In vitro fertilisationIn vitro fertilisation (IVF) is a process of fertilisation where an egg is combined with sperm in vitro ("in glass"). The process involves monitoring and stimulating a woman's ovulatory process, removing an ovum or ova (egg or eggs) from her ovaries and letting sperm fertilise them in a culture medium in a laboratory. After the fertilised egg (zygote) undergoes embryo culture for 2–6 days, it is transferred by catheter into the uterus, with the intention of establishing a successful pregnancy.
Embryo transferEmbryo transfer refers to a step in the process of assisted reproduction in which embryos are placed into the uterus of a female with the intent to establish a pregnancy. This technique (which is often used in connection with in vitro fertilization (IVF), may be used in humans or in animals, in which situations the goals may vary. Embryo transfer can be done at day two or day three, or later in the blastocyst stage, which was first performed in 1984.
Double fertilizationDouble fertilization is a complex fertilization mechanism of flowering plants (angiosperms). This process involves the joining of a female gametophyte (megagametophyte, also called the embryo sac) with two male gametes (sperm). It begins when a pollen grain adheres to the stigma of the carpel, the female reproductive structure of a flower. The pollen grain then takes in moisture and begins to germinate, forming a pollen tube that extends down toward the ovary through the style.
EmbryoAn embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres are arranged as a solid ball that when reaching a certain size, called a morula, takes in fluid to create a cavity called a blastocoel.
PregnancyPregnancy is the time during which one or more offspring develops (gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins. Pregnancy usually occurs by sexual intercourse, but can also occur through assisted reproductive technology procedures. A pregnancy may end in a live birth, a miscarriage, an induced abortion, or a stillbirth. Childbirth typically occurs around 40 weeks from the start of the last menstrual period (LMP), a span known as the gestational age.
FertilisationFertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. While processes such as insemination or pollination which happen before the fusion of gametes are also sometimes informally referred to as fertilisation, these are technically separate processes. The cycle of fertilisation and development of new individuals is called sexual reproduction.
InfertilityInfertility is the inability of a person, animal or plant to reproduce by natural means. It is usually not the natural state of a healthy adult, except notably among certain eusocial species (mostly haplodiploid insects). It is the normal state of a human child or other young offspring, because they have not undergone puberty, which is the body's start of reproductive capacity. In humans, infertility is the inability to become pregnant after one year of unprotected and regular sexual intercourse involving a male and female partner.
OvulationOvulation is the release of eggs from the ovaries. In women, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. In addition, the uterine lining (endometrium) is thickened to be able to receive a fertilized egg. If no conception occurs, the uterine lining as well as the egg will be shed during menstruation. Ovulation occurs about midway through the menstrual cycle, after the follicular phase.
Follicle-stimulating hormoneFollicle-stimulating hormone (FSH) is a gonadotropin, a glycoprotein polypeptide hormone. FSH is synthesized and secreted by the gonadotropic cells of the anterior pituitary gland and regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and luteinizing hormone (LH) work together in the reproductive system. FSH is a 35.5 kDa glycoprotein heterodimer, consisting of two polypeptide units, alpha and beta.
SpermSperm (: sperm or sperms) is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, which are known as spermatozoa, while some red algae and fungi produce non-motile sperm cells, known as spermatia. Flowering plants contain non-motile sperm inside pollen, while some more basal plants like ferns and some gymnosperms have motile sperm.
Complications of pregnancyComplications of pregnancy are health problems that are related to, or arise during pregnancy. Complications that occur primarily during childbirth are termed obstetric labor complications, and problems that occur primarily after childbirth are termed puerperal disorders. While some complications improve or are fully resolved after pregnancy, some may lead to lasting effects, morbidity, or in the most severe cases, maternal or fetal mortality. Common complications of pregnancy include anemia, gestational diabetes, infections, gestational hypertension and pre-eclampsia.
Ectopic pregnancyEctopic pregnancy is a complication of pregnancy in which the embryo attaches outside the uterus. Signs and symptoms classically include abdominal pain and vaginal bleeding, but fewer than 50 percent of affected women have both of these symptoms. The pain may be described as sharp, dull, or crampy. Pain may also spread to the shoulder if bleeding into the abdomen has occurred. Severe bleeding may result in a fast heart rate, fainting, or shock. With very rare exceptions, the fetus is unable to survive.
Fertility testingFertility testing is the process by which fertility is assessed, both generally and also to find the "fertile window" in the menstrual cycle. General health affects fertility, and STI testing is an important related field. Healthy women are fertile from puberty until menopause, although fertility is typically much reduced towards the extremes of this period. The onset of puberty is typically identified by menarche and the presence of secondary sexual characteristics such as breast development, the appearance of pubic hair and changes to body fat distribution.
Luteinizing hormoneLuteinizing hormone (LH, also known as luteinising hormone, lutropin and sometimes lutrophin) is a hormone produced by gonadotropic cells in the anterior pituitary gland. The production of LH is regulated by gonadotropin-releasing hormone (GnRH) from the hypothalamus. In females, an acute rise of LH known as an LH surge, triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell–stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone.
Pregnancy ratePregnancy rate is the success rate for getting pregnant. It is the percentage of all attempts that leads to pregnancy, with attempts generally referring to menstrual cycles where insemination or any artificial equivalent is used, which may be simple artificial insemination (AI) or AI with additional in vitro fertilization (IVF). There is no universally accepted definition of the term. Thus in IVF pregnancy rates may be based on initiated treatment cycles, cycles that underwent oocyte retrieval, or cycles where an embryo transfer was performed.
Female infertilityFemale infertility refers to infertility in women. It affects an estimated 48 million women, with the highest prevalence of infertility affecting women in South Asia, Sub-Saharan Africa, North Africa/Middle East, and Central/Eastern Europe and Central Asia. Infertility is caused by many sources, including nutrition, diseases, and other malformations of the uterus. Infertility affects women from around the world, and the cultural and social stigma surrounding it varies.
Diabetes and pregnancyFor pregnant women with diabetes, some particular challenges exist for both mother and child. If the pregnant woman has diabetes as a pre-existing disorder, it can cause early labor, birth defects, and larger than average infants. Therefore, experts advise diabetics to maintain blood sugar level close to normal range about 3 months before planning for pregnancy. When type 1 diabetes mellitus or type 2 diabetes mellitus is pre-existing, planning in advance is emphasized if one wants to become pregnant, and stringent blood glucose control is needed before getting pregnant.
Beginning of pregnancy controversyControversy over the beginning of pregnancy occurs in different contexts, particularly as it is discussed within the debate of abortion in the United States. Because an abortion is defined as ending an established pregnancy, rather than as destroying a fertilized egg, depending on when pregnancy is considered to begin, some methods of birth control as well as some methods of infertility treatment might be classified as causing abortions.
Sperm motilitySperm motility describes the ability of sperm to move properly through the female reproductive tract (internal fertilization) or through water (external fertilization) to reach the egg. Sperm motility can also be thought of as the quality, which is a factor in successful conception; sperm that do not "swim" properly will not reach the egg in order to fertilize it. Sperm motility in mammals also facilitates the passage of the sperm through the cumulus oophorus (a layer of cells) and the zona pellucida (a layer of extracellular matrix), which surround the mammalian oocyte.
Male infertilityMale infertility refers to a sexually mature male's inability to impregnate a fertile female. In humans it accounts for 40–50% of infertility. It affects approximately 7% of all men. Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity. More recently, advance sperm analyses that examine intracellular sperm components are being developed.
