From the Research
Estradiol blood levels of 900 pg/ml are not safe for a transferable embryo and should be lowered to minimize the risk of venous thromboembolism and optimize implantation rates. The optimal estradiol range for embryo transfer is typically between 200-600 pg/ml, as levels exceeding 800 pg/ml have been associated with reduced implantation rates and pregnancy outcomes 1. High estradiol levels can affect endometrial receptivity and create a suboptimal environment for embryo implantation. Some key points to consider:
- Estradiol levels above 800 pg/ml may reduce implantation rates and pregnancy outcomes
- High estradiol can affect endometrial receptivity and create a suboptimal environment for embryo implantation
- The goal is to create hormonal conditions that most closely mimic a natural implantation window
- Excessive estradiol can disrupt this balance and increase the risk of venous thromboembolism, as seen in studies such as 2, 3, and 4 If your levels are at 900 pg/ml, your fertility specialist may recommend temporarily reducing or adjusting your estrogen supplementation (such as decreasing Estrace/estradiol tablets or patches) for a few days while continuing to monitor your levels. They might also consider delaying your transfer until hormone levels stabilize in a more favorable range. It is essential to note that the route of administration for estrogen hormone therapy can impact the risk of venous thromboembolism, with transdermal systems potentially having a lower risk compared to oral estrogen-only hormone therapy 4. You should contact your fertility clinic immediately to discuss these levels rather than proceeding with transfer as scheduled.