columns for
perfect use are indicated here with green dots. And the hormonal method columns for
perfect use are indicated here with blue dots. Notice that they’re all very
similar in their effectiveness. So, this statement is
incorrect.
Therefore, the statement that
correctly describes what we see in the provided graph is answer choice (C). Typical use of all hormonal methods
is more effective compared to typical use of barrier methods.
