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.
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.
Granulocyte colony-stimulating factorGranulocyte colony-stimulating factor (G-CSF or GCSF), also known as colony-stimulating factor 3 (CSF 3), is a glycoprotein that stimulates the bone marrow to produce granulocytes and stem cells and release them into the bloodstream. Functionally, it is a cytokine and hormone, a type of colony-stimulating factor, and is produced by a number of different tissues. The pharmaceutical analogs of naturally occurring G-CSF are called filgrastim and lenograstim.
UterusThe uterus (from Latin uterus, : uteri) or womb (wuːm) is the organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic and fetal development of one or more embryos until birth. The uterus is a hormone-responsive sex organ that contains glands in its lining that secrete uterine milk for embryonic nourishment. The term uterus is also applied to analogous structures in some non-mammalian animals.
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.
Preimplantation genetic diagnosisPreimplantation genetic diagnosis (PGD or PIGD) is the genetic profiling of embryos prior to implantation (as a form of embryo profiling), and sometimes even of oocytes prior to fertilization. PGD is considered in a similar fashion to prenatal diagnosis. When used to screen for a specific genetic disease, its main advantage is that it avoids selective abortion, as the method makes it highly likely that the baby will be free of the disease under consideration.
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.
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.
PlacentaThe placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner.
GestationGestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for example in a multiple birth. The time interval of a gestation is called the gestation period. In obstetrics, gestational age refers to the time since the onset of the last menses, which on average is fertilization age plus two weeks.
