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	:''For a broader view of pregnancy in ]s see ]. For the medicine of pregnancy, see ].''		:''For a broader view of pregnancy in ]s see ]. For the medicine of pregnancy, see ].''

	]		]
	'''Pregnancy''' is the carrying of one or more ]s or ] by ] ]s, including humans, inside their bodies. In a pregnancy there can be multiple ]s (for example, in the case of ], or ]). Human pregnancy is the most studied of all ].		'''Pregnancy''' is the carrying of one or more ]s or ] by ] ]s, including humans, inside their bodies. In a pregnancy there can be multiple ]s (for example, in the case of ], or ]). Human pregnancy is the most studied of all ].

	Human pregnancy lasts approximately 40 weeks between the time of the last ] and ] (38 weeks from ]). The medical term for a pregnant ] is "'''genetalian'''," just as the medical term for the unborn human is an ] (early weeks) and then "]" (until birth). A woman who is pregnant for the first time is known as a ] or ]: a woman who has never been pregnant is known as a ]; similarly, the terms ], ] and so on are used for the number of times a woman has given birth.		Human pregnancy lasts approximately 40 weeks between the time of the last ] and ] (38 weeks from ]). The medical term for a pregnant ] is "'''genetalian'''," just as the medical term for the unborn human is an ] (early weeks) and then "]" (until birth). A woman who is pregnant for the first time is known as a ] or ]: a woman who has never been pregnant is known as a ]; similarly, the terms ], ] and so on are used for the number of times a woman has given birth.

	In many societies' medical and legal definitions, human pregnancy is arbitrarily divided into three ] periods, as a means to simplify reference to the different stages of fetal development. The first trimester period carries the highest risk of ] (natural death of embryo or fetus), while during the second trimester the development of the fetus can start to be monitored and diagnosed. The third trimester marks the beginning of ], which means the fetus can survive if an early natural or induced birth occurs.		In many societies' medical and legal definitions, human pregnancy is arbitrarily divided into three ] periods, as a means to simplify reference to the different stages of fetal development. The first trimester period carries the highest risk of ] (natural death of embryo or fetus), while during the second trimester the development of the fetus can start to be monitored and diagnosed. The third trimester marks the beginning of ], which means the fetus can survive if an early natural or induced birth occurs. Because of the possible viability of developed fetus, cultural and legal definitions of life often consider a fetus in the third trimester to be a distinct living ]. <!-- make footer reference (Though this can be controversial, depending on the age of the fetus and the discussed context.) -->
	Because of the possible viability of developed fetus, cultural and legal definitions of life often consider a fetus in the third trimester to be a distinct living ]. <!-- make footer reference (Though this can be controversial, depending on the age of the fetus and the discussed context.) -->
	<!-- Out of place: // known medically as a ''spontaneous abortion.'' It is often the result of health problems of the fetus, the mother, or damage caused after conception. -->		<!-- Out of place: // known medically as a ''spontaneous abortion.'' It is often the result of health problems of the fetus, the mother, or damage caused after conception. -->
	:''See also ]		:''See also ]

	== Detection and dating ==		==Detection and dating==
	]		]
	The beginning of pregnancy may be detected in a number of ways, including various pregnancy tests which detect hormones generated by the newly-formed ]. Clinical blood and urine tests can detect pregnancy as early as 6-8 days after date of conception. ]s are personal urine tests, which normally can't detect a pregnancy until at least 12-15 days after conception. Both clinical and home tests can only detect the state of pregnancy, and cannot detect the actual date of conception.		The beginning of pregnancy may be detected in a number of ways, including various pregnancy tests which detect hormones generated by the newly-formed ]. Clinical blood and urine tests can detect pregnancy as early as 6-8 days after date of conception. ]s are personal urine tests, which normally can't detect a pregnancy until at least 12-15 days after conception. Both clinical and home tests can only detect the state of pregnancy, and cannot detect the actual date of conception.
	]		]
	In practice, for the purpose of giving a date for a conception (i.e. an "age" for an ]), doctors typically date the pregnancy by "menstrual date," based on the first day of a woman's last menstrual period, as the woman reports it. Unless a woman's recent ] activity has been limited, the exact date of conception or implantation are unknown. And absent any symptoms of ], the only visible sign of a pregnancy is often an interruption of her normal monthly menstruation cycle, (i.e. a "late period"). Hence, the "menstrual date" is simply a common educated estimate for the age of a fetus, which is an average of two weeks later than conception, (the ] considers 0 to 30 days after last menstruation, hence a 14 day average). The term "conception date" may sometimes be used when that date is more certain, though even medical professionals can be imprecise with their use of the two distinct terms. An unknown date for conception means that in practice the distinction between embryo and fetus is a clinical one only, and not used as to refer to stages of development of a particular pregnancy.		In practice, for the purpose of giving a date for a conception (i.e. an "age" for an ]), doctors typically date the pregnancy by "menstrual date," based on the first day of a woman's last menstrual period, as the woman reports it. Unless a woman's recent ] activity has been limited, the exact date of conception or implantation are unknown. And absent any symptoms of ], the only visible sign of a pregnancy is often an interruption of her normal monthly menstruation cycle, (i.e. a "late period"). Hence, the "menstrual date" is simply a common educated estimate for the age of a fetus, which is an average of two weeks later than conception, (the ] considers 0 to 30 days after last menstruation, hence a 14 day average). The term "conception date" may sometimes be used when that date is more certain, though even medical professionals can be imprecise with their use of the two distinct terms. An unknown date for conception means that in practice the distinction between embryo and fetus is a clinical one only, and not used as to refer to stages of development of a particular pregnancy.
	<!-- Redundant // Ultimately, because pregnancy dating generally comes after at least 2 to 4 weeks of development, and because clinical terms are improper in reference to emerging families, the term "embryo" is generally not used when referring to a particular pregnancy. -->		<!-- Redundant // Ultimately, because pregnancy dating generally comes after at least 2 to 4 weeks of development, and because clinical terms are improper in reference to emerging families, the term "embryo" is generally not used when referring to a particular pregnancy. -->
⚫	]

		⚫	]
	There are likewise finer distinctions between the concepts of fertilization (]) and the actual state of pregnancy. In a normal pregnancy, the ] of the egg usually will have occurred in the ]s or in the ]. (In women with ], an egg may become fertilized yet fail to become implanted in the uterus.) If the pregnancy is the result of ] the fertilization will have occurred in a ], after which "pregnancy" begins when one or more zygotes implants after being transferred by a ] in the woman's uterus.		There are likewise finer distinctions between the concepts of fertilization (]) and the actual state of pregnancy. In a normal pregnancy, the ] of the egg usually will have occurred in the ]s or in the ]. (In women with ], an egg may become fertilized yet fail to become implanted in the uterus.) If the pregnancy is the result of ] the fertilization will have occurred in a ], after which "pregnancy" begins when one or more zygotes implants after being transferred by a ] in the woman's uterus.

	<!-- This may be moved, or commented out, as its a fair point that politics is not the point of the main discussion. -->		<!-- This may be moved, or commented out, as its a fair point that politics is not the point of the main discussion. -->
	In the context of political debates regarding a proper ], the terminology of pregnancy can be confusing. Because precise assessment of a pregnancy as being at the "embryo" or "fetus" stage is usually undeterminable, the terms (though more clinically precise) are less commonly used than terms like "baby" or "child." The medically and politically neutral term which remains is simply "pregnancy," though this can be problematic as it only refers indirectly to the embryo or fetus. In the context of personal treatment, ] generally dictates that doctors make sparse use of clinical language like "fetus" and "embryo," and instead simply refer to the developing child as a "]."		In the context of political debates regarding a proper ], the terminology of pregnancy can be confusing. Because precise assessment of a pregnancy as being at the "embryo" or "fetus" stage is usually undeterminable, the terms (though more clinically precise) are less commonly used than terms like "baby" or "child." The medically and politically neutral term which remains is simply "pregnancy," though this can be problematic as it only refers indirectly to the embryo or fetus. In the context of personal treatment, ] generally dictates that doctors make sparse use of clinical language like "fetus" and "embryo," and instead simply refer to the developing child as a "]."

	<!-- FROM BELOW // Integrate		<!-- FROM BELOW // Integrate

	===Detection===		===Detection===
	The early stages of pregnancy is often discovered by using a ]. In the post-implantation phase the ] secretes a hormone named] which in turn, stimulates the ] in the mother's ovary to continue producing ]. This acts to maintain the lining of the uterus so that the embryo will continue to be nourished. The glands in the lining of the uterus will swell in response to the blastocyst, and capillaries will be stimulated to grow in that region. This allows the blastocyst to receive vital nutrients from the mother. Pregnancy tests detect the presence of human chorionic gonadotropin.		The early stages of pregnancy is often discovered by using a ]. In the post-implantation phase the ] secretes a hormone named] which in turn, stimulates the ] in the mother's ovary to continue producing ]. This acts to maintain the lining of the uterus so that the embryo will continue to be nourished. The glands in the lining of the uterus will swell in response to the blastocyst, and capillaries will be stimulated to grow in that region. This allows the blastocyst to receive vital nutrients from the mother. Pregnancy tests detect the presence of human chorionic gonadotropin.
	-->		-->
	]		]
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	==Timeline of a typical pregnancy==		==Timeline of a typical pregnancy==
	Pregnancy is typically broken into three periods, or trimesters, each of about three months. While there are no hard and fast rules, these distinctions are useful in describing the changes that take place over time.		Pregnancy is typically broken into three periods, or trimesters, each of about three months. While there are no hard and fast rules, these distinctions are useful in describing the changes that take place over time.

	=== First trimester ===
	==== ~~Fertilization =~~===		===First trimester===
			====Fertilization====
	{{main\|Fertilization}}		{{main\|Fertilization}}
	]		]
	]		]

	Before pregnancy begins, a female ] (]) must be fertilized, by male ] in a process referred to in medicine as "fertilization," or commonly as "conception." Pregnancy is usually dated as beginning on the first day of a woman's last menstrual period. This date is used to estimate an EDD, or Estimated Date of Delivery.		Before pregnancy begins, a female ] (]) must be fertilized, by male ] in a process referred to in medicine as "fertilization," or commonly as "conception." Pregnancy is usually dated as beginning on the first day of a woman's last menstrual period. This date is used to estimate an EDD, or Estimated Date of Delivery.

	Traditionally (according to ], which is used to calculate the estimated date of delivery (EDD)), a human pregnancy is considered to last approximately 40 weeks (280 days) from the last menstrual period (LMP), or 37 weeks (259 days) from the date of conception. However, a pregnancy is considered to have reached term between 37 and 43 weeks. Babies born before the 37 week mark are considered ], while babies born after the 43 week mark are considered ].		Traditionally (according to ], which is used to calculate the estimated date of delivery (EDD)), a human pregnancy is considered to last approximately 40 weeks (280 days) from the last menstrual period (LMP), or 37 weeks (259 days) from the date of conception. However, a pregnancy is considered to have reached term between 37 and 43 weeks. Babies born before the 37 week mark are considered ], while babies born after the 43 week mark are considered ].
			]

	] However, the average length of pregnancy depends on ethnic background of the mother (] women are more likely to have a longer pregnancy than other women) and if it is a first pregnancy (which tend to last longer than subsequent pregnancies). For example, a Caucasian woman's first pregnancy lasts an average 274 days from conception (288 days from the last menstrual period){{ref\|1}}.		However, the average length of pregnancy depends on ethnic background of the mother (] women are more likely to have a longer pregnancy than other women) and if it is a first pregnancy (which tend to last longer than subsequent pregnancies). For example, a Caucasian woman's first pregnancy lasts an average 274 days from conception (288 days from the last menstrual period){{ref\|1}}.

	An accurate date of conception is important, because it is used in calculating the results of various ] (for example, in the ]). A decision may be made to ] labour if a baby is perceived to be overdue. Due dates are only a rough estimate, and the process of accurately dating a pregnancy is complicated by the fact that not all women have 28 day menstrual cycles, or ovulate on the 14th day following their last menstrual period. Approximately 3.6% of all mothers deliver on the due date predicted by LMP, and only 4.7% give birth on the day predicted by ultrasound.		An accurate date of conception is important, because it is used in calculating the results of various ] (for example, in the ]). A decision may be made to ] labour if a baby is perceived to be overdue. Due dates are only a rough estimate, and the process of accurately dating a pregnancy is complicated by the fact that not all women have 28 day menstrual cycles, or ovulate on the 14th day following their last menstrual period. Approximately 3.6% of all mothers deliver on the due date predicted by LMP, and only 4.7% give birth on the day predicted by ultrasound.

	==== Implantation ====		====Implantation====
	In medicine, pregnancy is defined as beginning when the developing ] becomes ] into the ] lining of a woman's ]. The outer layers of the embryo grow and form a ], for the purpose of receiving essential ] through the ] wall. The ] in a newborn child signifies the remnants of the connection to the placenta. The developing baby undergoes tremendous growth and changes during the process of ].		In medicine, pregnancy is defined as beginning when the developing ] becomes ] into the ] lining of a woman's ]. The outer layers of the embryo grow and form a ], for the purpose of receiving essential ] through the ] wall. The ] in a newborn child signifies the remnants of the connection to the placenta. The developing baby undergoes tremendous growth and changes during the process of ].

	] aflicts about half of all pregnant women, typically only in the first trimester.		] aflicts about half of all pregnant women, typically only in the first trimester.
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	Final weight gain takes place, and the baby begins to move regularly. This can be uncomfortable, causing symptoms like weak bladder control and back-ache.		Final weight gain takes place, and the baby begins to move regularly. This can be uncomfortable, causing symptoms like weak bladder control and back-ache.

	== Medical aspects of pregnancy ==		==Medical aspects of pregnancy==
	{{Main\|Obstetrics}}		{{Main\|Obstetrics}}

	Diagnostic criteria are: In a woman who has regular menstrual cycles and is sexually active, a period delayed by a few days or weeks is suggestive of pregnancy; elevated B-hcG to around 100,000 mIU/mL by 10 weeks of gestation.		Diagnostic criteria are: In a woman who has regular menstrual cycles and is sexually active, a period delayed by a few days or weeks is suggestive of pregnancy; elevated B-hcG to around 100,000 mIU/mL by 10 weeks of gestation.

	== Birth ==		==Birth==
	]		]
	{{main\|Childbirth}}		{{main\|Childbirth}}

	Childbirth is the process in which the baby is born. It is considered by many to be the beginning of a person's life, where age is defined relative to this event in most cultures.		Childbirth is the process in which the baby is born. It is considered by many to be the beginning of a person's life, where age is defined relative to this event in most cultures.

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	==Postnatal Period==		==Postnatal Period==
	{{main\|Postnatal}}		{{main\|Postnatal}}

	For topics following on from a successful pregnancy and birth, see:		For topics following on from a successful pregnancy and birth, see:
	* ]		* ]
	* ]		* ]

	== Terms and definitions ==		==Terms and definitions==
		⚫	===Technical===

⚫	=== Technical ===
	* ''zygote'' - from fertilization until second cell division		* ''zygote'' - from fertilization until second cell division
	* ''embryo'' - conceptus between time of fertilization to 10 weeks of gestation		* ''embryo'' - conceptus between time of fertilization to 10 weeks of gestation
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	* ''Ga Pw-x-y-z'' - a = number of pregnancies, w = number of term births, x = number of preterm births, y = number of miscarriages, z = number of living children; for example, G4P1-2-1-3 means the woman had a total of 4 pregnancies, of which 1 is of term, 2 are preterm, 1 miscarriage, and 3 total living children (1 term + 2 preterm).		* ''Ga Pw-x-y-z'' - a = number of pregnancies, w = number of term births, x = number of preterm births, y = number of miscarriages, z = number of living children; for example, G4P1-2-1-3 means the woman had a total of 4 pregnancies, of which 1 is of term, 2 are preterm, 1 miscarriage, and 3 total living children (1 term + 2 preterm).

	=== Colloquial ===		===Colloquial===
	There are a number of colloquialisms for pregnancy, usually regional. The action of impregnating a woman or girl is called 'knocking (her) up' in Canada and some parts of the U.S., and the state of being pregnant 'knocked-up'. The term 'lady-in-waiting', meaning a pregnant mother, is used broadly in the U.S. The word 'gone' or 'along' is used to represent gestational time, e.g. 'she's really far gone' or 'about 6 weeks gone' or 'six months along'. In the southern U.S. the euphemism of a water ] is occasionally used to represent pregnancy (e.g. 'drink out of the well', to become pregnant), and a baby almost ready to be delivered is 'on his/her road'. Eastern Seaboard slang describes the mother as being 'in a fix' or, occasionally, 'preggers'; the Southern U.S. equivalent is 'in the family way'. An alternate term not slang or colloquial is 'with child', now restricted mainly to England. 'Having a bun in the oven' is another frequently used phrase to indicate that a woman is pregnant.		There are a number of colloquialisms for pregnancy, usually regional. The action of impregnating a woman or girl is called 'knocking (her) up' in Canada and some parts of the U.S., and the state of being pregnant 'knocked-up'. The term 'lady-in-waiting', meaning a pregnant mother, is used broadly in the U.S. The word 'gone' or 'along' is used to represent gestational time, e.g. 'she's really far gone' or 'about 6 weeks gone' or 'six months along'. In the southern U.S. the euphemism of a water ] is occasionally used to represent pregnancy (e.g. 'drink out of the well', to become pregnant), and a baby almost ready to be delivered is 'on his/her road'. Eastern Seaboard slang describes the mother as being 'in a fix' or, occasionally, 'preggers'; the Southern U.S. equivalent is 'in the family way'. An alternate term not slang or colloquial is 'with child', now restricted mainly to England. 'Having a bun in the oven' is another frequently used phrase to indicate that a woman is pregnant.

	==See also==		==See also==
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	* ]		* ]

	== Reference ==		==Reference==
	* {{note\|1}} Mittendorf R, Williams MA, Berkey CS, Cotter PF. ''The length of uncomplicated human gestation.'' Obstet Gynecol 1990;75:929-32. PMID 2342739.		* {{note\|1}} Mittendorf R, Williams MA, Berkey CS, Cotter PF. ''The length of uncomplicated human gestation.'' Obstet Gynecol 1990;75:929-32. PMID 2342739.

	== External links ==		==External links==
	*		*
	*		*
	*		*
	*		*
	*		*
	*		*
	*] [http://www.agi-usa.org/pubs/tgr/08/2/gr080207.html (2005) ''The Implications of Defining When a Woman Is Pregnant'' discussion of the political and legal background.		* ] [http://www.agi-usa.org/pubs/tgr/08/2/gr080207.html (2005) ''The Implications of Defining When a Woman Is Pregnant'' discussion of the political and legal background.

	]		]

Revision as of 19:59, 31 December 2005

For a broader view of pregnancy in mammals see mammalian pregnancy. For the medicine of pregnancy, see Obstetrics.

File:Pregnancy.gif

Pregnancy

Pregnancy is the carrying of one or more embryos or fetuses by female mammals, including humans, inside their bodies. In a pregnancy there can be multiple gestations (for example, in the case of twins, or triplets). Human pregnancy is the most studied of all mammalian pregnancies. Human pregnancy lasts approximately 40 weeks between the time of the last menstrual cycle and birth (38 weeks from fertilisation). The medical term for a pregnant woman is "genetalian," just as the medical term for the unborn human is an embryo (early weeks) and then "foetus" (until birth). A woman who is pregnant for the first time is known as a primigravida or gravida 1: a woman who has never been pregnant is known as a gravida 0; similarly, the terms para 0, para 1 and so on are used for the number of times a woman has given birth.

In many societies' medical and legal definitions, human pregnancy is arbitrarily divided into three trimester periods, as a means to simplify reference to the different stages of fetal development. The first trimester period carries the highest risk of miscarriage (natural death of embryo or fetus), while during the second trimester the development of the fetus can start to be monitored and diagnosed. The third trimester marks the beginning of viability, which means the fetus can survive if an early natural or induced birth occurs. Because of the possible viability of developed fetus, cultural and legal definitions of life often consider a fetus in the third trimester to be a distinct living person.

See also Pregnancy terms and definitions

Detection and dating

File:Illustration fertilized egg.jpg

A blastocyst.

The beginning of pregnancy may be detected in a number of ways, including various pregnancy tests which detect hormones generated by the newly-formed placenta. Clinical blood and urine tests can detect pregnancy as early as 6-8 days after date of conception. Home pregnancy tests are personal urine tests, which normally can't detect a pregnancy until at least 12-15 days after conception. Both clinical and home tests can only detect the state of pregnancy, and cannot detect the actual date of conception.

File:Illustration embryo.jpg

A human embryo, two weeks after implantation.

In practice, for the purpose of giving a date for a conception (i.e. an "age" for an embryo), doctors typically date the pregnancy by "menstrual date," based on the first day of a woman's last menstrual period, as the woman reports it. Unless a woman's recent sexual activity has been limited, the exact date of conception or implantation are unknown. And absent any symptoms of morning sickness, the only visible sign of a pregnancy is often an interruption of her normal monthly menstruation cycle, (i.e. a "late period"). Hence, the "menstrual date" is simply a common educated estimate for the age of a fetus, which is an average of two weeks later than conception, (the margin of error considers 0 to 30 days after last menstruation, hence a 14 day average). The term "conception date" may sometimes be used when that date is more certain, though even medical professionals can be imprecise with their use of the two distinct terms. An unknown date for conception means that in practice the distinction between embryo and fetus is a clinical one only, and not used as to refer to stages of development of a particular pregnancy.

There are likewise finer distinctions between the concepts of fertilization (conception) and the actual state of pregnancy. In a normal pregnancy, the fertilization of the egg usually will have occurred in the Fallopian tubes or in the uterus. (In women with fertility problems, an egg may become fertilized yet fail to become implanted in the uterus.) If the pregnancy is the result of in-vitro fertilization the fertilization will have occurred in a Petri dish, after which "pregnancy" begins when one or more zygotes implants after being transferred by a physician in the woman's uterus.

In the context of political debates regarding a proper definition of life, the terminology of pregnancy can be confusing. Because precise assessment of a pregnancy as being at the "embryo" or "fetus" stage is usually undeterminable, the terms (though more clinically precise) are less commonly used than terms like "baby" or "child." The medically and politically neutral term which remains is simply "pregnancy," though this can be problematic as it only refers indirectly to the embryo or fetus. In the context of personal treatment, bedside manner generally dictates that doctors make sparse use of clinical language like "fetus" and "embryo," and instead simply refer to the developing child as a "baby."

File:Nine months slides.jpg

A timeline of pregnancy

Timeline of a typical pregnancy

Pregnancy is typically broken into three periods, or trimesters, each of about three months. While there are no hard and fast rules, these distinctions are useful in describing the changes that take place over time.

First trimester

Fertilization

Main article: Fertilization

File:Conception C sm2.jpg

Conception (fertilization).

File:Conception B sm2.jpg

Implantation.

Before pregnancy begins, a female oocyte (egg) must be fertilized, by male sperm in a process referred to in medicine as "fertilization," or commonly as "conception." Pregnancy is usually dated as beginning on the first day of a woman's last menstrual period. This date is used to estimate an EDD, or Estimated Date of Delivery.

Traditionally (according to Naegele's Rule, which is used to calculate the estimated date of delivery (EDD)), a human pregnancy is considered to last approximately 40 weeks (280 days) from the last menstrual period (LMP), or 37 weeks (259 days) from the date of conception. However, a pregnancy is considered to have reached term between 37 and 43 weeks. Babies born before the 37 week mark are considered premature, while babies born after the 43 week mark are considered postmature.

File:Month 1 sm.jpg

First month of pregnancy.

However, the average length of pregnancy depends on ethnic background of the mother (Caucasian women are more likely to have a longer pregnancy than other women) and if it is a first pregnancy (which tend to last longer than subsequent pregnancies). For example, a Caucasian woman's first pregnancy lasts an average 274 days from conception (288 days from the last menstrual period).

An accurate date of conception is important, because it is used in calculating the results of various prenatal tests (for example, in the triple screen test). A decision may be made to induce labour if a baby is perceived to be overdue. Due dates are only a rough estimate, and the process of accurately dating a pregnancy is complicated by the fact that not all women have 28 day menstrual cycles, or ovulate on the 14th day following their last menstrual period. Approximately 3.6% of all mothers deliver on the due date predicted by LMP, and only 4.7% give birth on the day predicted by ultrasound.

Implantation

In medicine, pregnancy is defined as beginning when the developing embryo becomes implanted into the endometrial lining of a woman's uterus. The outer layers of the embryo grow and form a placenta, for the purpose of receiving essential nutrients through the uterus wall. The umbilical cord in a newborn child signifies the remnants of the connection to the placenta. The developing baby undergoes tremendous growth and changes during the process of embryonic and fetal development.

Morning sickness aflicts about half of all pregnant women, typically only in the first trimester.

Second trimester

File:Judithpregnant.jpg

Most women feel more energised in this period, and begin to seriously put on weight. The first movement of the baby, often referred to as "quickening", can be felt, as the baby begins to form into a recognisable shape.

Third trimester

Final weight gain takes place, and the baby begins to move regularly. This can be uncomfortable, causing symptoms like weak bladder control and back-ache.

Medical aspects of pregnancy

Main article: Obstetrics

Diagnostic criteria are: In a woman who has regular menstrual cycles and is sexually active, a period delayed by a few days or weeks is suggestive of pregnancy; elevated B-hcG to around 100,000 mIU/mL by 10 weeks of gestation.

Birth

File:Birth Process.jpg

Stages of birth process.

Main article: Childbirth

Childbirth is the process in which the baby is born. It is considered by many to be the beginning of a person's life, where age is defined relative to this event in most cultures.

A woman is considered to be in labour when she begins experiencing regular painful uterine contractions, accompanied by changes of her cervix — primarily effacement and dilation. While childbirth is widely experienced as painful, some women do report painless labours.

Postnatal Period

Main article: Postnatal

For topics following on from a successful pregnancy and birth, see:

Terms and definitions

Technical

zygote - from fertilization until second cell division
embryo - conceptus between time of fertilization to 10 weeks of gestation
fetus - from 10 weeks of gestation to time of birth
FASD - Fetal Alcohol Spectrum Disorder, a clinical term for the effects alcohol can have on the developing fetus
gestational age - time from last menstrual period (LMP) up to present
gravidity (G) - number of times a woman has been pregnant

infant - time of birth to 1 year of age
viability - minimum age for fetus survival, ca. third trimester

previable infant - delivered prior to 24 weeks
preterm infant - delivered between 24-37 weeks
term infant - delivered between 37-42 weeks

first trimester - up to 14 weeks of gestation
second trimester - 14 to 28 weeks of gestation
third trimester - 28 weeks to delivery

parity (P) - number of pregnancies with a birth beyond 20 weeks GA or an infant weighing more than 500 g
Ga Pw-x-y-z - a = number of pregnancies, w = number of term births, x = number of preterm births, y = number of miscarriages, z = number of living children; for example, G4P1-2-1-3 means the woman had a total of 4 pregnancies, of which 1 is of term, 2 are preterm, 1 miscarriage, and 3 total living children (1 term + 2 preterm).

Colloquial

There are a number of colloquialisms for pregnancy, usually regional. The action of impregnating a woman or girl is called 'knocking (her) up' in Canada and some parts of the U.S., and the state of being pregnant 'knocked-up'. The term 'lady-in-waiting', meaning a pregnant mother, is used broadly in the U.S. The word 'gone' or 'along' is used to represent gestational time, e.g. 'she's really far gone' or 'about 6 weeks gone' or 'six months along'. In the southern U.S. the euphemism of a water well is occasionally used to represent pregnancy (e.g. 'drink out of the well', to become pregnant), and a baby almost ready to be delivered is 'on his/her road'. Eastern Seaboard slang describes the mother as being 'in a fix' or, occasionally, 'preggers'; the Southern U.S. equivalent is 'in the family way'. An alternate term not slang or colloquial is 'with child', now restricted mainly to England. 'Having a bun in the oven' is another frequently used phrase to indicate that a woman is pregnant.

Reference

Mittendorf R, Williams MA, Berkey CS, Cotter PF. The length of uncomplicated human gestation. Obstet Gynecol 1990;75:929-32. PMID 2342739.

External links

Home Pregnancy Test and Stages
BabyCenter has an extensive library of articles on pregnancy and childbirth
Early pregnancy: Morning sickness, fatigue and other common symptoms, from MayoClinic.com
Pregnancy Conception Overview FAQs
The visible embryo
Normal Pregnancy, Labor, And Delivery (Merck Manual)
Alan Guttmacher Institute [http://www.agi-usa.org/pubs/tgr/08/2/gr080207.html (2005) The Implications of Defining When a Woman Is Pregnant discussion of the political and legal background.

Category:

Pregnancy