Pregnancy is the fertilization and development of one or more offspring, known as an embryo or fetus, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets. Childbirth usually occurs about 38 weeks after conception; in women who have a menstrual cycle length of four weeks, this is approximately 40 weeks from the start of the last normal menstrual period (LNMP). Human pregnancy is the most studied of all mammalian pregnancies. Conception can be achieved through sexual intercourse or assisted reproductive technology.

An embryo is the developing offspring during the first 8 weeks following conception, and subsequently the term fetus is used until birth. 40% of pregnancies in the United States and United Kingdom are unplanned, and between a quarter and half of those unplanned pregnancies were unwanted pregnancies. Of those unintended pregnancies that occurred in the US, 60% of the women used birth control to some extent during the month pregnancy occurred.

In many societies’ medical or legal definitions, human pregnancy is somewhat arbitrarily divided into three trimester periods, as a means to simplify reference to the different stages of prenatal development. The first trimester carries the highest risk of miscarriage (natural death of embryo or fetus). During the second trimester, the development of the fetus can be more easily monitored and diagnosed. The beginning of the third trimester often approximates the point of viability, or the ability of the fetus to survive, with or without medical help, outside of the uterus.

Read more about Pregnancy:  Terminology, Diagnosis, Physiology, Management, Complications, Concomitant Diseases, Stem Cell Collection, Society and Culture

Other articles related to "pregnancy":

Bittersweet Love - Plot
... couple learns that they are half-siblings, with a pregnancy already underway ... the fetal weight is still low, they may be able to terminate the pregnancy due to her situation ... The couple spend the rest of the pregnancy from their friends and family ...
Alcoholism In Family Systems - Pregnancy
... in infants and children is not as impacted by mothers who stopped alcohol consumption early in pregnancy, even if it was resumed after giving birth ... six year-olds with alcohol exposure during the second-trimester of pregnancy showed lower academic performance and problems with reading, spelling, and mathematical ...
Pregnancy - Society and Culture - Post-menopausal Pregnancies
... pregnancies have occurred, and there are several known cases of older women carrying a pregnancy to term, usually with in vitro fertilization of a donor egg ...
Craniopagus Twins - Medical Procedures Pre and Post-Partum
... standard ultrasound equipment during mid-pregnancy ... Many parents make the difficult decision to terminate pregnancy due to the prognosis and quality of life issues that the twins would have to deal with ... can vary a parents likelihood of terminating pregnancy ...
Abortion In Poland
... When the woman's life or health is endangered by the continuation of pregnancy, When the pregnancy is a result of a criminal act, or When the fetus is seriously malformed Unlike in other ... a woman to carry out illegal termination of her pregnancy is a criminal act in the same way as illegal abortion is ...

Famous quotes containing the word pregnancy:

    It is now quite lawful for a Catholic woman to avoid pregnancy by a resort to mathematics, though she is still forbidden to resort to physics and chemistry.
    —H.L. (Henry Lewis)

    There are highly gifted spirits who are always infertile simply because, owing to a weakness in temperament, they are too impatient to wait out their pregnancy to term.
    Friedrich Nietzsche (1844–1900)

    If pregnancy were a book they would cut the last two chapters.
    Nora Ephron (20th century)