Brief Answer: Around 25% chance of conception. Detailed Answer: Hi, Welcome to XXXXXXX I have read your query in details & following is my reply. In a normal couple when semen, wife's tubes & ovulation are fine, there is 25-30% chance of conception per cycle (cumulatively 70% in 6 cycles). You may have had ovulation between 36-56 hours after HCG injection OR may be later (Not all ovulation events are detectable on ultrasound & sometimes ovulation can occur late). Considering this fact & hoping positively, you have around 25% chance of pregnancy this cycle. There are few tips to maximize chance of pregnancy (For future cycles if pregnancy doesn't occur this cycle). 1. Avoid taking Inj HCG so early (18*12mm= average size of 15mm). 15mm is not the optimum size to receive inj HCG. 2. In clomiphene induced cycles, we need to consider endometrial thickness along with follicular size. Endometrium needs to be >8-9mm before taking inj HCG. You can weight for endometrium to improve. Follicle is going to rupture even without inj HCG, so no need to be scared if its taking long. 3. Do not restrict intercourse around ovulation. It increases your stress & reduces fertility. Better option is to do it at least 2-3 times per week irrespective of ovulation & if possible daily around ovulation. 4. You need ovulation induction medicine to make follicles. You may need to take it continuously for 5-6 cycles to have good chance of pregnancy. 5. If there is no conception in this cycle, kindly get tubal patency test done(if not already done). Normally we do not advise tubal patency test so early, but because you are needing such costly medicines for ovulation, its better to be absolutely sure that everything is fine before proceeding further. 6. Preferably take treatment from infertility specialist who is conversant with IVF protocols, as those doctors can handle ovarian stimulation with injectable medicines better way. Hope this helps you. Let me know if you have other concerns. Regards.

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