It's widely reported (at least outside of China) that China's "One Child Policy" caused various forms of parental gender bias in China, such as gender-based abortions, infanticide or adoptions:
The one-child policy had a profound effect on the lives of ordinary Chinese. Notably, in a country where sons had long been favoured in rural communities, a problem of female infanticide swiftly developed after the policy was implemented.
I don't dispute the gender bias exists. But I'm doubtful as to whether the "One Child Policy" caused it, because other countries without the policy also have gender bias, though except for India they don't get reported on much by the media.
Did the "One Child Policy" cause or make worse gender bias by parents?