Well, I can tell you that it IS definitely possible to get pregnant and carry to full term after having a tubal ligation.
Here's my story: I had a tubal ligation in January 2005 after my daughter (2nd child) was born. During my pregnancy I decided that since I already had a 5-year-old son and was having a baby girl that time around, one of each was enough for me.
My OB/GYN did my surgery (tied, cut & burned) immediately after delivery. All went well and I healed quickly. Everything seemed a-OK and holding up.
I never was super consistent or strict about tracking my cycle, but I did have a general/round-about idea of when I was supposed to start each month and it always seemed to begin on time.
Well, 2 years went by and it was 2007. I remember that year had started off so insanely busy. It was various things (basically just life in general), one after another for months and months on end, and it was at the beginning of August of that year when I realized that my period was somewhere in the vicinity of 6-8 weeks late.
Once I realized I was THAT late I start panicking ... but at the same time, in the back of my mind I was also telling myself, "No, there's no way I could be pregnant, there has to be something else wrong with me". However, I'm an over-analyzer and a constant worrier so I had so many emotions and thoughts running through my head that I just didn't know what to do with myself.
Quickly the part of me that was in "full-on-freak-out-mode" won out and I went out and bought a pregnancy test. I took the test and when that thing came out positive I just about had a heart attack. The only thing that I could even think to do at that moment was to call my sister. I was crying so hysterically when she answered the phone that she didn't even know what I was trying to say LOL.
Once she calmed me down she suggested that I first call my fiance and tell him what was going on (he was at work) and then to call my OB/GYN immediately after because it was more than likely that it was an ectopic pregnancy.
After talking to my fiance (who also freaked out LOL) I called my doctor's office and spoke to the nurse who told me to come in for blood work within those next few hours.
I went right in and did the blood work and she called me back later that day and asked if it were possible for me to come right back because I needed to have a vaginal ultrasound and be examined. She said my results definitely showed up with the pregnancy hormone and my doctor needed to see where the embryo had implanted itself.
I remember when my doctor walked into the exam room after the ultrasound, she was smiling and the first thing she said was, "Well, you won't need to have surgery because it's not ectopic. The embryo is implanted in your uterus."
... to which I stupidly asked (apparently not thinking straight), "OK, so what does that mean?".
She was like, "Ummm, it means you're having a baby. You're due April 1st."
Anyway ... to slightly shorten an extremely long story ... I gave birth to my third child March 25, 2008 (a son). He is now a happy and healthy 7-year-old
I absolutely knew right from the start that I wanted to have another surgery after his birth. I asked her if I could just have a partial hysterectomy since the previous tubal ligation failed but ... that was a no-go, she wouldn't agree. She said the only other thing she would be willing to do is completely remove my tubes; which would still leave my ovaries and uterus functional, just without the pathway from one to the other ... so I ended up having that surgery 6 weeks after delivery and thankfully it has held up. I love all three of my kiddos to pieces but I, without a doubt, don't want anymore.