Overview

In vitro fertilisation (IVF) is a set of assisted reproductive techniques in which an egg and sperm are brought together in a laboratory dish so that fertilisation can occur outside the uterus. IVF is used to help people conceive when natural conception is difficult or impossible, and it is also applied in situations such as single parenthood, same-sex parenting and to reduce inherited disease risk through embryo testing. For background on laboratory fertilisation techniques see further resources on laboratory fertilisation and on fertility care see information about infertility and treatment options.

Procedure

The standard IVF pathway involves controlled ovarian stimulation to produce multiple eggs, retrieval of mature eggs, laboratory fertilisation and embryo culture, followed by transfer of one or more embryos into the uterus and support of the luteal phase as needed. Clinicians and embryologists adjust the details for each patient.

  1. Ovarian stimulation and monitoring to obtain several mature eggs.
  2. Egg retrieval using a transvaginal aspiration under ultrasound guidance.
  3. Fertilisation in the lab by mixing eggs and sperm or by injecting sperm directly into an egg.
  4. Embryo culture for a few days and optional genetic testing.
  5. Embryo transfer to the uterus or cryopreservation for later use.

Variations and supporting technologies

Several techniques modify or accompany IVF: intracytoplasmic sperm injection (ICSI) injects a single sperm into an egg to assist male-factor infertility; preimplantation genetic testing can screen embryos for specific genetic conditions; donor eggs, sperm or embryos expand options when a partner’s gametes are unavailable; and cryopreservation enables deferred transfer and fertility preservation.

Uses, success factors and considerations

IVF is indicated for many causes of subfertility such as blocked fallopian tubes, certain male-factor problems, unexplained infertility and ovulatory disorders. Success rates depend mainly on patient factors (especially age and ovarian reserve) and clinic practices. IVF raises social and ethical questions about embryo disposition, access, and regulation; patients also face emotional and financial burdens that are important to discuss before treatment.

Risks, history and impact

Risks include multiple pregnancy if more than one embryo implants, ovarian hyperstimulation syndrome in response to stimulation medications, and procedural complications. Since its development late in the 20th century, IVF has become a widely used reproductive tool that has transformed family-building options and prompted evolving legal and ethical frameworks worldwide. Ongoing research seeks to improve safety, success rates and equitable access.