what is size of follicle which helps in pregnency?

Hi,
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The follicle size should be about 20mm to be able to rupture and release the egg. You can consider getting follicular scan done to monitor egg follicle growth and prediction of ovulation to help you time intercourse for fruitful results. If you have been trying for pregnancy and have not been successful, you should consider getting a complete infertility work-up done for you and your partner to see if there are any underlying causes for the infertility/inability to conceive. Treatment as appropriate (based on examination and investigations results) would be started to help you get pregnant. Consider visiting your gynecologist/obstetrician for further evaluation and assistance and be in regular follow-up and monitoring as instructed. Have diet with foods rich in zinc content to ensure better maturation of egg and sperms. Monitor cervical mucus changes and the BBT (basal body temperature) charting to predict your ovulation and time your intercourse for having fruitful results. Have intercourse in positions that allow for deeper penetration for high deposit of semen.
Take care.