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Hormone Assays A mature follicle produces Estradiol (E 2) approximately 200 pg/ml. E 2 levels in Blood are measured in conjunction with on essentially the same basis and schedule as ultrasound. E 2 levels in the blood indicate the degree of ovarian response to stimulation. As follicles, develop, they secrete increasing amounts of the estrogens. Higher the E 2, greater is the follicular development. Estrogen estimations are certainly required in women at risk for OHSS, adequate follicular growth but inadequate endometrial thickness. Estimate the level of serum E 2 on FSH day 5. If serum E 2 is <700 pmol/l the FSH dose can safely be increased by 75-150 units. If Estradiol is low on day-9 of the cycle, hMG, rLH or hCG is added to the rFSH. FSH is given until the day of hCG administration. 2,000 to 5,000 units of FSH are required.

GnRH antagonist (GnRH-ant) protocols These are used to prevent unexpected premature LH surge. TVS on FSH stimulation day 6; when the largest follicle is > 12 mm irrespective of the cycle day, Orgalutran 0.25 mg (GnRH-ant) is administered for 3 consecutive days. Alternatively 3.0 mg are given as a single dose. GnRH antagonists are used in selected cases where GnRh agonists down regulation have not been used. It can be done without prior pituitary suppression. Pituitary suppression started when premature LH surge is likely to occur. Gonadotrophins dosage is not increased early in the cycle.

Human Chorionic Gonadotrophins (hCG) administration is to prime the eggs before they are retrieved. hCG, which acts like LH is administered when > 3 follicles are > 18 mm and endometrial thickness is > 8 mm. Injection hCG 5,000 to 10,000 units is given and ovum retrieval done 36 hours later. rLH is now available and is being increasingly used instead of hCG.

Ovum Pick (OPU), Egg retrieval (ER) is the Oocyte recovery procedure is a minor surgical procedure that takes about half an hour. It can be performed under short acting intravenous or local anesthesia. Light general anesthesia is usually used for the comfort of the women unless she prefers not to use. It is done 36 hours after hCG injection.

The eggs are collected by TVS-guided oocyte aspiration. This is a simple technique. A fairly small needle is introduced into the follicles through the vaginal wall guided by the ultrasonic probe. If the follicles are well developed, ova are successfully retrieved in > 90% cases.

An adapter fitted vaginal transducer is introduced into the vagina and taken deep to its upper part to locate the ovaries and visualize the follicles in them. An aspiration needle is introduced through the adapter. Ultrasound helps the gynecologist to accurately guide the needle into each follicle which is aspirated into the test tubes.

The aspirate contains the egg in it. These flushing are placed in Petri dishes and immediately examined in the laboratory to determine if eggs (ova) have been retrieved.

If egg is not retrieved from any follicle, the collapsed follicle is re-inflated with a solution of flushing medium which is also re-aspirated to find the ovum. If not found the process is repeated until the follicle is well washed All the follicles are aspirated. Retrieved eggs are placed in Petri dishes containing culture medium & allowed to remain there undisturbed for 2-5 hours.

The woman is prescribed progesterone hormones for luteal support. Progesterone nurtures endometrium to be favorable for implantation of the embryo. These preparations are in 3 forms, intramuscular injections, oral tablets and the vaginal pessaries which can also be used per rectum.

Injections are painful, oral preparations can be influenced by gastric secretions. The most frequently used are progesterone vaginal (rectal) pessaries. In selected cases vaginal gel is used. These are continued for 6-12 weeks if the woman becomes pregnant.

   
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