1. Difficult to predict your fertile period
2. Natural conception might get delayed
3. Aanemia, Vitamin Deficiency
4. Hormonal imbalance(Thyroid and prolactin)
5. PCOD
6. Very low or very high BMI
7. Physical or mental stress

Treatment

  To treat anemia, hormonal imbalances and PCOD
  Lifestyle modification
  Healthy Dietary Habits
  Ultrasound monitoring of follicular growth and ovulation( release of egg from the ovary)
  Medication for follicular growth and ovulation
  IUI ( intrauterine insemination)

What next if you still do not conceive?
  Check for other causes of infertility like male factor, tubal factor, uterine factor, or any other factor and treat accordingly
  IVF / ICSI