According to Ayurveda and Ayurvedic Treatment for Infertility in Female, there are 4 factors required for conception. Ayurvedic Treatment for Infertility in Male and Female (replace with this title - Treatment:)
Quality menstrual cycle. It should be regular. Should not be clots, pain. There should not be white discharge. Colour must be fresh red. There should not be any smell.
Uterus, fallopian tube, ovary must be healthy. There should not any abnormality like Tubal block, adenomyosis, uterine fibroid, ovarian cyst, chocolate cyst, endometriosis, PCOD/PCOS etc.
Nutrition to uterus. Ayurveda has given the beautiful example. Uterus is like land. If land is fertile then seed can grow easily. But if land is not fertile then there are no chances to grow the tree. Same as uterus should have good nutrition. Endometrium thickness should be 7 to 8mm.
Beej means good quality of ovum. At the time of ovulation intercourse should be perform.