I was hoping you fertility experts out there could shed some light on how I got pregnant when I was TTA, so that it doesn't happen again! I'm going to give you all the info I can think of that might affect fertility, so bear with me.
After DD was born, we breastfed more or less exclusively (nursing every 2-3 hours around the clock plus some pumping just to have a store of extra milk on hand, occassional bottle of expressed milk if I had to leave her for some reason). Around 4 mo, I reluctantly went on the minipill, as I didn't know anything about FAM/NFP and everyone was telling me that bf didn't work at all for bc. After only 1 mo of the minipill, I got the Shot because I was on an extended stay in Mexico and couldn't get the minipill. Soon after getting the Shot my milk dried up, but I did everything I could to get my milk back. After about 6 weeks I no longer needed to supplement because I was able to increase my supply through intensive nursing, pumping, and use of galactalogues. After this experience, I swore off hormonal bc. I introduced solids at 6mo but DD didn't take to them until after about 8mo. At about 7mo I started sub teaching a few hours a week. DD reverse cycled but I still pumped every 3 or 4 hours during the day. At 9mo went back to exclusive nursing with no pumping as I was no longer subbing and was home all day. At this age she was still very dependent on nursing. So there's the bf info.
About the same time I was having problems with the Shot I started getting more involved with the Catholic Church and discovered FAM/NFP. I decided to give it a go, as I never felt comfortable using artificial bc. I started charting at about 9.5 mo pp. My temps were all over the place, I'm guessing because of DD's nursing schedule at night. I monitored CM but was dry, dry, dry. Right after starting to chart I had a single day of slightly brown mucus. We abstained for several days afterwards, just in case. In fact, we did a lot of abstaining, just because I was paranoid I was missing something. At about 10.5 mo pp, I had an upward temp shift and it just stayed up there. I'm guessing this was because I was pregnant. I never had PPAF, unless you count that one day of barely-there, barely-brown mucus.
So there you have it! No noticible CM (I did both internal and external monitoring), no recognizable temp pattern, no AF, lots of abstinence...where did I miss the return-to-fertilility red flags?
Wife to DH from Mexico, and mother to DD (01/10); DS (09/11); and one on the way (03 or 04/14)
My guess would be that the brown mucous was O spotting. You said you started abstaining when you saw this, but how soon before the brown CM did you BD?
I think it would be easier to use FAM to prevent, after your PPAF....just because that first egg can be elusive and temps can be erratic. I also hate hormonal BC; we were using condoms before TTC this time. After #2, the plan for us would be to use condoms until I got to know my cycle PP and then use FAM to prevent.
ETA: I guess I miss-read, your brown spotting was 1 month before your high temps? My opinion would still stand, however, that you didn't notice any signs because your body was still a little haywire, recovering from birth and preparing for the return of fertility.
Laura (26) DH (39), DS (Jan 2008)
#2 due in Dec 2012 2/12 8/11
I can see several things that may have contributed, but it is hard to be sure.
What I think is most likely is the fact that you were on hormonal birth control. The shot is supposed to be over 99% effective for about 4 months. This means that if you took it at about 5 months PP, it would be 99% effective until 9 months PP. After that, its effectiveness would wane, but it will still have an effect on your system. There may not be enough hormones in your body to keep you from ovulating, but it would have other effects on your body. Progesterone (the active ingredient in the shot) causes cervical mucus to thicken and dry up. It could have very easily blurred your fertility signs. When learning NFP while coming off of the shot, the recommendation is to abstain until you have clear signs of ovulation and to not rely on CM right away. I think that it is very likely that your fertility signs were obscured by the hormones in your system from the shot, and you could not tell that you were going to ovulate because of that.
A second factor is the fact that you were just learning the method. You can read and hear all about how to chart, but most people's first charts still look a little awkward as they learn to read their body's signs. You seem to be rather confident that you were absolutely dry, and I'm not doubting that. It's just more difficult to learn NFP and figure out what is going on when you are in a situation where you are not ovulating. When learning NFP, the normal recommendation is to abstain for one cycle (CM only methods) or at least until confirmed ovulation (STM) so that you can see without interference what your body does while it is preparing to ovulate. Not having a chance previously to observe your pre-ovulation pattern puts you at a greater risk, though many women have learned NFP while in breastfeeding amenorrhea and have successfully CTA'ed during the return of their fertility.
Finally, NFP has been tested to be highly effective (about as effective as the pill) for women who are not breastfeeding and not going through menopause. While many women use NFP quite successfully through their return to fertility while breastfeeding, the effectiveness has not been quite as well established. Still, most unplanned pregnancies that occur during breastfeeding are user error just because of the great amount of abstinence required to follow all the rules carefully when you are not ovulating regularly. Marquette is attempting to study the effectiveness of their method using the clearblue fertility monitor during this time, and they appear to be having good success, but the other methods have not been studied well enough to be rated for effectiveness.
Yes, when your temperature rose and stayed up, that is when you got pregnant. You can assume that you ovulated on or around the last day before your temperature started to rise. Count yourself to be 2 weeks gestation at that point, and you can figure out your due date 38 weeks after that day. Alternately, you can take your first day of temperature rise minus 7 days, plus 9 months to get a due date by the Prem Rule.
I really think that your biggest problem was the long-term hormonal birth control that was still in your system. It is highly likely that if you try to use NFP again after this child's birth, you could do so effectively without the added complication of synthetic hormones in your system. I can understand how you would be concerned, though, given your experience. You may wish to look into the Marquette Method, though the urine sticks for the fertility monitor are not reusable and can get expensive. Good luck to you in finding something that works.