Commercialization, Altruism, Clinical Practice: Seeking Explanation for Similarities and Differences in Californian and Canadian Gestational Surrogacy Outcomes.

BACKGROUND: Surrogacy is growing worldwide. Although recently some countries have sought to ban it, between 2010 and 2014 the number of babies born to gestational surrogates having in vitro fertilization treatment in California doubled, and in Canada it grew by 35%. This work seeks to fill identified knowledge gaps about the similarities and differences in the practices and outcomes of gestational surrogacy, which in California operates on a commercial basis, whereas in Canada it is illegal to pay a surrogate. The paper focusses on the period from 2010 to 2014, for which comparable American and Canadian national assisted reproduction technology information exist.

STUDY DESIGN: A retrospective data analysis was performed using information on gestational surrogate multiple births obtained from the Centers for Disease Control and Prevention National Assisted Reproductive Technology Surveillance System (NASS) and Canada's Assisted Reproduction Registry-Better Outcomes Registry and Network (CARTR-BORN). Multiple birth rates and transfers of multiple embryos were compared using relative risk analysis. Adherence to voluntary American Society for Reproductive Medicine-Society for Assisted Reproductive Technology and Canadian Fertility and Andrology Society embryo transfer guidelines was modelled.

FINDINGS: Among gestational surrogates, when donor ova embryos obtained from women aged less than 35 years were used, embryo transfer guideline adherence was 42% in California and 48% in Canada.

CONCLUSIONS: Regardless of where on the commercial/noncommercial boundary North American surrogates reside, they are more likely to receive more donor ova embryos per in vitro fertilization transfer than other in vitro fertilization patients. An altruistic desire to assist childless couples and individuals create families along with clinic practices seem to play major roles in treatment decisions privileging the transfer two or more embryos.