Ovarian stimulation and monitoring

The next step in the in vitro fertilization (IVF) process is stimulating the ovaries by taking daily injections of hormones. These hormones are regularly produced in your body, however the injections you will be taking contain a higher dose than what would naturally occur. This allows multiple eggs to mature in the ovary, which increases the chance for pregnancy.



Shots of fertility medicine(s) that mimic the body’s natural hormones are given daily. This is done in hopes that 3 or more eggs will develop during the cycle. Most of the time, the more eggs fertilized, the better the chance for pregnancy. Fertility medicines often given are:

  • Follicle Stimulating Hormone (FSH), such as Follistim® and Gonal-F®
  • human Menopausal Gonadotropins (hMG), such as Menopur®
  • hCG (human Chorionic Gonadotropin, chorionic gonadotropin), such as Pregnyl®, Novarel®, or Ovidrel®
  • Leuprolide (leuprolide acetate, Lupron®)
  • Ganirelix Acetate® or Cetrotide® (May be used instead of leuprolide.)

There are multiple stimulation protocols. The care team will decide which is best for you. They will talk with you at your 1st visit. Then they will give you more details at your cycle start visit. 

  • You will take oral contraceptive pills (OCP’s) before starting the shots with some protocols. 
  • You will need a baseline transvaginal ultrasound with all protocols. Then you will need 1 to 4 more ultrasounds, based on your protocol and response to the shots, during your ovarian stimulation. 
  • You will need SQ and IM shots. These will change based on the protocol and how your ovaries respond to the medicines. You may have as few as 8 (our shortest protocol) to 21 or more (our longest protocol) days of SQ shots before oocyte retrieval.

When you have at least 2 retrievable follicles with an average diameter of 18 mm (or larger), you will take a shot(s) in the evening. It must be done 36 hours before oocyte retrieval. It starts the final maturation of the eggs, so they are ready for retrieval. Retrieval must be done before the eggs release (ovulation) from the follicles.


Careful monitoring helps control and optimize ovarian stimulation. Your progress will be monitored with blood hormone monitoring and vaginal ultrasound.

Blood Hormone Monitoring

Blood may or may not be drawn in the morning on several days to follow estradiol (estrogen) levels. This is based on your protocol. 

  • Local labs can be used for this test. The results must be sent by fax to IVF staff by 1 p.m. on the same day the blood is drawn.

Ultrasound Monitoring

During stimulation you will have ultrasounds of your ovaries. 

  • High-frequency sound waves can be bounced off body tissues to show a picture on a monitor. The sound waves cannot be heard or felt. 
  • The pictures show ovarian follicles. Then the care team can see the number, size, and place of the follicles. 
  • While you are lying on your back an ultrasound transducer is placed in the vagina. You will be able to watch the picture of your ovarian follicles on the screen.


Last reviewed: 
November 2021

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