Does progesterone need to be administered in the treatments?

Progesterone is a very important hormone in assisted reproduction treatments. Its main functions are to prepare the endometrium for embryo implantation and to support early pregnancy development.

There are several reasons why exogenous progesterone supplementation is necessary during treatments:

Ovarian stimulation medication can affect the body’s natural progesterone production.
Follicular puncture has a negative effect on progesterone production.
In treatments such as egg donation, embryo donation, or frozen embryo transfer, ovarian function is suppressed to prevent interference with endometrial preparation, making progesterone supplementation essential.

How Is Progesterone Administered?

In Spain, progesterone is approved for vaginal, oral, or subcutaneous administration. Vaginal administration is usually the first option, as it allows for a higher concentration of the drug in the endometrium while avoiding systemic side effects.

Subcutaneous progesterone is an alternative for patients with allergies or those suspected of having poor vaginal absorption.

How Long Should Progesterone Be Taken?

In general, progesterone administration begins:

After ovulation in artificial insemination procedures.
After egg retrieval in IVF procedures.
It is continued until weeks 10-12 of pregnancy, when the placenta starts producing it naturally.

However, when in progesterone treatment, follow always the instructions of the fertility specialist.

What Happens If Progesterone Is Not Taken?

Not taking progesterone may reduce the chances of embryo implantation and increase the risk of early bleeding or miscarriage in the first few weeks.

Possible Side Effects of Progesterone:

Taking progesterone may cause following side effects:

Abdominal bloating.
Fatigue or drowsiness.
Increased vaginal discharge (especially with vaginal administration).
In some cases, headaches or breast tenderness.

It is important that any progesterone treatment is monitored by a fertility specialist, who will determine the most appropriate dose and administration route according to each patient’s individual needs.