Resolution 15Sociological forces around the time of WWI led to this Lambeth Conference decision of 1930, approving the use of birth control in hard cases. This is acknowledged by everyone as the decision which reversed the unanimous testimony of the previous two millennia that Scripture strictly prohibits ALL intentionally contraceptive sex. All other churches, including Missouri Synod Lutherans, attacked the Lambeth decision as flatly contrary to Scripture and the unanimous teaching of the church.
The Life and Witness of the Christian Community - Marriage and Sex
Where there is clearly felt moral obligation to limit or avoid parenthood, the method must be decided on Christian principles. The primary and obvious method is complete abstinence from intercourse (as far as may be necessary) in a life of discipline and self-control lived in the power of the Holy Spirit. Nevertheless in those cases where there is such a clearly felt moral obligation to limit or avoid parenthood, and where there is a morally sound reason for avoiding complete abstinence, the Conference agrees that other methods may be used, provided that this is done in the light of the same Christian principles. The Conference records its strong condemnation of the use of any methods of conception control from motives of selfishness, luxury, or mere convenience.
Voting: For 193; Against 67.
However, it only took a matter of a few short decades for the continuing social and political forces to cause all of Christendom to capitulate. In 1959, the unofficial change in teaching in the LCMS was marked by the publication by CPH of Alfred M. Rehwinkel's book Planned Parenthood, praising Margaret Sanger. The "hard case" arguments were very much a part of this.
Even the Roman Catholic Church finally gave in to the primary argument of the Lambeth decision of 1930. Paul VI's Humanae Vitae accepted the false dichotomy of the "hard case exception", but nuanced the RC solution by forbidding "artificial" means while officially allowing the most effective "natural" means of having sex while preventing conception, NFP.
The problems with the Lambeth decision are many, but one proved particularly insidious. That is, if contraception is okay in some hard case scenarios, then who gets to decide when it is okay to contracept? Where is the line and who is the one drawing it? How are couples to be counseled? Here is where the rubber hit the road. Children became a choice and people needed a framework to make that choice in.
A supposed "right to privacy" came to the rescue. This "right to privacy" is the very argument that was used to abolish the Comstock laws, legalizing birth control. Ultimately, everyone became subject to his own devices.
The belief that having children is a choice, and that people have a right to privacy, then led quickly and inevitably to the legalization of abortion. This entire series of change took only 43 years from the Lambeth decision until the legalization of abortion in 1973.