Pregnancy is not a disease but is the process of carrying one or more fetus or embryo inside the uterus of a female. It is also called graviditas. In humans, childbirth occurs about 38 weeks after conception (fertilization of the ovary) and approximately 40 weeks from the last normal menstrual period (LNMP). Thus, pregnancy is the gestation period between conception and childbirth lasting for about nine months. Obstetrics is the surgical field that studies and cares for high risk pregnancy. Midwifery is the field that cares for pregnancy and pregnant women who do not need surgical procedure at childbirth.
Symptoms of Pregnancy
After conception, a woman’s body undergoes a lot of changes both in the physiological and homeostatic mechanisms to ensure the fetus is provided for. They can be categorized as follows:
A) Physiological symptoms:
Morning sickness – vomiting bouts early in the morning is common.
Missed menstrual cycle(s) is another obvious sign of pregnancy.
B) Muscular and skeletal symptoms:
1) Reproductive organs and fetus expand in the gestation period, resulting in weight gain. This enables the necessary increased blood volume and water retention.
2) The body posture changes – the pelvis tilts and the back arches to keep balance because the uterus expands as the baby grows.
3) The gait changes because the lower back the muscles contract to maintain proper alignment and balance.
4) The woman’s foot grows by about half its normal size for balance and to carry additional weight.
5) To increase laxity and elasticity, some skeletal joints widen.
C) Cardiovascular symptoms:
1) Blood volume increases by 40% in the first two trimesters.
2) Increased plasma leads to higher levels of aldosterone and progesterone hormone levels. This suppresses the hypothalamic axis and subsequent menstrual cycle.
3) Higher erythropoietin levels cause the red blood cells to increase in number.
4) Increased breathing and cardiac output is another symptom.
5) Blood pressure fluctuates.
D) Respiratory symptoms:
1) Functional capacity of the respiratory organs decreases as the uterus expands and pushes the diaphragm.
2) Progesterone rests the set point to a lower pressure of carbon dioxide to maintain higher respiration rate at this lower level of carbon dioxide.
E) Metabolic symptoms:
1) The increased steroid hormones, lactogen and cortisol cause the increased and concentrated supply of nutrients for fetal growth and fat deposition.
2) The woman’s resistance to insulin increases.
3) The liver increases gluconeogenesis to increase the maternal glucose levels for the fetus.
F) Other changes:
1) Prolactin levels increase due to maternal pituitary gland enlargement by 50%.
2) Parathyroid hormone is increased due to increases of calcium uptake in the gut and re-absorption by the kidney.
3) Adrenal hormones such as cortisol and aldosterone also increase.
4) Placenta produces lactogen for use of the fetus.
5) Placenta also stimulates lipolysis and fatty acid metabolism by the mother to conserve glucose for the fetus.
6) The maternal tissue’s sensitivity to insulin is also much lower during gestation.
Diagnosis of Pregnancy
Prior to testing for pregnancy, the gynecologist will query about the missed menstrual period and how many cycles were missed to calculate the approximate date of conception and age of the fetus if pregnancy is confirmed.
Physical examination: A physical examination to check for darkening of the cervix, vagina and vulva; softening of the uterus isthmus (vaginal portion of the cervix) are undertaken.
Clinical blood and urine tests: Urine tests and clinical blood tests can detect pregnancy as early as 6-8 days after conception. Blood pregnancy tests are more accurate then urine tests. Home pregnancy tests kits are available but these can detect a pregnancy only 12-15 days after conception.
Ultrasound: Modern 3D ultrasound images provide great details for prenatal diagnosis. A sonograph can determine the fetal age fairly accurately. This shows the fetal image and movements. One can also detect the organs, fingers and toes, etc on a Sonograph.
Causes of Pregnancy
In simple terms, pregnancy denotes the fertilization of the female ovary by the male sperm in the semen as a result of sexual intercourse. Scientifically speaking, it occurs due to penetration of the female gamete (ovary or egg) by the male gamete spermatozoon and is referred to as conception. Pregnancy can also occur due to in vitro-fertilization and this method is used in cases of infertility.
Types of Pregnancy
Pregnancy does not have different types, but it does have different stages since the gestation period is as long as nine months. Various physical and physiological changes take place in the pregnant woman during this long, child-bearing period.
First trimester (Embryonic stage): The first stage is the embryonic stage which lasts for about 8 weeks. At this point, the fetal stage begins and at this point the fetus is as tiny as 1.2 inches in length. This is a very critical stage where a lot of care needs to be taken. Any over-exertion or misadventure can cause a miscarriage and loss of the fetus. The outer layers of the embryo grow and form a placenta, for the purpose of receiving essential nutrients through the uterine wall, or endometrium. The umbilical cord in a newborn child consists of the remnants of the connection to the placenta.
The developing embryo undergoes tremendous growth and all major structures including hands, feet, head, brain and other organs begin to develop and grow in this phase. Also, brain activity is first detected between the 5th and 6th week in this phase. This is still considered primitive neural activity rather than the beginning of the thinking process, which develops much later. It is only after the 23rd week the fetus has developed a sustainable human brain and can survive outside of the womb.
Second trimester: This is the 4th month to 6th month of gestation period. The woman is more energetic and puts on more weight in this phase. The symptom of morning sickness also fades away. Although the fetus starts growing in the first stage, the first movements of the fetus (also called quickening) are felt in the second trimester. The placenta is now fully functioning and the fetus is making insulin and urinating. The reproductive organs of the fetus can now be recognized and one can distinguish it as male or female in this phase.
Third trimester (final stage): In this phase, the fetus grows very rapidly, gaining weight by almost 28gms per day as this is the final weight gain. The woman’s belly appears drooping and heavy. The fetus also moves and turns regularly and the movement can be felt easily. Sometimes this can become quite disruptive and strong to the woman and can cause pain if it is near the woman’s ribs and spine. This phase is a little uncomfortable for the woman, not only because of problems related to posture and weight, but also because of symptoms like weak bladder control and backache. If during this period, a baby is born prematurely, it has chances of survival because its brain and body functions are prepared for ex-utero viability.
Treatment of Pregnancy
As pregnancy is not a disease the treatment would actually involve the care woman needs to take in order to carry the fetus through its full term of nine months and ensure safe childbirth.
Additional Nutrition: Balancing carbohydrates, fat, and proteins and eating a variety of fruits and vegetables, usually ensures good nutrition for anyone. But this is specially so in pregnant women because they are eating for themselves and the growing fetus. Professional and specific dietary advice is essential for those pregnant women whose diets are affected by health issues, religious beliefs etc. Nutrients rich in calcium and vitamin D are also necessary for the development of fetal bones. Foods rich in folic acid, vitamin B9 (to avoid fetal defects), and legumes to keep the digestive system clean are also essential.
Deliberate weight gain: For the proper development of the fetus, the total caloric intake must be increased. The amount of weight gained during pregnancy varies among woman to woman. But, The National Health Service recommends that overall weight gain during the 9-month gestation period for women who start pregnancy at normal weight should ideally be 10 to 12 kg. Being either underweight or overweight in pregnancy can undermine the health of the fetus. Those who are anorexic or obese should consume a diet prescribed by the healthcare professional so as not to undermine the health of either mother or child.
Living with Pregnancy
Pregnancy inhibits normal life to a large extent. For example, in the initial stages there might be signs of weakness and morning sickness. In the later stages there is a lot of weight gain causing slowed movements, constant hunger, etc.
Sometimes certain symptoms may develop which cause discomfort during pregnancy like constipation, persistent vomiting and nausea, backache, heartburn and acidity, dizziness, edema in the feet, varicose veins, etc. These have to be dealt with as per the severity of the symptoms.
Sexual intercourse is not taboo during pregnancy. During pregnancy, the baby is protected from penetrative thrusting by the amniotic fluid in the womb and by the woman’s. In fact, studies show that exposure to semen can increase the natural immunity of a pregnant woman. Secondly, the regular expansion of the cervix during intercourse makes childbirth less uncomfortable for the woman, but due care needs to be taken to prevent a miscarriage, especially in the first phase of pregnancy. Sex has to be avoided only if the attending physician feels that there are other complications and is vital for the survival of the fetus and health of the mother.
Prevention of Pregnancy
Measure taken to prevent conception and pregnancy are called birth control measures or contraceptive measures. This can be in the form of actions, devices or medications to deliberately prevent pregnancy.
Behavioral methods: The frequency and timings of the intercourse within the menstrual cycle of the woman are coordinated by the couple in order to prevent pregnancy.
Coitus interruptus: The oldest method of preventing pregnancy is the interruption of the intercourse just before male ejaculation so that the semen does not enter the woman’s vagina and hence the sperms do not reach the ovaries.
Oral contraceptives: Use of contraceptives is very ancient. Even the Ancient Egyptian set of instructions on creating a contraceptive pessary. Today there are various pills easily available commercially which are very good contraceptives and can prevent unwanted pregnancies.
Condoms: This is an external barrier method of contraception which prevents the sperm entering the female reproductive tract. Condoms are made of latex or polyurethane and are medically safe for use. Different condoms are available for both male and female use.
Hormonal method: Hormonal emergency contraceptives, also known as the morning-after-pill can be used for up to three days after intercourse to prevent pregnancy. This method is also useful in the case of condom failure (breaking during intercourse).
Intra-uterine devices: Copper intra-uterine devices may also be used as emergency contraception. For effective prevention they must be inserted within five days of unprotected intercourse. Also, some of these devices can be places inside the uterus.
Induced abortion: In the first trimester the suction-aspiration abortion can be used to prevent unwanted childbirth. In the second trimester, dilation and evacuation has to be done to end pregnancy as long as the gestation is not more than 8 weeks.
Sterilization: Surgical sterilization can be done to prevent pregnancies. The form of tubal ligation is used in women where the fallopian tubes are cut, clamped and blocked to prevent sperm from fertilizing the egg. In men, vasectomy is done. This method is used only when the couple is sure they do not want any more children because it has a permanent effect.
Non-vaginal intercourse: Oral sex or anal sex instead of vaginal sex would reduce the chances of pregnancy. But this is not a preference of majority of couples.
Abstinence: Not indulging in sex at all is the most effective method of all to prevent pregnancy. Of course this is not a feasible method in most couples, so is not suggested by doctors.
You are right, every pregnancy is different! But for those who are just starting out its good to have a point of reference! This set of books are great and new!
Expecting 411, Baby 411 and Toddler 411 Books by Michele Hakakha, MD
Expecting 411, Baby 411 and Toddler 411 by Michele Hakakha, MD and Ari Brown, MD are wonderful books for the first time parent and for those with lots of experience! Not only are these books written by doctors they had an advisory board to help them and trust me, no detail is left out! These books are very well organized with sections and chapters and a clear question and answer format along with icons to indicate Helpful Hints, Red Flags, Old Wives Tales and Disturbing Material Ahead to name a few. The Baby 411 and Toddler 411 books have Insider Secrets and Feedback from the Real World. I highly recommend this entire set!
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