Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.stat.math.independent

Topic: Please comment on the following statistical calculation for the risk of pregnancy
Replies: 1   Last Post: Aug 16, 2013 1:19 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Jeff Jefferson

Posts: 1
Registered: 8/15/13
Please comment on the following statistical calculation for the risk of pregnancy
Posted: Aug 15, 2013 5:50 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

Hi, the risk of pregnancy on the condom is 1 in 50 in perfect use, and 1 in.
6.7 in typical use. This is the yearly risk assuming 80-100 sex acts. The
risk of pregnancy on hormonal birth control pills is 1 in 333 in perfect
use, and 1 in 12.5 in typical use, again assuming 80-100 sex acts. If
combining the two types of birth control would the yearly risk be 1 in 6.7
times 1 in 12.5 = 1 in 83.75 in typical, and 1 in 50 times 1 in 333 = 1 in
16,650 in perfect, or would the yearly risk be 100 times safer than that.
For instance the per act risk on the condom must be 1 in 5,000 in perfect
and 1 in 670 in typical, times 100 acts to equal 1 in 50 and 1 in 6.7, and
likewise the per act risk on hormonal birth control pills must be 1 in
33,300 in perfect and 1 in 1,250 in typical, times 100 acts to equal 1 in
333 and 1 in 12.5. Therefore would you not multiply the two per act risks
times each other, for 5,000 times 33,300 = 166,500,000 combined perfect per
act, and 670 times 1,250 = 837,500 combined typical per act, then times 100
sex acts, and therefore bringing the yearly risk of pregnancy of using both
condoms and hormonal birth control pills, together, down to 1 in 1,665,000
in perfect use, and 1 in 8,375 in typical use.






Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.