Not much existed in the way of contraception in 1930.
Prehistoric condoms and some crude spermacides were about it. I doubt the topic even came up to anywhere near the extent it does today.
>>>Not much existed in the way of contraception in 1930
Margaret Sanger opened her first birth control clinic in 1916. There was a lot of contraceptive knowledge around at that time, and most of it came from France. Christian churches were aware of contraceptives, and they preached against them.
I’m no expert on the history of contraception, but there’s been abnormal non-procreative forms of copulation since Genesis. People have long used marital sodomy to avoid offspring.