What is a common luteal phase support option after embryo transfer?

• A. Vaginal progesterone (with or without estrogen)
• B. Vitamin C supplementation
• C. Progestin withdrawal
• D. High-dose estrogen alone

Answer: (A)

Luteal phase support after embryo transfer centers on providing progesterone to maintain a receptive, secretory endometrium and sustain early pregnancy. In assisted cycles, the corpus luteum may not supply enough progesterone, so exogenous progesterone is routinely given. Vaginal progesterone is a common choice because it delivers progesterone directly to the uterus, yielding reliable endometrial exposure with good tolerability, and it can be used with estrogen if the protocol requires. The other options don’t provide the necessary luteal support: Vitamin C lacks proven efficacy for this purpose, progestin withdrawal would remove support, and estrogen alone does not maintain the endometrium or early pregnancy without progesterone.