Challenges in cardiology research in pregnancy

Research in pregnancy is challenging as it involves a special 'vulnerable' group due to the involvement of the mother and the fetus. These challenges, which are inherent in studying pregnancy in physiologic and pathologic states, have contributed to the scant research in pregnancy. Until recently, most studies in pregnancy were nonrandomized and retrospective in nature, representing prevailing clinical standards of practice and clinicians' biases. Prospective studies were generally limited to single centers, comprising of small sample sizes and were observational in nature, rather than randomized studies involving therapy. Ethical and legal factors, research mandates, patient factors, the protracted nature of pregnancy, institutional commitment to research, interdisciplinary clinical and research collaboration, funding support, administrative issues and the level of involvement of national cardiac and obstetric and gynecological societies have been barriers to research in pregnancy in developed countries. Even prospective observational studies are difficult to perform due the difficulties involved with obtaining consent, study recruitment and follow-up. Misconceptions regarding research have led to a lack of participation by women. The longitudinal nature of prospective studies in pregnancy, the problems associated with enrolling women before pregnancy and in the first trimester and the failure to understand the commitment required by the patient, as well as many social factors, have led to increased drop-out rates during pregnancy, as well as difficulty with follow-up in the post-partum state. These factors, along with the failure to supplement funding support due to longer study periods than anticipated, have led to studies of small sample sizes. Understanding patient factors that lead to a lack of participation in research or dropping out following initial consent could help make research participation more conducive for pregnant women. The involvement of national societies in the planning and funding of multicenter studies, interdepartmental and interinstitutional collaboration, institutional and extramural funding support and patient incentives are crucial for shortening study duration and ensuring adequacy of sample sizes for successful research in pregnancy. National health service structures, such as those found in Europe and Canada, makes multicenter collaboration for prospective studies more feasible than for countries such as the USA, in which the fees-for-service system is used. Utilization of telemedicine and handheld ultrasound systems and participation in prospective multicenter registries could not only improve the clinical care of pregnant women in underdeveloped countries, but also provide a platform for research during pregnancy. Multicenter and even global registries supported by European cardiac societies have been formed recently that are beginning to bring forth much-needed data regarding pathological states, such as peripartum cardiomyopathy and pregnancy in congenital heart disease. Such studies are largely confined to non-US countries and have started seeing participation from underdeveloped countries. Studies on pregnancy in connective tissue disorders, older women, post-chemoradiation therapy or organ transplantation and in the HIV state remain limited.