In vitro fertilization (IVF)

Overview

In vitro fertilization (IVF) is an assisted reproductive technique (ART) wherein fertilization of sperm and egg occurs outside the body within a laboratory environment. It is a complex process where eggs are retrieved from ovaries and manually combined with sperm for fertilization. The fertilized egg (an embryo) is placed inside a uterus many days after fertilization, and pregnancy occurs when it implants itself into the uterine wall. 

Reasons for IVF

IVF is chosen for many reasons, like infertility issues when one of the partners has an existing health condition, failure of other fertility methods, or advanced maternal age. It is one of the reproductive options for same-sex couples and for individuals who want to have a baby without a sexual partner. IVF is also an option for those with conditions such as blocked tubes, endometriosis, low sperm count, PCOS, genetic risks, unexplained infertility, or seeking fertility preservation due to health issues or cancer treatment.

IVF Procedure

The process entails harvesting mature eggs from the ovaries, then fertilizing or impregnating them with sperm in a laboratory to generate embryos. Subsequently, these embryos are transferred to the uterus for potential implantation. A complete IVF cycle usually lasts 2 to 3 weeks. Sometimes, IVF can be prolonged due to the splitting of these steps into different parts. 

IVF can use an individual's eggs and sperm or may be borrowed from a known or unknown donor. Sometimes, a gestational carrier carries the implanted embryo. 

Sometimes, certain medications have to be taken to produce multiple eggs and overcome the issues with fertilization. Hormonal shots of follicle-stimulating hormone (FSH) or a luteinizing hormone (LH) that stimulate ovaries to produce more eggs or hormonal shots of human chorionic gonadotropin to ripen and release the eggs from the follicles may be needed. Other medications delay ovulation, and progesterone supplements to implant the embryo in the uterus may be required. 

Vaginal ultrasound and specific blood tests are prescribed by healthcare professionals to track the developing follicles and understand the response to ovarian stimulation medications. 

Collection of Eggs and Sperm

Eggs are collected from both ovaries before ovulation and almost 3 days after the final shot of fertility treatment in the doctor's office. Sometimes, medication can be given to relax and decrease the pain. Then, using an ultrasound device placed in the vagina, follicles are located, and eggs are collected using a thin needle. Multiple eggs are generally collected in 20 minutes. 

Semen is collected from the partner on the day of egg retrieval or ahead and frozen. If a male cannot ejaculate the semen through masturbation, testicular aspiration is done to collect the sperm directly from the testes. 

Both the healthy eggs and sperm are mixed using a conventional insemination procedure and stored in an incubator. If this does not work, then intracytoplasmic sperm injections are injected directly into the egg. After about a week after fertilization, embryos hatch. These embryos are collected in a syringe along with some fluid. A catheter is placed in the uterus through the vagina and cervix, through which embryos are implanted into the uterus. 

Preparation before IVF

Before starting a cycle of IVF using one's eggs and sperm, various screening tests need to be done. These include ovarian reserve testing, which is a blood test to know the number of eggs available in the body, also called egg supply. Blood tests, along with an ultrasound of the ovaries, help to predict the ovaries' response to fertility medicines.

An analysis of semen, which is a fluid containing sperm, is done to check the amount of sperm, its shape, and its motility. These tests are done as a part of an initial fertility evaluation or shortly before the start of an IVF treatment cycle. Infectious disease screening procedure where both the partners are screened for diseases such as HIV.

A practice embryo transfer test is needed to understand the depth of the uterus. Though this procedure doesn't place an actual embryo in the uterus, it helps to determine the technique that's going to be successful when one or more actual embryos are placed.

A Uterine exam where the inside lining of the uterus is checked before starting IVF. Sono-hysterography involves introducing fluid through the cervix into the uterus via a thin plastic tube to obtain detailed ultrasound images of the uterine lining. Hysteroscopy is also done using a thin, flexible, lighted telescope inserted through the vagina and cervix into the uterus to visualize the uterus.

The success of IVF

It takes about a week to 10 days for the embryo to attach to the uterus after egg retrieval. At least 12 days after retrieving the eggs, a blood test is done to confirm the pregnancy. If the pregnancy does not happen, then the entire cycle must be repeated. 

Risks of IVF

There are certain risk factors associated with IVF during retrieving the egg, like bleeding, infections, and damage to other internal organs. Others include swollen and painful ovaries, miscarriages, ectopic pregnancies, multiple pregnancies, birth defects, premature delivery or low birth weight of the newborn, and rarely cancers. 

Conclusion

In vitro fertilization (IVF) serves as a beacon of hope for those grappling with infertility or reproductive hurdles, offering a route to parenthood through assisted reproduction. This complex procedure involves harvesting eggs, fertilizing them with sperm in a controlled setting, and implanting viable embryos into the uterus. Despite the inherent risks and uncertainties, IVF stands as a valuable option for countless individuals yearning to realize their dreams of having a child. Through continued advancements and compassionate care, IVF continues to illuminate the path toward building families and nurturing cherished bonds.