It all depends on you and your body chemistry/mechanics. Before surgery I was a fertile myrtle.
I got pregnant a year and half after I had surgery, month and a half AFTER I had a panni done...I was on the pill and used a condom and pulled out...yep he is hell bent on getting here...YES i do know when the night I got pregnant...different story different day
After surgery, ANY surgery your body goes through changes. *duh*. With this surgery you are losing fat, and if you have like a Panni down or any other excessive skin taken off your body hormones need to readjust. DURING that time, your body is so use to producing the "excessive" hormones that it takes a couple of months for them to "level" out. SO you will have all that extra hormone in you, with the weightloss it does make you more fertile.
Why I was on birth control in the first place...After I loss a good amount of weight I was getting my period every 15days. So the BC help level it out. Got my period like I did before my surgery. every 28days like clock work. AFTER my Panni, it was a "normal" period in March and when April came around, I got it on April 2, had my period for OVER a week and half. Had to call and cancel papsmear and revisit to get more BC...NO i wasnt out but would be in 2weeks...couple of days later i stopped bleeding and had sex...WHAMO! oh and it shouldve been my "safe time" too...that weekend I got my "period" again and come to find out it was break through bleeding....SOOO yes we are more FERTILE. Think of us being on fertility drugs, without the drugs.
So I guess you could say I used 3forms of BC...lol
ok sorry for rambling....