Why is progesterone used in fertility treatment?

The progesterone hormone is essential for a healthy pregnancy. In fact, it is also known as the pregnancy hormone. This hormone is needed before and during a pregnancy. Thus, it is often a part of treatments for infertility.

Role of Progesterone before Pregnancy

After ovulation, the ovaries begin producing the progesterone hormone. This helps thicken the uterine lining or endometrium and prepares it to receive a fertilised egg. Progesterone levels are high about 5 days after ovulation. If this lining is not thick enough, the fertilized embryo will not be able to attach itself to the uterus and thus it might result in a miscarriage.

Role of Progesterone during Pregnancy

Once a woman has successfully conceived, the ovaries will continue to produce progesterone. This is a result of the increased levels of human chorionic gonadotropin (hCG) hormone. At this stage, progesterone prevents the onset of a menstrual period. It also helps provide nourishment for the growing fetus.
A pregnant woman produces up to 10 times more progesterone than a woman who is not pregnant. Initially, this hormone is produced by the ovaries but after 8-10 weeks of a pregnancy, the placenta starts producing the progesterone instead.

Progesterone Use in Fertility Treatment

Progesterone is often prescribed to women undergoing IVF or any other form of assisted reproductive technology procedures. This is because the medicines used for these forms of fertility treatment may interfere with the normal progesterone production. So, progesterone supplements are prescribed to regulate the hormone levels.
Women may also be given progesterone supplements if their ovaries cannot produce the required amounts of this hormone or if their follicles have not developed enough to be able to release progesterone.

Forms of Progesterone Supplements

There are different ways in which progesterone may be administered. A doctor's preference for one form of progesterone over another is usually based on their experience. The ideal one for you is the one which is most convenient to administer. These different forms of progesterone include:

Vaginal Gel - This is easy to use and must usually be applied once a day.
Vaginal Suppositories - These must be inserted into the vagina and may be administered 2-3 times a day.
Vaginal Inserts - These may be used to supplement progesterone but cannot be used in cases of progesterone replacement.
Oral Capsules - These capsules may be taken orally.
Injections -Progesterone injections are oil based and are considered the oldest form of administering progesterone. This injection is given in the buttocks and may be quite painful. Now a days, waterbased(aqueous) progesterone injections are also available which are considered less painful.