can occur only one day of cycle that is ovulation day so unprotected sex around that day only important. As only one day in month nature should be given 12-24 trials (12 to 24 months) before couple need any active management by Gynecologist or infertility
Nothing special in food usual balanced diet
with all vitamins, minerals, protein, omega-3, fibre. Supplements like Folic acid and DHA required and some vaccinations so meet Gynecologist.