Impact of Serum P Levels on Pregnancy Outcome in ART

Abstract

Background: The role of mid luteal progesterone (P) levels has gained interest in the last years. Low serum P levels significantly decrease the chances of ongoing pregnancy, mainly in artificial cycles for embryo transfer. Our prospective studies have found that patients with low serum P levels on the day of ET had a significantly lower live birth rate, either when using own or donated oocytes. Aim: To summarize the current evidence about the impact of serum P levels on pregnancy outcome in ART; and the proposed strategies to overcome this situation. To differentiate the PK and PD of the different routes of exogenous P and how this influence on the interpretation of results. Method: Review of the literature. The research leaded by the lecturer will be presented. Results: In artificial cycles, there is a minimum threshold of serum P levels that needs to be reached. Approximately 30% of women show inadequate levels of serum P after receiving the standard dose of vaginal P. Individualization of luteal phase support by routinely measuring P levels, allows to detect which patients need raised P in order to optimise their outcome. Addition of extra doses of P seems to overcome this detrimental effect, ideally associating other routes of P. Conclusion: Low P levels on the day of ET decrease live birth rates. If outcomes are to be optimised, a minimal threshold of serum P values on the day of ET must be reached. Personalization of luteal phase support is advisable to optimize the results.