RedWine
05-14-2007, 04:27 AM
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.
Childbirth usually occurs about 38 weeks from fertilization, i.e. approximately 40 weeks from the start of the last menstruation. Thus, pregnancy lasts about nine months, although the exact definition of the English word “pregnancy” is a subject of controversy. The medical term for a pregnant female human is genetalian, although this term is rarely used in common speech. The term embryo is used to describe the developing human during the initial weeks, and the term fetus is used from about two months of development until birth. A woman who is pregnant for the first time is known as a primigravida or "gravida 1", while a woman who has never been pregnant is known as "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 somewhat 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). During the second trimester the development of the fetus can start to be monitored and diagnosed. The third trimester marks the beginning of viability, or the ability of the fetus to survive, with or without medical help, outside of the mother's womb.
Pregnancy symptoms
Symptoms of pregnancy may vary from woman to woman and even pregnancy to pregnancy. While not all will occur with every pregnancy and some symptoms are in fact rare, following is a list of some of the potential symptoms of pregnancy.
Implantation, the female body begins to adjust to prenatal stage. There may be some twinge associated with implantation. (Generally 7-10 after fertilization.)
Delayed or difference in menstruation.
Minor vaginal bleeding (spotting).
Swollen or tender breast, minor lactation in third trimester.
Fatigue, also may experience sleeplessness.
Nausea, sometimes accompanied by vomiting, esp. the first trimester, most likely to start at around 7 weeks. (morning sickness).
Lower backaches, but few pregnant women have serious back pain.
Headaches, some may reach migraine level in others.
Long frequent hiccuping spells.
Enlarged feet and hands, or expanded buttocks.
Frequent urination, sometimes random "drips" of urine.
Constipation, but a few encounter random defecation.
Food cravings, or increased appetite.
Rational fear of increasingly imposing burden.
Heartburn or upset stomach, but rarely may accompany vomiting.
Stomach/intestinal gas, may be frequently flatulent or belch.
Difficulty in walking and balance, some may be put on bedrest.
Difficulty with contact or vision prescriptions.
Symptoms of pregnancy do not allow for a pregnancy diagnosis because each of these symptoms has the potential to be explained by other reasons (e.g. missing a period because of stress).
Pregnancy does have a minor, but noticed psychological effect by hormonal changes and chemical reactions in some women, known as "mood swings" that are controlled. Pregnant woman may experience periods of enhanced content, excitement or fickleness, and melancholy, anxiety or angst, but it often depends on how the woman views herself and attitudes on her condition in various ways.
Childbirth is the process by which an infant is born. It is considered by many to be the beginning of a person's life, and age is defined relative to this event in most cultures.
A woman is considered to be in labour when she begins experiencing regular 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, while others find that concentrating on the birth helps to quicken labour and lessen the sensations. Most women are capable of having a normal birth but sometimes complications arise and a woman may need to undergo a caesarean section.
During the time immediately after birth, both baby and mother are hormonally cued to bond, the mother through the release of oxytocin,a hormone also released during breastfeeding.
Detection
The early stages of pregnancy are often discovered by using a pregnancy test, as soon as 48 hours after fertilization using sophisticated testing methods, but not until six to twelve days after fertilization using more typical methods. In the post-implantation phase the blastocyst secretes a hormone named human chorionic gonadotropin which in turn, stimulates the corpus luteum in the woman's ovary to continue producing progesterone. 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 woman. Pregnancy tests typically detect the presence of human chorionic gonadotropin.
Childbirth usually occurs about 38 weeks from fertilization, i.e. approximately 40 weeks from the start of the last menstruation. Thus, pregnancy lasts about nine months, although the exact definition of the English word “pregnancy” is a subject of controversy. The medical term for a pregnant female human is genetalian, although this term is rarely used in common speech. The term embryo is used to describe the developing human during the initial weeks, and the term fetus is used from about two months of development until birth. A woman who is pregnant for the first time is known as a primigravida or "gravida 1", while a woman who has never been pregnant is known as "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 somewhat 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). During the second trimester the development of the fetus can start to be monitored and diagnosed. The third trimester marks the beginning of viability, or the ability of the fetus to survive, with or without medical help, outside of the mother's womb.
Pregnancy symptoms
Symptoms of pregnancy may vary from woman to woman and even pregnancy to pregnancy. While not all will occur with every pregnancy and some symptoms are in fact rare, following is a list of some of the potential symptoms of pregnancy.
Implantation, the female body begins to adjust to prenatal stage. There may be some twinge associated with implantation. (Generally 7-10 after fertilization.)
Delayed or difference in menstruation.
Minor vaginal bleeding (spotting).
Swollen or tender breast, minor lactation in third trimester.
Fatigue, also may experience sleeplessness.
Nausea, sometimes accompanied by vomiting, esp. the first trimester, most likely to start at around 7 weeks. (morning sickness).
Lower backaches, but few pregnant women have serious back pain.
Headaches, some may reach migraine level in others.
Long frequent hiccuping spells.
Enlarged feet and hands, or expanded buttocks.
Frequent urination, sometimes random "drips" of urine.
Constipation, but a few encounter random defecation.
Food cravings, or increased appetite.
Rational fear of increasingly imposing burden.
Heartburn or upset stomach, but rarely may accompany vomiting.
Stomach/intestinal gas, may be frequently flatulent or belch.
Difficulty in walking and balance, some may be put on bedrest.
Difficulty with contact or vision prescriptions.
Symptoms of pregnancy do not allow for a pregnancy diagnosis because each of these symptoms has the potential to be explained by other reasons (e.g. missing a period because of stress).
Pregnancy does have a minor, but noticed psychological effect by hormonal changes and chemical reactions in some women, known as "mood swings" that are controlled. Pregnant woman may experience periods of enhanced content, excitement or fickleness, and melancholy, anxiety or angst, but it often depends on how the woman views herself and attitudes on her condition in various ways.
Childbirth is the process by which an infant is born. It is considered by many to be the beginning of a person's life, and age is defined relative to this event in most cultures.
A woman is considered to be in labour when she begins experiencing regular 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, while others find that concentrating on the birth helps to quicken labour and lessen the sensations. Most women are capable of having a normal birth but sometimes complications arise and a woman may need to undergo a caesarean section.
During the time immediately after birth, both baby and mother are hormonally cued to bond, the mother through the release of oxytocin,a hormone also released during breastfeeding.
Detection
The early stages of pregnancy are often discovered by using a pregnancy test, as soon as 48 hours after fertilization using sophisticated testing methods, but not until six to twelve days after fertilization using more typical methods. In the post-implantation phase the blastocyst secretes a hormone named human chorionic gonadotropin which in turn, stimulates the corpus luteum in the woman's ovary to continue producing progesterone. 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 woman. Pregnancy tests typically detect the presence of human chorionic gonadotropin.