Fertility Glossary - Reproductive Partners Fertility Center

A

ACTH

Produced by the pituitary gland, this hormone stimulates the adrenal gland. Abnormal levels of ACTH can sometimes be associated with infertility.

Adhesion

When bands of scar tissue form in reproductive organs and/or abdominal area that can impact fertility; endometriosis can often cause these bands.

Adrenal Androgens

When male hormones (which are produced by the adrenal gland) are elevated in women with PCOS, which cause fertility problems.

Agglutination

When sperm cells clump together instead of moving freely.

Amenorrhea (primary)

Having never menstruated by the age of 16.

Amenorrhea (secondary)

The absence of menstruation for three months or more in women who have menstruated in the past.

American Society of Reproductive Medicine (ASRM)

A group of fertility and reproductive specialists that teach, do research on and advocate for reproductive medicine.

Amniocentesis

Examining a fetus for abnormalities by using a needle to extract amniotic fluid from the womb.

Andrologist

A doctor who specializes in male health, specifically reproductive health and fertility.

Anovulation

Rare or lack of ovulation which can occur with or without menstruation.

Antibodies

Substances produced by the body that attack foreign matter to prevent infection but which may also cause infertility in some cases.

Antisperm Antibody Test

A test to see if antibodies on the surface of sperm are interfering with the sperm’s ability to move, travel through cervical mucus, or fertilize an egg.

Artificial Insemination (AI)

The injection of sperm directly into a female’s vagina, cervix, uterus or fallopian tubes in order to fertilize an egg.

Asherman’s Syndrome

A condition where scar tissue forms inside the uterus which may lead to infertility or menstrual irregularities.

Aspiration

The act of suctioning fluid or tissue from the body, typically performed with a needle or tube.

Assisted hatching

A procedure where the thick outer wall of an embryo is broken open to help facilitate implantation.

Assisted Reproductive Technologies (ART)

Fertility treatments that include procedures for both the egg and the sperm such as IUI, IVF, GIFT, ICSI and ZIFT.

Asthenozoospermia

Sperm that are considered to be poor quality due to reduced motility.

Azoospermia

When there are no sperm in a man’s semen which is sometimes caused by blockages.

B

Basal Body Temperature (BBT)

Temperature used to chart ovulation when taken every day first thing after awakening in the morning. The temperature rises and falls day to day due to changes in hormone levels Read more…

Beta HCG Test

A blood test used to measure the levels of HCG in early pregnancy.

Bicornuate uterus

An abnormality in the structure of the uterus that can cause problems with fertility and pregnancy such as fetal growth restriction. It can sometimes be fixed with surgery.

Blastocyst

The stage of an embryo that is reached around 5 days after the egg is fertilized.

Blastomere

A cell taken from a blastocyst by performing a biopsy.

Blighted ovum (egg)

A fertilized egg that implants in the uterus but does not continue to develop properly.

Bromocriptine (Parlodel)

A medication that treats tumors in the pituitary gland and therefore reduces prolactin levels.

C

Canceled cycle

This is when an ART cycle is stopped before being completed due to problems with follicle development, lack of fertilization, or other issues.

Candidiasis

An infection — also know as a yeast infection — sometimes found in the vagina that is caused by a common fungus with symptoms of burning, itching and discomfort.

Cervical mucus

Mucus produced by the cervix during a woman’s monthly cycle that changes consistency and increases in quantity as ovulation approaches.

Cervical smear

A cellular sample taken from the cervix and examined for cancerous cells or other abnormalities.

Cervix

The inch long canal at the lower end of the uterus and above the vagina through which blood passes during menstruation, sperm travels through to reach the fallopian tubes, and Read more…

Cervix, incompetent

A condition where the cervix opens prematurely during pregnancy before the baby is developed and labor is ready to begin.

Chemical pregnancy

When the egg implants itself but the embryo doesn’t develop. The vast majority of miscarriages fall into this category.

Chlamydia

A sexually transmitted disease (STD) which can damage the female and male reproductive systems causing infertility. Chlamydia can go without symptoms for years.

Chocolate cyst

An ovarian cyst with intracavitary hemorrhage and formation of a hematoma which contains old brown blood; often seen with endometriosis of the ovary.

Cilia

Tiny, hair like structures that help the egg move along within the fallopian tubes.

Cleavage

When a zygote (cell formed by fertilization) divides into enough cells to become a blastocyst.

Clinical pregnancy

When a pregnancy is confirmed through a clinical intervention like an ultrasound.

Clomiphene citrate

A medication — also known as clomid — used to trigger a surge of gonadotropins from the pituitary gland and stimulates ovulation to boost fertility

Complete Blood Count (CBC)

A blood test where red and white blood cells, hemoglobin and other factors are measured in order to diagnose and evaluate potential disease.

Corpus luteum

Endocrine tissue that secretes the hormone progesterone after ovulation and during pregnancy in order to boost implantation and help maintain the pregnancy.

Cryopreservation

When eggs, embryos, and/or sperm are preserved in a controlled freezing environment for fertility treatment, donation and ART.

Cushing’s syndrome

A condition where there is an excess of corticosteroids, such as cortisol, that can affect fertility and cause weight gain, male sex characteristics and other symptoms in women.

Cycle

A single round of fertility treatment that takes about a month.

Cyst

A sac surrounded by a membrane, which may or may not cause health problems.

Cytomegalovirus (CMV)

A member of the herpes groups of viruses. Most adults and children who contract CMV have no symptoms, although some people may get a fever, sore throat, fatigue and swollen Read more…

D

Danazol (danocrine)

This synthetic androgen drug is used to treat endometriosis. Side effects may include acne, changes in breast size, weight gain, and other symptoms.

DHEAS (Dihydroepiandrosterone Sulfate)

This weak male hormone is produced by the adrenal gland in some women that, in high doses, can cause excess hair growth and other symptoms. It is sometimes given to Read more…

Dilation and Curettage (D&C)

A procedure where the cervix is dilated (opened) and the uterine lining is scraped away. This is often performed after a miscarriage.

Donor egg

Eggs donated by a fertile woman that can be implanted in another woman for pregnancy.

Donor embryo transfer

A procedure where an embryo created from a donor egg and/or donor sperm are transferred to a woman’s uterus during IVF to help her get pregnant.

Donor insemination

A procedure where donor sperm is injected into a woman’s vagina, cervix, or uterus as part of artificial insemination (also known as intrauterine insemination).

Donor sperm

Sperm that has been donated by men who have been screened for illnesses and selected based on ethnicity, build and other characteristics. It is usually frozen and held for six Read more…

E

Ectopic pregnancy

This occurs when a fertilized egg implants in a woman’s body outside of the uterus — often in a fallopian tube — causing dangerous complications before it must be terminated.

Egg

Female sex cell/female gamete — also known as an ovum — which is released during ovulation and is fertilized by sperm during reproduction.

Egg collection

Procedure where eggs are collected from the ovaries by using a guided needle. Also known as Egg Retrieval.

Egg donation

The process by which a fertile woman donates her eggs to be used in the treatment of others or for research.

Egg retrieval

A procedure where ripe eggs are removed with a thin needle from the ovarian follicles for ICSI, IVF or other procedures.

Ejaculate

Fluid expelled by the male containing sperm.

Embryo

One of the earliest stages of the human fetus, between implantation and eight weeks of pregnancy.

Embryo biopsy

The removal of one or two cells from an embryo in vitro in preparation for genetic screening.

Embryo culture

When embryos develop in vitro for two to six days after the egg has been fertilized by the sperm.

Embryo freezing

Extra embryos that are not needed during a cycle can be frozen and stored for future use in a process called cryopreservation.

Embryo storage

The storage of one or more embryos to use in the future by freezing (cryopreservation).

Embryo transfer

When a fertilized embryo is placed into the uterus using a catheter as part of IVF and other ART procedures.

Endocrinology

The medical study of hormones, glands, hormonal systems, and how they all interact and work together.

Endometrial biopsy

A procedure where a small sample of the uterine lining (endometrium) is taken to evaluate it for abnormalities.

Endometriosis

A condition where endometrial tissue is present in abnormal locations such as inside the fallopian tubes, on the ovaries, and in the peritoneal cavity, which often causes painful menstruation and Read more…

Endometrium

The tissue that lines the inside of the uterus.

Endorphins

Chemicals produced by the body, such as during intense exercise, that induce opiate like feelings including pain relief.

Epididymis

A tube located near a man’s testicles that holds sperm.

Estradiol

A form of the hormone estrogen that is secreted by the ovaries.

Estrogen

A female sex hormone that stimulates the development of female sex characteristics and the maturation of the reproductive system.

F

Fallopian Tubes

Two hollow tubes on either side of the uterus through which the egg is released during ovulation and where the egg and sperm meet to begin the process of fertilization.

Fertility specialist

Doctors who specialize in diagnosing and treating infertility such as a Reproductive Endocrinologist.

Fertilization

When the egg and sperm combine to begin the process toward pregnancy.

Fetus

Beginning at eight weeks after implantation, an embryo is called a fetus until it is born.

Fibroid

A benign tumor — also called a myoma — made of muscle cells and other tissues that is found in the uterine wall.

Follicle

A tiny sack within the ovary where a woman’s egg grows and develops each month. During ovulation, the follicle expels the egg into the fallopian tube.

Follicle stimulating hormone (FSH)

A hormone produced in the pituitary gland that stimulates ovarian follicles to grow. It can become elevated as a woman ages and her ovarian reserve diminishes. Synthetic versions of FSH Read more…

Follicular fluid

The fluid that nourishes the developing egg inside of the ovarian follicles.

Follicular phase

The first phase of the monthly cycle, starting with the first day of menstrual bleeding, when ovarian follicles start to develop.

Fresh and frozen cycles

In most cases, the eggs collected from a patient are mixed with her partners fresh sperm to produce embryos within a few days. These fresh embryos are then transferred back Read more…

Fundus

The upper part of the uterus.

G

Gamete

A mature sex cell such as the egg or the sperm.

Gamete Intrafallopian Transfer (GIFT)

An assisted reproductive technique where a female’s eggs are extracted from the ovaries, mixed with sperm in a lab, and then placed in the fallopian tubes where fertilization can occur.

Gene

The unit of inheritance. Everyone inherits two copies of each gene. A dominantly inherited genetic disease occurs when only one copy of the gene is sufficient to produce the disease Read more…

Genome

The basic set of genes in the chromosomes in any cell, organism or species.

Gestation

The time between conception and the birth of a baby.

Gonad

Reproductive glands that produce sex cells (eggs and sperm) and hormones; in women, the ovaries, and in males, the testes.

Gonadotropin

Hormones used during ovulation induction to encourage follicular and egg development.

Gonadotropin Releasing Hormone (GnRH)

The hypothalamus secretes this hormone, stimulating the release of gonadotropins (LH and FSH), which stimulate the testicles or ovaries.

H

Hamster Test (HEPT)

When a man’s sperm are mixed with hamster eggs in a dish and the sperm are observed to see how many penetrate the eggs. This test is also known as Read more…

Hirsutism

A condition that often occurs with PCOS where women have excess body and facial hair, due to high levels of androgens.

Hormonal assay

Hormone test that checks for levels of hormones like FSH (follicle stimulating hormone), LH (luteinizing hormone), DHEA S (dehydroepiandresterone), prolactin and progesterone.

Hormone

Chemicals produced in one organ of the body that regulates activities of other organs.

Hostile mucus

Cervical mucus that impedes the travel of sperm into the fallopian tubes for fertilization.

Human chorionic gonadotropin (HCG)

In early pregnancy this hormone helps to maintain progesterone levels; it is sometimes used to trigger ovulation.

Human menopausal gonadotropin (HMG)

This hormone is used to stimulate ovulation and is made of LH and FSH.

Hydrocele

Fluid accumulation in the scrotum.

Hyperprolactinemia

High amounts of prolactin in the blood that can suppress LH and FSH production, affecting male and female fertility.

Hyperstimulation (Ovarian Hyperstimulation Syndrome OHSS)

A serious complication that occurs with medically induced ovulation where the ovaries swell and mild to severe side effects may occur.

Hyperthyroidism

Excessive activity of the thyroid that can affect female ovulation and fertility.

Hypoestrogenic

Estrogen levels that are lower than normal.

Hypospermatogenesis

The production of sperm in low numbers.

Hypothalamus

The part of the brain that secretes GnRH, which enables the release of LH and FSH to stimulate the ovaries and testes.

Hypothyroidism

The thyroid gland does not produce enough thyroid hormone, leading to a slow metabolism and fatigue, and impaired fertility.

Hysterectomy

The partial or total removal of the uterus, ovaries and /or fallopian tubes that can lead to sterility.

Hysterosalpingogram (HSG)

An X-ray examination using a special dye injected into the uterus to observe the uterus and fallopian tubes.

Hysteroscope

A device, similar to a laparoscope, that allows for interior visual exam of the cervix and uterus.

I

Immature sperm (germinal cell)

Sperm that are not fully mature and that have low motility.

Implantation

After fertilization, the egg starts to embed into the uterine lining where it starts to develop as an embryo.

Impotence

A situation where a man cannot have erections or ejaculate semen.

In vitro fertilization (IVF)

Meaning in glass, this assisted reproductive technology (ART) process involves ovulation induction, extraction of the egg from the ovary, and combining the egg with the sperm outside of the female’s Read more…

Infertility

For women under 35, this means the inability to get pregnant or carry a pregnancy to term when trying to conceive one year, and for women over 35, infertility is Read more…

Injectables

Fertility medications (usually ovulation induction medications) that are injected.

Inner cell mass

A clump of cells growing within and to one side of the blastocyst from which the embryo develops.

Insemination

The introduction of sperm into a woman’s body for fertilization.

Intra Uterine insemination (IUI)

Sperm are collected and washed to prepare for insemination directly into a woman’s uterus with a catheter and syringe.

Intracervical Insemination (ICI)

Artificial insemination procedure where sperm are injected directly into a woman’s cervix with a syringe and catheter.

Intracytoplasmic sperm injection (ICSI)

The injection of a single sperm into an egg, usually used with IVF.

K

Karyotyping

A test analyzing chromosomes for potential genetic abnormalities.

Klinefelter’s Syndrome

When a male is born with two X and one Y chromosome, causing possible feminine qualities and infertility.

L

Laparoscope

A telescopic instrument that is inserted into a small incision in the abdomen, for viewing of the pelvis, ovaries, uterus and fallopian tubes.

Laparotomy

Surgery that opens the abdominal area to treat a variety of issues, including removing adhesions and repairing tubes.

Lavage

The removal of a fertilised egg or cleavage stage embryo from the womb before implantation by washing out the uterine cavity.

Leydig cell

Cell in the testes that produces male hormones, including testosterone, and is stimulated by LH from the pituitary gland.

LH surge

A surge of LH followed by the release of an egg from a follicle in the ovaries.

Luteal phase

The luteal phase is a stage of the menstrual cycle. It occurs after ovulation and before the start of menstruation. During this phase, the lining of the uterus normally becomes Read more…

Luteal phase defect (or deficiency) (LPD)

Often due to a short luteal phase, the uterus will not be able to sustain a pregnancy due to abnormal hormone levels. May cause recurrent miscarriages.

Luteinizing hormone (LH)

A hormone that stimulates the ovary to release an egg during ovulation and also stimulates testosterone production in males.

M

Male factor infertility

Infertility due to male health or anatomic reasons.

Menorrhagia

Very heavy menstrual flow, or menses that lasts longer than normal.

Menstruation

Monthly cycle of bleeding where the uterine lining is shed after a woman fails to achieve pregnancy (also called menses, menstrual cycle).

Metrorrhagia

Appearance of bleeding or spotting in the middle of the menstrual cycle.

Micromanipulation

Procedure where a microscopic single sperm is injected into an egg, as with ICSI.

Miscarriage

Spontaneous expulsion of the embryo or fetus from the uterus in the first 20 weeks gestation, which occurs in about 20% of pregnancies (also called abortion).

Mitochondria

Structures present in human cells which are often referred to as the cell’s ‘batteries’ because they generate the majority of a cell’s energy supply. They contain a small amount of Read more…

Mittleschmerz

Occurring around ovulation, some women notice this as a slight pain or cramping low in the abdomen.

Morphology

The size and shape of sperm.

Morula

The ball of cells which forms at about 3 – 4 days after insemination of the egg, resulting from the cleavage of the fertilized ovum.

Motility

The ability of sperm to move by themselves.

Myomectomy

The surgical removal of benign fibroid tumors from the uterine wall.

N

Natural cycle

Treatment cycle in which no drugs are given to stimulate egg production.

Nucleus

The part of a cell which contains the genetic material DNA.

O

Oligmenorrhea

Menstrual periods occurring less frequently than normal.

Oligospermia

Low levels of sperm in the semen.

Oocyte

The female sex cell that is produced in the ovaries (also see egg, ovum, gamete).

Oocyte retrieval

When a needle is inserted into the ovarian follicles to extract eggs during surgery.

Ovarian cyst

A fluid-filled sac in the ovary that can vary in size; may or may not be problematic, but can sometimes cause pain and can be an indicator of PCOS if Read more…

Ovarian failure

A situation where levels of FSH in the blood are elevated, usually indicating a lack of ovarian response to FSH stimulation.

Ovarian Hyperstimulation Syndrome (OHSS)

A serious complication following stimulation of the ovaries with gonadotrophin drugs.

Ovary

Female sex glands that produce eggs (ova) and female hormones (estrogen and progesterone).

Ovulation

When the ovary releases a mature egg in the middle of the menstrual cycle, often around day 14.

Ovulation induction

Use of a group of medications (fertility drugs) to improve hormone levels and/or boost the development and release of eggs during fertility treatment.

Ovulatory failure (anovulation)

Lack of ovulation during the menstrual cycle (no egg is released for fertilization).

Ovulatory phase

Occurs in the middle of the menstrual cycle; the release of the egg for fertilization.

Ovum

Female sex cell that contains genetic material for the embryo (also called egg, gamete).

P

Pap test

A test to detect abnormal (cancerous) cells in the cervix.

Pelvic inflammatory disease (PID)

Infection within the pelvis that can cause fever, pain and possibly infertility and may lead to the development of scar tissue and/or tubal problems.

Pituitary gland

A gland located at the base of the brain known as the master gland of the endocrine system that releases and regulates the body’s hormones.

Placenta

This organ connects the fetus to the uterus via the umbilical cord, providing nutrients and oxygen for development.

Polycystic Ovarian Syndrome (PCOS or Stein Leventhal Syndrome)

A hormonal disturbance linked to infrequent ovulation that may include symptoms like menstrual problems, weight gain, pain, infertility, and hair/skin problems.

Post coital test (PCT)

A test done several hours after intercourse to look for the presence of healthy, active sperm, fertile-quality cervical mucus, and healthy sperm-mucus interaction.

Preimplantation Genetic Diagnosis (PGD)

In conjunction with IVF, where a recognised practitioner removes one or two cells from an embryo, for those cells to be tested for specific genetic disorders/characteristics before embryo transfer takes Read more…

Premature ovarian failure (POF)

A syndrome associated with high levels of gonadotropins and low levels of estrogen, often causing menstruation to end before age 40.

Primary infertility

Infertility in couples that have never had a successful pregnancy or in couples that have gotten pregnant but never had a live birth.

Progesterone

The corpus luteum in the ovary produces this hormone that prepares the uterus for pregnancy after ovulation.

Prolactin

A hormone that helps women to make breastmilk after childbirth and in women that are not nursing, abnormal levels can hinder ovulation, possibly causing infertility.

Pronuclear stage tubal transfer (PROST) (ZIFT)

An assisted reproductive technology (ART) procedure where eggs are retrieved, fertilized by sperm in vitro and then transferred to the woman’s body before the cells divide.

Prostaglandins

These hormone-like substances are found in both men and women while sperm washing techniques remove prostaglandins during artificial insemination to reduce cramping in the woman’s body.

Prostate gland

A male gland circling the urethra, the tube that carries urine out of the body.

R

Recurrent Pregnancy Loss

Refers to two or more failed pregnancies, especially if they happen successively.

Reproductive Endocrinologist (RE)

Doctors trained in obstetrics and gynecology that are board certified in reproductive endocrinology.

Retrograde Ejaculation

When the semen is ejaculated, it travels backwards into the bladder due to a problem with the sphincter muscle.

Rh Factor

A protein found in red blood cells in most people, yet if the fetus has Rh factor in the blood but the mother does not, the mother’s body will produce Read more…

Round Spermatid Nucleus Injection (ROSNI)

An experimental fertilization technique in which immature sperm cells are removed from the testicle and the genetic material is injected into an egg.

S

Salpingectomy

The removal of the fallopian tubes which is done during surgery.

Scrotum

The sac of skin on the external genitalia of the male that contains the testes.

Secondary infertility

Infertility that occurs after a couple have had a successful pregnancy and/or live birth.

Secondary sex characteristics

Physical characteristics such as breasts, facial and body hair, voice changes and other characteristics that appear during puberty, distinguishing males from females.

Semen

A liquid medium that carries the male’s sperm outside of his body and protects and nourishes the sperm.

Semen analysis

Examination of semen under a microscope to assess sperm count, movement (motility), and the size and shape of the sperm.

Singleton Birth

The birth of a single baby at a live birth event.

Sonogram (ultrasound)

These are high-frequency sound waves used to monitor pregnancy and observe images of internal body parts to detect any abnormalities.

Sperm

Male sex cell carried in semen that holds genetic information from the male (also called gamete).

Sperm Bank

At a sperm bank, sperm are kept frozen in liquid nitrate to be thawed later for use in insemination and ART procedures.

Sperm maturation

Sperm take 90 days to fully mature as they grow and attain better motility for fertilization.

Sperm morphology

Refers to the size and shape of the sperm and abnormal sperm morphology can indicate male factor infertility.

Sperm motility

Movement of sperm, and good motility is a sign of male fertility.

Sperm penetration

Refers to the ability of a sperm to penetrate an egg during fertilization.

Sperm penetration assay (SPA)

A test usually done before IVF where a man’s sperm are mixed with hamster eggs to see how many sperm penetrate the egg (also called hamster test).

Sperm wash

Washing of sperm, a procedure done for artificial insemination, removes toxic chemicals, reducing cramping and allergic reactions in females after artificial insemination.

Sterility

A condition where an individual is completely unable to conceive.

Stillbirth

The loss of a fetus between 20 weeks gestation and birth.

Stimulated cycle

A treatment cycle in which stimulation drugs are used to produce more eggs than usual in the woman’s monthly cycle.

Superovulation

The use of fertility drugs to stimulate a woman to release multiple eggs (also called controlled ovarian hyperstimulation or COH).

Surrogacy

The process of a woman carrying a baby for another person. Full surrogacy involves the implantation of an embryo created using either the eggs and sperm of the intended parents, Read more…

Surrogate mother

A woman who gets pregnant and gives birth for a couple who are infertile.

T

Testicles

Pair of male reproductive glands that produce testosterone and sperm.

Testicular/epididymal sperm aspiration (TESA)

Sperm are extracted from the testis or epididymis with a needle.

Testosterone

A male sex hormone necessary for the development of male secondary sex characteristics, sex drive and sperm development.

TET (tubal embryo transfer)

A procedure that occurs after cell division of a fertilized egg when the egg is then placed directly into the fallopian tubes.

Trisomy

A syndrome reflecting the presence of three chromosomes of one type instead of the normal human chromosome number of two. An example is Trisomy 21 resulting in Down’s syndrome.

Tubal Ligation

A permanent form of female birth control where the fallopian tubes are cut or tied, making the woman sterile.

Turner’s syndrome

A condition where a female has one X-chromosome and no Y-chromosomes, resulting in limited height, underdeveloped ovaries, lack of ovulation and infertility.

U

Ultrasound

High-frequency sound waves used to monitor pregnancy and observe images of internal body parts to detect any abnormalities (also called sonogram).

Unexplained Infertility

When no reason or cause can be found for a couple’s infertility problems.

Unicornuate uterus

Uterine abnormality characterized by a smaller size and a single horn shape in the uterus that can cause discomfort and infertility.

Unstimulated cycle

No drugs are given to stimulate egg production. Also known as a natural cycle.

Urethra

The tube that carries urine outside of the body in males and females, and in males this tube also carries semen outside of the body.

Urologist

A doctor who specializes in urinary and urogenital medicine.

Uterine tube

One of two tubes connecting the ovaries to the uterus through which the egg is released during ovulation, where it waits to be fertilized (also called fallopian tube).

Uterus

A muscular organ that contains, protects and nourishes the embryo and fetus during pregnancy (also called womb).

V

Vaginal ultrasound

Placing a probe into the vagina and using sound waves to view the follicles, ovaries, eggs, fetus, and other internal organs.

Vaginitis

Inflammation of the vagina caused by a fungal or bacterial infection and a condition that may cause irritation and discharge.

Varicocele

Varicose veins found in the scrotum that cause an abnormal flow of blood in the male genitalia and can sometimes lead to male infertility.

Vas Deferens

Pair of tubes which connect the epididymis to the urethra and transport sperm during ejaculation.

Vasectomy

A permanent form of male birth control where the vas deferens is blocked.

Vasectomy Reversal

A surgical procedure to reconnect the vas deferens after a vasectomy that restores fertility in many cases.

Venereal disease

Sexually transmitted infections including Chlamydia, gonorrhea, syphilis and others that can cause illness and infertility.

Vitrification

The process of gamete or embryo storage (cryopreservation) that avoids ice crystal formation by the use of high cooling rates and a high concentration of cryoprotectant.

Z

Zona Pellucida

The thick transparent membrane surrounding an ovum before implantation.

Zygote Intrafallopian Transfer (ZIFT)

An ART procedure where a fertilized egg is transferred into the fallopian tube one day after fertilization.