With that being said...here goes...
The month before Josh and I were married, I scheduled an appointment with my family physician so he could meet with me and prescribe a birth control method that I thought would work for me. At that point, I was not fully aware of all the options, and I didn't give it much thought. I was really only familiar with the pill, and that's what I asked him to prescribe to me. There wasn't much said at this appointment, I really just wanted the prescription and then I'd be on my way out the door! I already had my yearly exam, so I was good to go.
At some point I remember my cousin Leslie asking me if I had given Natural Family Planning (NFP) any thought. She discussed it with me and didn't come across as pushy at all. I wasn't really interested in it at the time because I guess I just thought everyone used the pill. Even notable Christian authors and radio talk-show hosts weren't against it.
My upbringing - both at home and at church - did not give me any indication that there was anything wrong with chemical birth control methods. So between the years of 2001 - 2003, I took the pill until we decided we'd like to start "trying" to have a baby. I conceived within a month of going off of it.
I then went back on the pill after I had Caleb until the fall of 2005 when we decided to start "trying" to have another. I conceived again within a month of going off of it. And I used the term "trying" loosely. We just weren't preventing.
Then after having Sarah...for some reason...I just felt like I shouldn't go back on it at all. I just started thinking about how it works, even though I actually had no idea how it worked. I don't like being ignorant about something, especially something that effects my body, so I realized I needed to be more aware of what I was doing. So I started researching.
I had no idea there were so many books and other material pertaining to this subject.
Here is one of the first things I read that made my heart sink:
According to multiple references throughout The Physician's Desk Reference, which articulate the research findings of all the birth control pill manufacturers, there are not one but three mechanisms of birth control pills:
1. inhibiting ovulation (the primary mechanism),
2. thickening the cervical mucus, thereby making it more difficult for sperm to travel to the egg, and
3. thinning and shriveling the lining of the uterus to the point that it is unable or less able to facilitate the implantation of the newly fertilized egg.The first two mechanisms are contraceptive. The third is abortive. 
Abortive? How could that be? Why was I never told that? Is it just because I didn't ask, "Will I be ending a potential pregnancy if I take this?"
Then I started wondering about other forms of birth control. What about an IUD? Well, that wasn't any different:
Some forms of contraception, specifically the intrauterine device (IUD), Norplant, and certain low-dose oral contraceptives, often do not prevent conception but prevent implantation of an already fertilized ovum. The result is an early abortion, the killing of an already conceived individual. Tragically, many women are not told this by their physicians, and therefore do not make an informed choice about which contraceptive to use. 
Even if you go to the Mirena's website and click on FAQ's - How does Mirena work? it says "Makes the lining in your uterus thin"...do women realize what that means? It means an already fertilized egg cannot implant.
But if we as women are convinced that we're just not creating life, we keep using these chemical birth control methods. The fact of the matter is, however, that many times we MAY HAVE created life and didn't now it. What a devastating thought.
There is so much information out there about this. We need to be informed.
And I just want to make it clear that I did ask a local OB/GYN about this...here is part of the email response I received:
"It all depends on if you consider a fertilized egg which hasn’t implanted, (therefore not producing any hormones/preg test for mom) is really a and thus an abortion or not. Fertilized eggs that don’t implant very likely happen quite frequently with God/Mother Nature in charge, we don’t know because until they implant, there is no way we can know."
And since I do believe that a fertilized egg is life, because I believe that life begins at conception (defined as the fusion of gametes -egg and sperm - to produce a new organism) then I believe that these chemical options are not options for me.
Of course there are methods to prevent pregnancy that are non-chemical. NFP, male or female condoms, diaphragm, cervical cap, or sterilization. For some, none of the "barrier" methods I mentioned are ok and neither is sterilization. I wrestle with this often.
There. I did it. I wrote about a topic that just might be as difficult to discuss as my Santa post! But in all honesty, I pray that you will seek out the information that you need to BE SURE about this topic.
This blogger has some amazing insight. Thanks, Mrs. Haid, for sending me her page.
*Edit* Because someone asked me a question in the comment section, I wanted to include my answer here:
From what I have read, the three you mention [The Patch, The Nuva Ring, and The Shot] list the same "mechanisms" as I listed for the birth control pill. They have have a "last line of defense" of keeping the uterus thin, therefore preventing a fertilized egg from implanting. I do not believe that any chemical birth control 100% of the time keeps an egg and sperm from meeting.
Randy Alcorn, Prolife Answers to ProChoice Arguments (Multnomah Publishers: Sisters, OR: 1992, 1994)