The Pill is one of the main contraceptives used in the western world, it has been used for almost 40 years and has been extremely successful in delaying pregnancy. We have managed to get more evidence about the long term and short term aspect of the Pill on the ovarian reserve.
The ovarian reserve is the sum total of eggs which are present in the ovary and which can be recruited. It is a test that looks at numbers, and the anti-Mullerian hormone is one of the tests that can give us an idea of the number of small eggs that are left in the ovary. In a study which was published in Gynaecology magazine in 2015, it looked at the effect of long term hormonal contraception. For almost a year 145 women were seen, those were on the oral contraceptive Pill, the oestrogen and progesterone combined, for a mean period of around 11 years. AMH was collected after a year of stopping the Pill. What it did show was that 44 women had never used the oral contraceptive Pill, and when they had a look at it after a year, there was no difference between the ovarian reserve of those who were on the Pill for a long period and those who were not on the Pill for a long period or not taking the Pill at all.
This gives us a much better idea; it tells us that after a year of being Pill free, there is no difference between the number of follicles which have been generated and can be measured in an ovary which was exposed to the Pill for a long time and that which has not been exposed to the Pill. Also it tells us that the Pill is not protective; it does not protect the ovarian reserve and it does not improve the chance of pregnancy once you have been off it. Age tends to be the most important factor that looks at success, and thus with an advancing age, the quality of eggs also tends to go down.