Brief Answer:
Irregular menses seems to be the problem

Detailed Answer:
Hi XXXX,
I have understood your problem.
For last 4 cycles your menses are not appearing regularly. It is most likely that irregular menses could be the problem. Due to non formation of the eggs, you may not be getting your menses regularly.
However, you are very young, just 20 years of age. It is just for 3 months you are trying to conceive and have failed. We usually lable the case of difficult fertility after one year's failure at your age.
Now I am putting few options for your consideration:
1. Wait for 9 months more, try sincerely with regular intercorse practice. Still if you do not become pregnant, you may start investigating for infertility. Usually the egg release takes place 14 days prior to next expected menses. If you can plan your intercourse accordingly, it may help. However, the problem is that for last 4 months you are having iregular menses. So it may be difficult for you to calculate this day.
2. Initially, get simple investigations done. These will include husband's semen examination, your egg formation evidences by ultrasonography. Even maintaining a basal body temperature chart helps in detecting egg release evidence and day. For this you have measure your body temperature the mooment you get up from your sleep by putting the thermometer under the tongue for 5 minutes. Usually after menses, daily the tempetrature rises gradually. Just at the time of the egg release, there is a fall in temperature by half a degree and next day it rises by one degree. If you are forming eggs, then accordingly you can adjust your intercorse calender. Considering your irregular menses, you may get the FSH, LH blood levels estimated on 2nd day of the menses. You need not go for invasive investigations like laparoscopy or histosalpingography at this stage and get them done later on. if needed.
3. Get complete work up of infertility investigations done on both of you.

I would like to know following information from you:
1. What is your weight? What is your height? What is your BMI? Have you put on weight after marriage or in recent past?
2. When you get delayed menses, do you get heavy bleeding?
3. Do you have thick hair growth on shin, abdomen, chest or face?
This information will help me to suspect or not PCOS in you.
4. Have you undergone any investigations? If so please upload the reports for my review.
5. Also whatever investigations I have suggested or your gynaecologist suggests, please upload their reports.
6. Do you have frequent marital physical relations? What is the frequency?
Please remember, stress and depression worsens the chances for egg formation and pregnancy. So please be cheerful and positive. You are very young girl and just married. With adequately frequent marital physical relations and some intervention if at all required, you have good chance to get showered with the Motherhood.
Please keep in touch with me with all the reports and any more information to share.

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