Fertility age – Age is the single most important factor affecting female fertility and her chances of having a child. Women are born with all the eggs they will ever have, as she ages her eggs age with her diminishing in quantity and quality fertility and fecundity decreases with increasing age.

Statistical figures about female, age and fertility

Starting at about age 32, a woman’s chances of conceiving decreases gradually but significantly.

  • From age 35, fertility chances taken by half.
  • At 30, chances of conceiving per month is about 20% which declined to about 5% by the age of 40.

Infertility treatment cannot fully compensate for decline in fertility by age. Women undergoing IVF using their own eggs demonstrate that the drop in IVF success is also dramatic. For women under 35 years, the percentage of successful IVF cycles is 41%, for women 35-37 years was 31.9%, between 38-40 years was 22.1%, 12.4% for woman 41-42years, 5% for women 42-44 years and just 1% for women over 44%. That means, after 35 years, IVF birth declined about 10% every 2 years reflecting on similar relationship between fertility and age as we see in natural fertility.

Ovarian reserve and age

Ovarian reserve declines with age. Women normally born with 1-2 million potential eggs (ovarian follicles). Ovarian reserve is like a “bank” that does not take deposits and we are constantly withdrawing from it with each passing month. At puberty – there will be around 1 million eggs which decline to 3,00,000 by 25 years and as the women reaches 35 years the decline starts to get steeper until menopause.

Assessment of ovarian reserve

  • Antral follicle count – by ultrasound to count number of visible follicles.
  • Antimullerian hormone
  • Protein secreted by granulose cells of the preantral and antral follicles.
  • Estimate the total number of follicles inside the ovary.
  • Value remain stable throughout the cycle.

Depending on the age, the values will be higher or lower.

Miscarriage and age factor

As the women gets older the incidence of chromosomally abnormal eggs increases dramatically. The mecoha spindle is a critical component of eggs that is involved in organising the chromosome pair so that proper dunsion of pairs occurs as the egg is developing. The older eggs have significantly more abnormal spindles redisposing to development of chromosomally abnormal eggs. Dneuploid eggs and embryos are responsible for most of the decline in fertility with female aging and for the low pregnancy success rates with IVF and increased miscarriages for women over 40 years of age. The real issue is egg quantity and quality which translates into embryo quality after fertihydration. It is high time that the couples be made aware that medical science still cannot undo the effects of aging.