Beginning of pregnancy may be detected in a number of different ways, either by a pregnant woman without medical testing, or by using medical tests with or without the assistance of a medical professional.
Most pregnant women experience a number of symptoms , which can signify pregnancy. The symptoms can include nausea and vomiting, excessive tiredness and fatigue, craving for certain foods not normally considered a favorite, and frequent urination particularly during the night.
A number of early medical signs are associated with pregnancy. These signs typically appear, if at all, within the first few weeks after conception. Although not all of these signs are universally present, nor are all of them diagnostic by themselves, taken together they make a presumptive diagnosis of pregnancy. These signs include the presence of human chorionic gonadotropin (hCG) in the blood and urine, missed menstrual period, implantation bleeding that occurs at implantation of the embryo in the uterus during the third or fourth week after last menstrual period, increased basal body temperature sustained for over 2 weeks after ovulation, Chadwick's sign (darkening of the cervix, vagina, and vulva), Goodell's sign (softening of the vaginal portion of the cervix), Hegar's sign (softening of the uterus isthmus), and pigmentation of linea alba – Linea nigra, (darkening of the skin in a midline of the abdomen, caused by hyperpigmentation resulting from hormonal changes, usually appearing around the middle of pregnancy).
Pregnancy detection can be accomplished using one or more various pregnancy tests, which detect hormones generated by the newly formed placenta. Clinical blood and urine tests can detect pregnancy 12 days after implantation , which is as early as 6 to 8 days after fertilization. Blood pregnancy tests are more accurate than urine tests.[26] Home pregnancy tests are personal urine tests, which normally cannot detect a pregnancy until at least 12 to 15 days after fertilization. Both clinical and home tests can only detect the state of pregnancy, and cannot detect the date the embryo was conceived.
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.
Despite all the signs, some women may not realize they are pregnant until they are quite far along in their pregnancy. In some cases, a few woman have not been aware of their pregnancy until they begin labour. This can be caused by many factors, including irregular periods (quite common in teenagers), certain medications (not related to conceiving children), and obese women who disregard their weight gain. Others may be in denial of their situation.
An early sonograph can determine the age of the pregnancy fairly accurately. In practice, doctors typically express the age of a pregnancy (i.e., an "age" for an embryo) in terms of "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, she has been charting her cycles, or the conception is the result of some types of fertility treatment (such as IUI or IVF), the exact date of fertilization is unknown. Without symptoms such as morning sickness, often the only visible sign of a pregnancy is an interruption of the woman's 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 2 weeks later than the first day of the woman's last menstrual period. 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. The due date can be calculated by using Naegele's rule. The expected date of delivery may also be calculated from sonogram measurement of the fetus. This method is slightly more accurate than methods based on LMP.
Diagnostic criteria are: Women who have menstrual cycles and are 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.
A Pregnancy is the carrying of one or more offspring, known as a fetus or embryo, inside the womb of a female. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets.
Childbirth usually occurs about 38 weeks after conception; i.e., approximately 40 weeks from the last normal menstrual period (LNMP) in humans. The World Health Organization defines normal term for delivery as between 37 weeks and 42 weeks.
Pregnancy occurs as the result of the female gamete or oocyte merging with the male gamete, spermatozoon, in a process referred to, in medicine, as fertilization, or more commonly known as "conception". After the point of fertilization, it is referred to as a zygote or fertilized egg. The fusion of male and female gametes usually occurs through the act of sexual intercourse, resulting in spontaneous pregnancy. However, the advent of artificial insemination and in vitro fertilisation have also made achieving pregnancy possible in cases where sexual intercourse does not result in fertilization (e.g., through choice or male/female infertility).
The process of fertilization occurs in more than a single step, and the interruption of any of these can lead to a failure. Therefore, what is commonly known as "conception" is much more than the fusion between the female gamete and male spermatozoon. Through fertilization, the egg and sperm are saved: the egg is activated to begin its developmental program, and the haploid nuclei of the two gametes come together to form the genome of a new diploid organism.
At the very beginning of the process, the sperm undergoes a series of changes which makes pregnancy likely to occur. As freshly ejaculated sperm is unable or poorly able to fertilize [10], the sperm undergoes the phenomenon called capacitation. It is estimated that during the ejaculation, 300,000,000 sperma is released, from which only 200 reach the oviduct. Capacitation is the process through which the spermatozoon is prepared for the merging with the egg. Capacitation occurs in 5 to 6 hours and it takes place once the sperm reaches the vagina. This is also the process through which the spermatozoon becomes hyperactivated and prepared for the acrosome reaction. In order to be able to fecundate the egg, the sperm must get through the coat surrounding the egg, the so called "zona pellucida". Once zona pellucida is penetrated, the sperm is able to reach the oocyte. But in order to get through the egg's coat, the sperm undergoes an acrosome reaction that provides it with and enzymatic drill which is able to penetrate zona pellucida. The acrosome itself is a modified lysosome, situated on the anterior part of the head of the sperm.
Once a sperm penetrates the zona pellucida, it binds to and fuses with the plasma membrane of the oocyte. Binding occurs at the posterior (post-acrosomal) region of the sperm head. After binding occurs, the egg must also undergo a series of metabolic and physical changes which may influence the further development of the zygote. These changes are called in medicine egg activation, mainly because prior to fertilization, the egg is in a latent state.
Methods to assist reproduction also include intracytoplasmic sperm injection, gamete intrafallopian transfer (GIFT), zygote intrafallopian transfer (ZIFT), and embryo cryopreservation (frozen fertilized egg and sperm). These techniques are considered as alternatives to get pregnant by women who have tried unsuccessfully for at least one year. It is estimated that in the United States, more than 6 million adults , or 10% of the adult population, are affected by infertility.
Bronchitis on baby & child
The Symptoms
Your toddler may first have cold symptoms, like a sore throat, fatigue, a runny nose, chills, aches, and a slight fever (100 to 101 degrees F). He'll develop a cough, which often starts out dry and unproductive but winds up producing greenish or yellowish mucus. He may gag or vomit while coughing.
Your toddler's chest may hurt, he may feel short of breath, and he may wheeze. If the bronchitis is severe, his fever may climb for a few days, and his cough may linger for several weeks as the bronchi heal.
Some people — almost always adults who smoke or children who live with smokers — suffer from bronchitis symptoms for months at a time. This is called chronic bronchitis (as opposed to infectious or acute bronchitis), and it's one excellent reason to keep cigarettes out of your house.
Bronchitis
Bronchitis is an infection or inflammation of the large air passages to the lungs. (These airways are called bronchi.) When your toddler has a cold, sore throat, flu, or sinus infection, the virus that caused the misery can spread to the bronchi. Once the germs take hold there, the airways become swollen, inflamed, and partly blocked with mucus. While bacterial infections and irritants such as cigarette smoke, fumes, and dust can trigger bronchitis, viruses are the most common culprits in children.