The Billings Method != "rhythm method". And there are other similar methods that belong to the modern NFP family, grounded in well-researched medical science and backed by clinical trials.
Oh it is "natural", right, because the Catholic Church requires only "natural" remedies for things?
I use quotes since I don't even agree that Billings Method is any more natural than a condom or the pill.
It simply takes more freedom away from the woman to choose when and how she has sex.
Birth Control and NFP: What's the Difference?
http://www.priestsforlife.org/library/4741-birth-control-and...
"NFP is not just a 'method' based on physiology. Rather, NFP is based on virtue. It is based on sexual self-control, which is necessary for a healthy marriage. There are times in any marriage when spouses have to put aside their desire for sex because of sickness, fatigue, travel, or other reasons. In a healthy marriage, love is shown in many ways, and not all these ways of showing love are physical. In fact, to refrain from sex when necessary is itself an act of love. Why? Because in effect the spouses then say to each other, 'I did not marry you just for sexual pleasure. I married you because I love you. You are a person, not an object. When I have sex with you, it is because I freely choose to show you my love, not because I need to satisfy an urge.' Using NFP requires abstinence from intercourse during the fertile days if a pregnancy has to be avoided. This actually can strengthen the couple's sexual life. When the spouses know that they can abstain for good reasons, they also come to trust each other more, and avoid the risk of treating each other primarily as objects of sexual pleasure rather than persons. Artificial birth control, on the other hand, gives free reign to the temptation to make pleasure the dominant element, rather than virtue. It encourages couples to think that sexual self-control is not necessary. It can encourage them to become slaves to pleasure."
I was raised Catholic. The way sex is viewed, and the idea of Mary being a virgin until death (somehow ignoring Jesus having multiple brothers and sisters...) being added hundreds of years later and requiring celibacy shows a very odd obsession with sex.
Not to mention the known history of purposely inventing rules to benefit the Church. Priests children before they were no longer allowed to marry and have sex became Church property.
Regarding comments, my wife and I practice the 'alternative method' and speaking from EXPERIENCE, IT IS EFFECTIVE. In fact, if you look at the numbers, it's more effective than IVF for achieving and 99% effective in preventing. Like all things, you have to understand what you're doing. Also, it is not from the 'word of a celibate man' but is from years of medical research. Here is one (http://naprotechnology.com/).
So many of us are so quick to eat genetically engineered food or take contraceptives that may increase our risk of cancer (source:http://www.cancer.gov/cancertopics/factsheet/Risk/oral-contr...) but we aren't interested in a safe approach, which also is (and more importantly) falls into God's plan. If you read Humane Vitae or other church documents on the subject, it makes perfect sense. No really, just read it. It's a short read. http://www.vatican.va/holy_father/paul_vi/encyclicals/docume...
The church does not have an obsession with sex. Rather, mankind has the obsession with sex and the church is trying to help us understand it's proper place. Since contraception has been widely adopted in the US, divorce, STDs, rape and illegitimate children has sky rocketted. Very unfortunate, but predicted in the 1960s in Humanae Vitae.