Tamil Nadu Pregnancy and Heart Disease Registry (TNPHDR): design and methodology oleh Justin Paul Gnanaraj, S Anne Princy, Karen Sliwa-Hahnle, Sowmya Sathyendra, Nambirajan Jeyabalan, Ragothaman Sethumadhavan, Selvarani G, N. Sumathi, Vinotha S, Pachaiappan P, Vimali Murali, Shanthirani B, Gomathi T, Muthuprabha P, Panniyammakal Jeemon, E. Elavarasi, Rajarajeshwari R, Vijaya S, Kanmani K, the TNPHDR investigators