When the patient’s menstrual cycle has begun, gonadotropin injections are used to stimulate her ovaries to generate more follicles. Sonography and blood tests are used to monitor the growth of the follicles and changes in hormones. Finally, the physician will decide when the follicles are mature and the best time for oocyte retrieval. The total treatment will take a total of 14 to 18 days, depending on each individual patient’s response to medications.
During the first few days of menstrual cycle, the size of the primodial follicles are about 5mm. The follicles are stimulated by follicle stimulation hormone (FSH) and reach a diameter of about 8mm and begin to secrete estrogen. When the follicles become 15mm, they can secrete even more estrogen, and trigger the pituitary to release luteinizing hormone (LH). Medications can be used to suppress the release of LH and prevent premature ovulation in order to continue to collect more follicles. Finally, human chorionic gonadotropin (hCG) or gonadotropin releasing hormone agonist (GnRHa) is used to trigger the finial maturation of the oocyte. Around 36 hours after the trigger shots, transvaginal oocyte retrieval will be arranged.
Oocyte retrieval is performed under the guidance of transvaginal ultrasound. The fluids aspirated from each follicle is sent to the laboratory and the embryologists then transfer the aspirated oocytes to another culture medium.
For the husband’s semen specimen, the embryologists wash and process the sperm, in preparation for the oocyte to be fertilized. After fertilization, embryo culturing is continued for three or five days, resulting in day 3 eight-cell embryos or day 5 blastocysts. Depending on your condition and discussion with you physician, the embryo may be transferred back into the uterus or cryopreserved to be transferred in a following cycle. If the embryo is transferred, progesterone supplement will be given for the implantation of the embryo.