The eggs in a female’s ovary are formed in fetal life (when she was in her mother’s womb) No new eggs are formed during the life span of a woman. The available eggs in the ovary mature and ovulate in each cycle till menopause.
Ovarian reserve is a measure of the number of eggs remaining in the ovary, capable of fertilization and resulting in a pregnancy. When the number of eggs in the ovary are few, it is labelled ‘diminished ovarian reserve’
Aging is the most common cause of diminished ovarian reserve. A woman in her 20s has the maximum chance of conception (12% in each cycle) as the quality and quantity of eggs are good. With aging, there is a gradual decline in the quality and quantity of eggs. A woman at 40 years has a 5% chance of getting pregnant in each cycle.
Some women may have diminished ovarian reserve at a younger age. They may be born with fewer number of eggs or have rapid depletion of eggs due to the presence of antiovarian or antifollicular antibodies. This is usually associated with other immunological conditions in the woman.
Surgery in the pelvic region,oophorectomy(removal of ovaries, endometriosis, Chemotherapy, Radiation are other causes of diminished ovarian reserve.
It is possible for a woman to get pregnant naturally at this age, though the chances are low due to diminished egg number and quality. If planning for a pregnancy after 40 years, it is wiser to consult a fertility specialist at the earliest and get yourself and your partner investigated at the earliest.
Some women may have no symptoms due to this condition. Usually women with diminished ovarian reserve have shorter menstrual cycles i.e between 24-28 days cycle. This happens as the follicles tend to grow and ovulate faster in the cycle.
However, if you are <35 years age and trying for pregnancy for >1 year or of higher age and trying for pregnancy for >6months, get your ovarian reserve tested.
Your doctor takes a detailed menstrual history and past medical/ surgical history. If you have had a previous ovarian stimulation / IVF cycle, < 5eggs retrieved is an indication of poor ovarian response which may be due to diminished ovarian reserve.
Blood tests on day 2 of cycle with high FSH values, low AMH values is indicative of diminished ovarian reserve.
Ultrasound scan of ovaries show a low antral follicle count (<5-7) which is the total number of follicles 2-9mm in diameter during a day 2 menstrual cycle scan.
Studies have shown that natural pregnancy is possible with diminished ovarian reserve, provided all other fertility parameters such as regular ovulation, semen analysis, fallopian tube patency and normal uterus is normal. This is measure of the quantity of egg and not quality.
Younger women <30 years with diminished ovarian reserve have better chances of conception compared to older women.
A few adjuvants such as DHEA , androgens have been proven to be of marginal benefit is improving the number of eggs retrieved in IVF cycles and chances of pregnancy. Well controlled studies are unavailable.
Planning pregnancy at the earliest or freezing embryos/ oocytes as part of fertility preservation can be offered to patients unwilling for pregnancy at the earliest.
If a woman with diminished ovarian reserve is planning IVF, the best IVF protocol is decided based on age, previous treatment history and quality of embryos in past cycles, if available. Pooling of embryos from 2-3 cycles, prior to embryo transfer is recommended in women with diminished ovarian reserve to provide best pregnancy rate.