Most modern methods of NFP rely, to a greater or lesser extent, on an understanding of the patterns of cervical mucus that every fertile woman experiences. This is simple enough in theory, but in practice the fact that each woman is a unique individual means that her patterns of fertility will be unique as well. With competent instruction virtually every woman can become familiar with her own, particular patterns, but what is infertile for me may be potentially very fertile for my neighbor, my best friend or even my sister. This makes it difficult to write books or websites that allow a woman who has anything other than perfectly regular, typical cycles to teach herself. There are just too many variations of "normal" and too many ways to misunderstand or misinterpret for me to recommend self-teaching to be a good way to learn NFP (and this is even more true for breastfeeding moms who can go through a number of different infertile patterns - patterns that are different than at any other time in her life - before fertility finally returns). Fortunately, even women who do not have the blessing of a local NFP teacher (or babysitting) are able to learn NFP with the help of teachers who have seen many, many charts and so know from experience how to pick out those all important patterns through WOOMB International's internet teaching service or with the CCL's home study kit (which include sending early charts to certified teachers for review)*.
2. NFP cannot "pinpoint" ovulation.
NFP allows couples to tell the difference between days that are definitely infertile and days that are potentially fertile. Usually it is also possible, in retrospect, to narrow the time during which ovulation could have occurred to about three days. But, without daily ultrasounds of the ovaries, it simply is not possible to identify the exact day on which ovulation occurs.** It is also quite common (again, particularly for breastfeeding moms) to have occassions where it isn't clear whether or not ovulation occurred at all. And all of this uncertainty is absolutely fine. The purpose of NFP is to allow couples who need to avoid pregnancy to identify days on which they can be confident that intercourse will not result in conception and to allow couples who would like to achieve pregnancy to identify the days on which they are most likely to succeed and it is not necessary to know the exact day of ovulation for either of these purposes.
3. There is no one for whom NFP is physiologically impossible.
Because I write about NFP online and make my email address available at the bottom of my columns I not infrequently receive emails that go something like this, "I understand what the Church teaches and would really like to use NFP, but I absolutely must avoid pregnancy and even my NFP teacher says my charts don't make any sense." My response is always to ask the person to send me a few months worth of charts so that I can take a look and see if I agree that NFP really is impossible for this particular couple. As a result I have seen charts from women with all sorts of complicating factors - psychiatric medication, medication for breast cancer, seizure medication, medication for thyroid disorders, chronic yeast infections, physical abnormalities of the uterus and cervix and lots and lots from women who simply have very long or very irregular cycles for no apparent reason - but I have never seeen a chart which made it truly impossible to use NFP.
Occasionally it is possible to identify only a week or so of clearly infertile days each cycle. Once in a while there may be a month or six weeks during which it is not possible to determine whether the woman is fertile or infertile (once again, this is very often the case just before the return of regular cycles during breastfeeding). Sometimes it is not clear whether the woman is ovulating regularly or even if she is ovulating at all. But I have never seen a chart where, after a few months of charting, there were not at least some days each cycle on which the couple could be confident that they would not conceive.
Couples who believe (or have been told) that NFP won't work for them need to look hard for a better teacher. Call the head office for the method of NFP you were taught and tell the person who answers the phone that your NFP teacher told you that NFP was impossible for you and you would like someone else to take a look at your charts and give you a second opinion.
4. Even perfectly regular cycles, aren't.
Most women find that the length of their cycles varies by 3 or 4 or 5 days from month to month, but even women whose cycles are always exactly the same number of days will find that the timing of events within the cycles varies by a few days. The human body is not a machine and one of the most common errors in the use of NFP is making assumptions like, 'It's so early in the cycle I can't possibly be fertile yet' or 'It's so late in the cycle I must have already ovulated'. Each new cycle has the potential to be considerably longer or shorter than any that came before it and predictions about when fertility will occur simply cannot be relied upon.
5. It's OK not to like it.
NFP can be a tremendous blessing for a couple who must avoid pregnancy, but it is also a privation and most couples who seriously use NFP to avoid pregnancy for any length of time will feel this. God does faithfully supply the graces necessary to cooperate with Him and NFP is not impossibly burdensome when it is truly necessary, but it usually isn't fun or effortless either. NFP is not an easy way out of the struggles and sacrifices of bearing and raising children because it may entail significant struggles and sacrifices of it's own. So it is OK not to be happy about using NFP. It is OK to be angry or sad that it is necessary. And many of us must grow considerably before we can regret only that it is necessary to avoid pregnancy and not to hang on to feelings that if we could only legitimately use contraception life would be better. But even when we use NFP only out of obedience (even grudging obedience) God is so very generous with His grace and blessings and grow and flourish we will.
** Even fertility monitors and ovulation predictor kits identify only a time period during which ovulation will probably occur - not the day on which it definitely occurs.
Copyright 2009 Sara Fox Peterson
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