Brief Answer:
Try having sex near ovulation.

Detailed Answer:
Hello,
Thanks for trusting us with your health concern.
It is tough to understand why you are having difficulty in getting pregnant without having your medical history like, menstrual cycle, duration of trying for conception, any previous illness or medication you are on, any genital tract infection and so on.
If your wife has regular cycles of 28 to 30 days, I would assume that she is ovulating periodically and you need to try regularly to have intercourse starting from day 9 till you see maximum slimy stretchable secretions from the vagina which indicates ovulation time. ( This looks like raw egg whites ). Or you can use LH test kits which predicts ovulation. It works similar to urine pregnancy test and you must test your urine daily morning for LH hormone until you detect two lines on the card. And you are most fertile and much likely to conceive when you time intercourse around this period ( next 24 hours ).
Also you may get your thyroid profile tested ( serum TSH and free T4) as it has a role in delaying conception.
If these tips fail to get you pregnant, and if you are trying for more than an year to conceive you may consider getting further evaluation done by your gynaecologist to help you realise your dream.
As you are young, your chances of conceiving is higher than others.
And it helps to know that the chances of spontaneous conception is about 25 to 30% per month per couple at the time if ovulation.

Please feel free to discuss further. I will be glad to answer the follow up queries that you have.
Wishing you good health.
Regards.
Dr. Rakhi Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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