From Wikipedia, the free encyclopedia
This article is about pregnancy in humans. For pregnancy in other animals, see pregnancy (mammals). Page semi-protected
Classification and external resources |
A pregnant woman. |
ICD-10 | Z33 |
ICD-9 | 650 |
DiseasesDB | 10545 |
MedlinePlus | 002398 |
eMedicine | article/259724 |
MeSH | D011247 |
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 henceforth 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.
Contents [hide] 1 Terminology 2 Progression 2.1 Initiation 2.2 Duration 2.2.1 Preterm, term and postterm 2.3 Childbirth 2.4 Postnatal period 3 Diagnosis 4 Physiology 4.1 First trimester 4.2 Second trimester 4.3 Third trimester 4.4 Embryonic and fetal development and ultrasound imaging 4.5 Physiological changes 5 Management 5.1 Nutrition 5.2 Weight gain 5.3 Immune tolerance 5.4 Medication use 5.5 Exposure to toxins 5.6 Sexual activity during pregnancy 5.7 Exercise 6 Complications 6.1 Ectopic pregnancy 7 Concomitant diseases 8 Stem cell collection 9 Society and culture 9.1 Arts 9.2 Demography 9.3 Desired and undesired pregnancies 9.3.1 Infertility 9.3.2 Abortion 9.4 Legal protection for pregnant women 9.5 Post-menopausal pregnancies 10 See also 11 References 12 External links | TerminologyOne scientific term for the state of pregnancy is gravidity (adjective "gravid"), Latin for "heavy" and a pregnant female is sometimes referred to as a gravida. Similarly, the termparity (abbreviated as "para") is used for the number of times a female has given birth, counting twins and other multiple births as one pregnancy, and usually including stillbirths. Medically, a woman who has never been pregnant is referred to as a nulligravida, a woman who is (or has been only) pregnant for the first time as a primigravida, and a woman in subsequent pregnancies as a multigravida or multiparous. Hence, during a second pregnancy a woman would be described as gravida 2, para 1 and upon live delivery asgravida 2, para 2. An in-progress pregnancy, as well as abortions, miscarriages, or stillbirths account for parity values being less than the gravida number. In the case of twins, triplets etc., gravida number...