In Vitro Fertilization (IVF)

In vitro fertilization (IVF) is an advanced reproductive treatment which involves a series of steps and procedures to maximize a woman’s chances of conceiving.
 
These include:
  • The administration of medications to stimulate the ovaries to produce multiple, mature eggs simultaneously.
  • Monitoring the growth of the ovarian follicles that contain the eggs with ultrasound exams and blood work.
  • Retrieval of those eggs from the ovaries.
  • Fertilization of the eggs with sperm, which occurs in the In Vitro Fertilization Stamford laboratory.
  • The transfer of embryos into the uterus to achieve a pregnancy.
IVF handout
IVF consent form
 

Egg retrieval

This medical procedure is done in an outpatient setting. It is not considered a surgery and is done under IV sedation.  The collection of eggs is done using a transvaginal ultrasound with a guide wire and a needle. The needle goes through the vaginal wall and into the ovary directly. Since the ovaries are stimulated with multiple follicles, the ovary sits low in the pelvis and is easily accessed through the vagina.
 
IVF Egg Retrieval preoperative instructions
IVF Egg Retrieval postoperative instructions
IVF Egg Retrieval consent form
 

Fertilization

Insemination

Insemination is a method of fertilizing eggs during IVF. It involves placing a concentrated sample of washed sperm on top of each egg in the lab and letting the sperm fertilize the egg on it’s own. Usually, 50-75% of the eggs that are mature should fertilize.

Intracytoplasmic Sperm Injection (ICSI)

This is an alternative way to fertilize eggs during IVF treatment. The embryologist pushes a single normally shaped, living sperm through the egg’s shell to fertilize the egg. This procedure is most often performed for male factor infertility, a prior unsuccessful fertilization with conventional insemination or for unexplained infertility.

 

Embryo transfer

Embryos are customarily transferred back into a woman’s uterus either three or five days after the egg retrieval.

Instructions after Embryo Transfer

Day 3 embryo transfer

Involves placement of embryos inside a woman’s uterus three days after the egg retrieval. Embryos are usually between 4 and 8 cells and are graded by the embryologist based on their appearance. This procedure is typically done under ultrasound guidance to optimize the proper embryo placement.

Day 5 embryo transfer

When the embryo transfer is performed on day 5, an advanced stage embryo called a blastocyst is transferred. The advantage of waiting until day 5 is that fewer embryos can be transferred to achieve a pregnancy thereby decreasing the risk of multiple pregnancy. In other instances, if a couple have genetic screening of their embryos performed on day 3, results will be available by day 5. This ensures that only the genetically normal embryos that have also progressed to the blastocyst stage, are offered at transfer.

Selective or single embryo transfer

As the pregnancy rates continue to improve with advancing techniques in the embryology laboratory, more and more patients are electively choosing to transfera single embryo at a time. This will help to maximize a woman’s chance of conceiving a singleton pregnancy.  

Who are good candidates for a single embryo transfer?

Young women, women who are undergoing their first cycle of IVF, women who have multiple embryos that have reached the blastocyst stage, and women whose embryos are genetically normal after testing.

Genetic testing of embryos

Embryo testing can be performed in couples undergoing in vitro fertilization (IVF) treatment. Embryos are biopsied, or a few cells are removed, routinely when they have reached the blastocyst stage on day 5 or 6 after egg retrieval. At this stage, the embryo consists of at least 150 cells, so removal of several cells is not a burden. Just the fact that the embryo has successfully reached the blastocyst stage suggests that it is more likely to be chromosomally normal.

After the biopsy, embryos are cryopreserved (frozen) while the biopsied cells are tested. Usually, results are available within a week. Then, during a subsequent cycle, genetically normal embryos can be transferred back into the uterus after preparation for pregnancy.

Preimplantation genetic diagnosis (PGD)

PGD is a method of assessing embryos for disease prior to pregnancy. Embryo testing can be used to detect a specific gene disorder that may be inherited from a patient or her partner.  

Diseases such as:

  • Cystic fibrosis
  • Spinal muscular atrophy
  • Sickle cell disease
  • Hemophilia
  • Tay Sach’s disease
  • Fragile X syndrome

are among those that can be identified with PGD. 

PGD is also indicated when a patient or partner carries a balanced translocation. Even if a couple does not have infertility, they may choose to undergo IVF with PGD to avoid the possibility of having a child with a serious medical disease or multiple miscarriages.

Preimplantation genetic screening (PGS) of embryos for aneuploidy

A normal embryo should have two pairs of 23 chromosomes. One copy comes from the egg (mother) and the other copy comes from the sperm (father). Women are born with all the eggs they will ever have at birth and, as they age, genetic errors occur more frequently. This is the most significant reason why fertility declines and why miscarriages increase with advancing female age.  

Aneuploidy screening involves testing each embryo to determine which ones are chromosomally normal. This testing is currently not standard of care. It can be considered for:

  • Couples with recurrent miscarriages (due to genetically abnormal pregnancies)
  • For couples who have had prior unsuccessful IVF treatments despite transferring high quality embryos
  • Or if a couple desires to maximize their chances of a healthy pregnancy through IVF.

Embryo cryopreservation

Freezing of embryos is usually done at the blastocyst stage because embryos have almost 100% survival after freezing and thawing. This is offered when there are extranumerary embryos during an IVF cycle or if a patient is not yet ready to proceed with an embryo transfer. Occasionally, couples electively freeze embryos in order to “bank” them. This means that they are trying to accumulate more embryos in order to proceed with genetic testing of embryos.