Branching Out the Babytree: The Effects of Dual Peer Group Membership on Social Support During Pregnancy in Online Communities

Sandwiches from 12:15, Seminar at 12:30

Social support plays an important role in maternal well-being and infant health outcomes. Nowadays, besides the traditional ways of seeking social support from family, friends, or the government, pregnant women can register in the online maternity communities to form peer groups and seek social support from other users. We use data from the world’s largest online maternity community, Babytree, to investigate the effects of dual peer group membership on the supply of social support during the pregnancy of over 30,000 women. We instrument the enrollment of peer groups by the day of users’ estimated due date, which allows a causal interpretation of our results. We find that the enrollment of an additional peer group of the previous month has positive externality on user’ outgoing social support in their default peer group. Channels of knowledge transfer and reciprocity are discussed with suggestive evidence and related policy implications.