An antinatalist is a supporter of antinatalism - the philosophical position which asserts a negative value judgement towards birth.
Marx's theory is not explicitly pronatalist or antinatalist. Marx focused on economic and social structures in society, rather than directly advocating for or against procreation. However, some interpretations of his work suggest that a society with better living conditions and social support may lead to lower birth rates, which could be seen as leaning towards an antinatalist perspective.
A pronatalist policy encourages couples to have more children, therefore increasing fertility and birth rates (eg. France). However the anti natalist policy attempts to reduce birth rates to decrease the country's population (eg. China)
People adapt to volcanoes by having pronatalist policies as well as antinatalist policies. Some people might think that it is easy to adapt to it but we need to hide as well as to come out but what will happen when we hide and run away too slowly...death. There are already many fatalities already because of the many eruptions from many acive volcanoes.