What you’ll learn to do: explain the main stages of prenatal development
How did you come to be who you are? From beginning as a one-cell structure to your birth, your prenatal development occurred in an orderly and delicate sequence. There are three stages of prenatal development: germinal, embryonic, and fetal. Keep in mind that this is different than the three trimesters of pregnancy. Let’s take a look at what happens to the developing baby in each of these stages.
- Differentiate between development during the germinal, embryonic, and fetal periods
- Examine risks to prenatal development posed by exposure to teratogens
- Explain potential complications of pregnancy and delivery
“The body of the unborn baby is more complex than ours. The preborn baby has several extra parts to his body which he needs only so long as he lives inside his mother. He has his own space capsule, the amniotic sac. He has his own lifeline, the umbilical cord, and he has his own root system, the placenta. These all belong to the baby himself, not to his mother. They are all developed from his original cell.”
Periods of Prenatal Development
Let’s take a look at some of the changes that take place during each of the three periods of prenatal development: the germinal period, the embryonic period, and the fetal period.
The Germinal Period (Weeks 1-2)
Conception occurs when a sperm fertilizes an egg and forms a zygote, which begins as a one-cell structure. The mother and father’s DNA is passed on to the child at the moment of conception. The genetic makeup and sex of the baby are set at this point. The germinal period (about 14 days in length) lasts from conception to implantation of the zygote (fertilized egg) in the lining of the uterus.
During the first week after conception, the zygote divides and multiplies, going from a one-cell structure to two cells, then four cells, then eight cells, and so on. The process of cell division is called mitosis. After the fourth division, differentiation of the cells begins to occur as well. Differentiated cells become more specialized, forming different organs and body parts. After 5 days of mitosis, there are 100 cells, and after 9 months there are billions of cells. Mitosis is a fragile process, and fewer than one-half of all zygotes survive beyond the first two weeks (Hall, 2004).
After the zygote divides for about 7–10 days and has 150 cells, it travels down the fallopian tubes and implants itself in the lining of the uterus. It’s estimated that about 60 percent of natural conceptions fail to implant in the uterus. The rate is higher for in vitro conceptions. Once the zygote attaches to the uterus, the next stage begins.
The Embryonic Period (Weeks 3-8)
The embryonic period begins once the zygote is implanted in the uterine wall. It lasts from the third through the eighth week after conception. Upon implantation, this multi-cellular organism is called an embryo. Now blood vessels grow, forming the placenta. The placenta is a structure connected to the uterus that provides nourishment and oxygen from the mother to the developing embryo via the umbilical cord.
During this period, cells continue to differentiate. Basic structures of the embryo start to develop into areas that will become the head, chest, and abdomen. During the embryonic stage, the heart begins to beat and organs form and begin to function. At 22 days after conception, the neural tube forms along the back of the embryo, developing into the spinal cord and brain.
Growth during prenatal development occurs in two major directions: from head to tail (cephalocaudal development) and from the midline outward (proximodistal development). This means that those structures nearest the head develop before those nearest the feet and those structures nearest the torso develop before those away from the center of the body (such as hands and fingers).
The head develops in the fourth week and the precursor to the heart begins to pulse. In the early stages of the embryonic period, gills and a tail are apparent. But by the end of this stage, they disappear and the organism takes on a more human appearance. The embryo is approximately 1 inch in length and weighs about 4 grams at the end of this period. The embryo can move and respond to touch at this time.
About 20 percent of organisms fail during the embryonic period, usually due to gross chromosomal abnormalities. As in the case of the germinal period, often the mother does not yet know that she is pregnant. It is during this stage that the major structures of the body are taking form making the embryonic period the time when the organism is most vulnerable to the greatest amount of damage if exposed to harmful substances. Potential mothers are not often aware of the risks they introduce to the developing child during this time.
The Fetal Period (Weeks 9-40)
When the organism is about nine weeks old, the embryo is called a fetus. At this stage, the fetus is about the size of a kidney bean and begins to take on the recognizable form of a human being as the “tail” begins to disappear.
From 9–12 weeks, the sex organs begin to differentiate. By the 12th week, the fetus has all its body parts including external genitalia. In the following weeks, the fetus will develop hair, nails, teeth and the excretory and digestive systems will continue to develop. At the end of the 12th week, the fetus is about 3 inches long and weighs about 28 grams.
At about 16 weeks, the fetus is approximately 4.5 inches long. Fingers and toes are fully developed, and fingerprints are visible. During the 4-6th months, the eyes become more sensitive to light and hearing develops. The respiratory system continues to develop. Reflexes such as sucking, swallowing and hiccuping develop during the 5th month. Cycles of sleep and wakefulness are present at that time as well. Throughout the fetal stage, the brain continues to grow and develop, nearly doubling in size from weeks 16 to 28. The majority of the neurons in the brain have developed by 24 weeks although they are still rudimentary and the glial or nurse cells that support neurons continue to grow. At 24 weeks the fetus can feel pain (Royal College of Obstetricians and Gynecologists, 1997).
The first chance of survival outside the womb, known as the age of viability is reached at about 22 to 26 weeks (Moore & Persaud, 1998). By the time the fetus reaches the sixth month of development (24 weeks), it weighs up to 1.4 pounds. The hearing has developed, so the fetus can respond to sounds. The internal organs, such as the lungs, heart, stomach, and intestines, have formed enough that a fetus born prematurely at this point has a chance to survive outside of the mother’s womb.
Between the 7th and 9th months, the fetus is primarily preparing for birth. It is exercising its muscles, its lungs begin to expand and contract. It is developing fat layers under the skin. The fetus gains about 5 pounds and 7 inches during this last trimester of pregnancy which includes a layer of fat gained during the 8th month. This layer of fat serves as insulation and helps the baby regulate body temperature after birth.
Around 36 weeks, the fetus is almost ready for birth. It weighs about 6 pounds and is about 18.5 inches long, and by week 37 all of the fetus’s organ systems are developed enough that it could survive outside the mother’s uterus without many of the risks associated with premature birth. The fetus continues to gain weight and grow in length until approximately 40 weeks. By then, the fetus has very little room to move around and birth becomes imminent.
This video explains many of the developmental milestones and changes that happen during each month of development for the embryo and fetus.
Good prenatal care is essential. The developing child is most at risk for some of the most severe problems during the first three months of development. Unfortunately, this is a time at which most mothers are unaware that they are pregnant. It is estimated that 10% of all birth defects are caused by a prenatal exposure or teratogen. Teratogens are factors that can contribute to birth defects which include some maternal diseases, drugs, alcohol, and stress. These exposures can also include environmental and occupational exposures. Today, we know many of the factors that can jeopardize the health of the developing child. Teratogen-caused birth defects are potentially preventable.
The study of factors that contribute to birth defects is called teratology. Teratogens are usually discovered after an increased prevalence of a particular birth defect. For example, in the early 1960’s, a drug known as thalidomide was used to treat morning sickness. Exposure of the fetus during this early stage of development resulted in cases of phocomelia, a congenital malformation in which the hands and feet are attached to abbreviated arms and legs.
A Look at Some Teratogens
One of the most commonly used teratogens is alcohol. Because half of all pregnancies in the United States are unplanned, it is recommended that women of child-bearing age take great caution against drinking alcohol when not using birth control and when pregnant (Surgeon General’s Advisory on Alcohol Use During Pregnancy, 2005). Alcohol consumption, particularly during the second month of prenatal development, but at any point during pregnancy, may lead to neurocognitive and behavioral difficulties that can last a lifetime.
There is no acceptable safe limit for alcohol use during pregnancy, but binge drinking (5 or more drinks on a single occasion) or having 7 or more drinks during a single week places a child at particularly high risk. In extreme cases, alcohol consumption can lead to fetal death, but more frequently it can result in fetal alcohol spectrum disorders (FASD). This terminology is now used when looking at the effects of exposure and replaces the term fetal alcohol syndrome. It is preferred because it recognizes that symptoms occur on a spectrum and that all individuals do not have the same characteristics. Children with FASD share certain physical features such as flattened noses, small eye openings, small heads, intellectual developmental delays, and behavioral problems. Those with FASD are more at risk for lifelong problems such as criminal behavior, psychiatric problems, and unemployment (CDC, 2006).
The terms alcohol-related neurological disorder (ARND) and alcohol-related birth defects (ARBD) have replaced the term Fetal Alcohol Effects to refer to those with less extreme symptoms of FASD. ARBD include kidney, bone and heart problems.
Several medical experts debunk common myths about the safety of drinking alcohol during pregnancy.
Smoking is also considered a teratogen because nicotine travels through the placenta to the fetus. When the mother smokes, the developing baby experiences a reduction in blood oxygen levels. Tobacco use during pregnancy has been associated with low birth weight, placenta previa, birth defects, preterm delivery, fetal growth restriction, and sudden infant death syndrome. Smoking in the month before getting pregnant and throughout pregnancy increases the chances of these risks. Quitting smoking before getting pregnant is best. However, for women who are already pregnant, quitting as early as possible can still help protect against some health problems for the mother and baby.
Prescription, over-the-counter, or recreational drugs can have serious teratogenic effects. In general, if medication is required, the lowest dose possible should be used. Combination drug therapies and first trimester exposures should be avoided. Almost three percent of pregnant women use illicit drugs such as marijuana, cocaine, Ecstasy and other amphetamines, and heroin. These drugs can cause low birth-weight, withdrawal symptoms, birth defects, or learning or behavioral problems. Babies born with a heroin addiction need heroin just like an adult addict. The child will need to be gradually weaned from the heroin under medical supervision; otherwise, the child could have seizures and die.
Environmental chemicals can include an exposure to a wide array of agents including pollution, organic mercury compounds, herbicides, and industrial solvents. Some environmental pollutants of major concern include lead poisoning, which is connected with low birth weight and slowed neurological development. Children who live in older housing in which lead-based paints have been used have been known to eat peeling paint chips thus being exposed to lead. The chemicals in certain herbicides are also potentially damaging. Radiation is another environmental hazard that a pregnant woman must be aware of. If a mother is exposed to radiation, particularly during the first three months of pregnancy, the child may suffer some congenital deformities. There is also an increased risk of miscarriage and stillbirth. Mercury leads to physical deformities and intellectual disabilities (Dietrich, 1999).
Sexually Transmitted Infections
Sexually transmitted infections (STIs) can complicate pregnancy and may have serious effects on both the mother and the developing baby. Most prenatal care today includes testing for STIs, and early detection is important. STIs, such as chlamydia, gonorrhea, syphilis, trichomoniasis and bacterial vaginosis can all be treated and cured with antibiotics that are safe to take during pregnancy. STIs that are caused by viruses, like genital herpes, hepatitis B, or HIV cannot be cured. However, in some cases these infections can be treated with antiviral medications or other preventive measures can be taken to reduce the risk of passing the infection to the baby.
Maternal illnesses increase the chance that a baby will be born with a birth defect or have a chronic health problem. Some of the diseases that are known to potentially have an adverse effect on the fetus include: diabetes, cytomegalovirus, toxoplasmosis, Rubella, varicella, hypothyroidism, and Strep B. If the mother contracts Rubella during the first three months of pregnancy, damage can occur in the eyes, ears, heart, or brain of the unborn child. On a positive note, Rubella has been nearly eliminated in the industrial world due to the vaccine created in 1969. Diagnosing these diseases early and receiving appropriate medical care can help improve the outcomes. Routine prenatal care now includes screening for gestational diabetes and Strep B.
Stress represents the effects of any factor able to threaten the homeostasis of an organism; these either real or perceived threats are referred to as the “stressors” and comprise a long list of potentially adverse factors, which can be emotional or physical. Because of a link in blood supply between a mother and fetus, it has been found that stress can leave lasting effects on a developing fetus, even before a child is born. The best-studied outcomes of fetal exposure to maternal prenatal stress are preterm birth and low birth weight. Maternal prenatal stress is also considered responsible for a variety of changes of the child’s brain, and a risk factor for conditions such as behavioral problems, learning disorders, high levels of anxiety, attention deficit hyperactivity disorder, autism, and schizophrenia. Furthermore, maternal prenatal stress has been associated with a higher risk for a variety of immune and metabolic changes in the child such as asthma, allergic disorders, cardiovascular diseases, hypertension, hyperlipidemia, diabetes, and obesity.
Factors influencing prenatal risks
There are several considerations in determining the type and amount of damage that might result from exposure to a particular teratogen (Berger, 2004). These include:
- The timing of the exposure: Structures in the body are vulnerable to the most severe damage when they are forming. If a substance is introduced during a particular structure’s critical period (time of development), the damage to that structure may be greater. For example, the ears and arms reach their critical periods at about 6 weeks after conception. If a mother exposes the embryo to certain substances during this period, the arms and ears may be malformed.
- The amount of exposure: Some substances are not harmful unless the amounts reach a certain level. The critical level depends in part on the size and metabolism of the mother.
- Genetics: Genetic make-up also plays a role on the impact a particular teratogen might have on the child. This is suggested by fraternal twin studies who are exposed to the same prenatal environment, yet do not experience the same teratogenic effects. The genetic make-up of the mother can also have an effect; some mothers may be more resistant to teratogenic effects than others.
- Being male or female: Males are more likely to experience damage due to teratogens than are females. It is believed that the Y chromosome, which contains fewer genes than the X, may have an impact.
Interactive: Reducing the Risk
Did you know that pregnant women can improve outcomes for themselves and their babies through a balanced diet and adequate exercise? Click through this interactive to learn more about the importance of maternal health.
Complications of Pregnancy and Delivery
There are a number of common side effects of pregnancy. Not everyone experiences all of these nor do women experience them to the same degree. And although they are considered “minor” these problems are potentially very uncomfortable. These side effects include nausea (particularly during the first 3-4 months of pregnancy as a result of higher levels of estrogen in the system), heartburn, gas, hemorrhoids, backache, leg cramps, insomnia, constipation, shortness of breath or varicose veins (as a result of carrying a heavy load on the abdomen). What is the cure? Delivery!
The following are some serious complications of pregnancy which can pose health risks to mother and child and that often require special care.
- Gestational diabetes is when a woman without diabetes develops high blood sugar levels during pregnancy.
- Hyperemesis gravidarum is the presence of severe and persistent vomiting, causing dehydration and weight loss. It is more severe than the more common morning sickness.
- Preeclampsia is gestational hypertension. Severe preeclampsia involves blood pressure over 160/110 with additional signs. Eclampsia is seizures in a pre-eclamptic patient.
- Deep vein thrombosis is the formation of a blood clot in a deep vein, most commonly in the legs.
- A pregnant woman is more susceptible to infections. This increased risk is caused by an increased immune tolerance in pregnancy to prevent an immune reaction against the fetus.
- Peripartum cardiomyopathy is a decrease in heart function which occurs in the last month of pregnancy, or up to six months post-pregnancy.
Maternal mortality is unacceptably high. About 830 women die from pregnancy or childbirth-related complications around the world every day. It was estimated that in 2015, roughly 303,000 women died during and following pregnancy and childbirth. Almost all of these deaths occurred in low-resource settings, and most could have been prevented. The high number of maternal deaths in some areas of the world reflects inequities in access to health services and highlights the gap between rich and poor. Almost all maternal deaths (99%) occur in developing countries. More than half of these deaths occur in sub-Saharan Africa and almost one third occur in South Asia.
Almost all maternal deaths can be prevented, as evidenced by the huge disparities found between the richest and poorest countries. The lifetime risk of maternal death in high-income countries is 1 in 3,300, compared to 1 in 41 in low-income. 
Even though maternal mortality in the United States is relatively rare today because of advanced in medical care, it is still an issue that needs to be addressed. The number of reported pregnancy-related deaths in the United States steadily increased from 7.2 deaths per 100,000 live births in 1987 to 18.0 deaths per 100,000 live births in 2014. The Centers for Disease Control and Prevention define a pregnancy-related death as the death of a woman while pregnant or within 1 year of the end of a pregnancy–regardless of the outcome, duration, or site of the pregnancy–from any cause related to or aggravated by the pregnancy or its management, but not from accidental or incidental causes. The reasons for the overall increase in pregnancy-related mortality are unclear. What do you think are some reasons for this surprising increase in the United States? What can be done to change this statistic?
Watch It: Maternal Mortality in the United States
In the United States, black women are disproportionately more likely to die from complications related to pregnancy or childbirth than any other race; they are three or four times more likely than white women to die due to pregnancy-related death and are more likely to receive worse maternal care. Black women from higher income groups and with advanced education levels also have heightened risks—even tennis superstar Serena Williams had near-deadly complications during the birth of her daughter, Olympia (https://www.cnn.com/2018/01/10/health/serena-williams-birth-c-section-olympia-bn/index.html). Why is this the case in our modern world? Watch this video to learn more:
The data below shows percentages of the causes of pregnancy-related deaths in the United States during 2011–2014:
- Cardiovascular diseases, 15.2%.
- Non-cardiovascular diseases, 14.7%.
- Infection or sepsis, 12.8%.
- Hemorrhage, 11.5%.
- Cardiomyopathy, 10.3%.
- Thrombotic pulmonary embolism, 9.1%.
- Cerebrovascular accidents, 7.4%.
- Hypertensive disorders of pregnancy, 6.8%.
- Amniotic fluid embolism, 5.5%.
- Anesthesia complications, 0.3%.
The cause of death is unknown for 6.5% of all 2011–2014 pregnancy-related deaths.
Spontaneous abortion is experienced in an estimated 20-40 percent of undiagnosed pregnancies and in another 10 percent of diagnosed pregnancies. Usually, the body aborts due to chromosomal abnormalities and this typically happens before the 12th week of pregnancy. Cramping and bleeding result and normal periods return after several months. Some women are more likely to have repeated miscarriages due to chromosomal, amniotic, or hormonal problems; but miscarriage can also be a result of defective sperm (Carroll et al., 2003).
embryo: a multi-celled organism between two and eight weeks after fertilization
fetal alcohol spectrum disorders: a group of abnormalities in babies born to mothers who consume alcohol during pregnancy
fetus: an unborn human baby from nine weeks after conception until birth
mitosis: the process of cell division
placenta: a structure connected to the uterus that provides nourishment and oxygen from the mother to the developing embryo via the umbilical cord
pregnancy-related death: the death of a woman while pregnant or within 1 year of the end of a pregnancy from any cause related to or aggravated by the pregnancy
teratogen: any agent which can cause a birth defect
zygote: a one-cell structure that is created when a sperm and egg merge
- Day & Liley, The Secret World of a Baby, Random House, 1968, p. 13 ↵
- Birth Defects Research and Tracking. Centers for Disease Control and Prevention. Retrieved from https://www.cdc.gov/ncbddd/birthdefects/research.html ↵
- STDs during Pregnancy - CDC Fact Sheet. Centers for Disease Control and Prevention. Retrieved from https://www.cdc.gov/std/pregnancy/stdfact-pregnancy.htm ↵
- Maternal Illness – Birth Defect Prevention for Expecting Parents. Birth Defect Research for Children. Retrieved from https://www.birthdefects.org/healthy-baby/maternal-illness/ ↵
- Douros Konstantinos, Moustaki Maria, Tsabouri Sophia, Papadopoulou Anna, Papadopoulos Marios, Priftis Kostas N. (2017). Prenatal Maternal Stress and the Risk of Asthma in Children. Frontiers in Pediatrics. Retrieved from https://www.frontiersin.org/article/10.3389/fped.2017.00202 ↵
- Maternal mortality (↵ ). World Health Organization. Retrieved from https://www.who.int/news-room/fact-sheets/detail/maternal-mortality
- Black Women’s Maternal Health: A Multifaceted Approach to Addressing Persistent and Dire Health Disparities (April 2018). National Partnership for Women and Families. Retrieved from http://www.nationalpartnership.org/our-work/health/reports/black-womens-maternal-health.html. ↵
- Reproductive Health. Pregnancy Mortality Surveillance System. Centers for Disease Control and Prevention. Retrieved from https://www.cdc.gov/reproductivehealth/maternalinfanthealth/pregnancy-mortality-surveillance-system.htm ↵
Unajifunza nini: kueleza hatua kuu za maendeleo ya kabla ya kuzaliwa Jinsi ulivyofika kuwa wewe ni nani? Kuanzia mwanzo kama muundo wa chembe moja hadi kuzaliwa kwako, ukuzi wako wa kabla ya kuzaliwa ulitokea katika mfululizo wenye utaratibu na wa hali ya chini. Kuna hatua tatu za ukuzi wa kabla ya kuzaliwa: hatua ya kiinitete, hatua ya kiinitete, na hatua ya kiinitete. Kumbuka kwamba hii ni tofauti na miezi mitatu ya ujauzito. Hebu tuone kinachotokea kwa mtoto anayekua katika kila hatua hiyo. - Tofauti kati ya maendeleo wakati wa kipindi cha germinal, embryo, na fetal - Kuchunguza hatari kwa maendeleo ya kabla ya kuzaliwa inayosababishwa na kuambukizwa na teratogens - Kuelezea matatizo ya uwezekano wa ujauzito na kujifungua <unk>Mwili wa mtoto ambaye hajazaliwa ni tata zaidi kuliko yetu. Mtoto ambaye hajazaliwa ana sehemu kadhaa za ziada za mwili wake ambazo anahitaji tu kwa muda mrefu kama anaishi ndani ya mama yake. Pia ana chombo cha kibiolojia kinachoitwa amniotic sac. Mwili wa binadamu una umbo la kamba ya umbilical na mfumo wa mizizi ya placenta. Hizi zote ni za mtoto mwenyewe, si za mama yake. Hizi zote hutokezwa kutoka kwa chembe yake ya awali. <unk> Nyakati za Maendeleo ya Kabla ya Kuzaliwa <unk> Hebu tuchunguze baadhi ya mabadiliko yanayotokea wakati wa kila moja ya vipindi vitatu vya maendeleo ya kabla ya kuzaliwa: kipindi cha kuzaana, kipindi cha kiinitete, na kipindi cha kiinitete. Katika kipindi cha kwanza cha mimba, wakati spermatozoa hufungua yai na kuunda zygote, ambayo huanza kama muundo wa seli moja. DNA ya mama na baba hupitishwa kwa mtoto wakati wa mimba. Muundo wa urithi na jinsia ya mtoto huamuliwa wakati huo. Kipindi cha kuzaa (siku 14 hivi) huanzia wakati wa mimba hadi wakati wa kuingizwa kwa zygote (yai lililotengenezwa) ndani ya uterasi. Katika wiki ya kwanza baada ya mimba, zygote hugawanyika na kuzidisha, ikitoka kwenye chembe moja hadi chembe mbili, kisha chembe nne, kisha chembe nane, na kadhalika. Utaratibu wa kugawanyika kwa chembe huitwa mitosis. Baada ya mgawanyiko wa nne, tofauti ya chembe huanza kutokea pia. Chembe zilizotofautiana huwa maalumu zaidi, zikifanyiza viungo na sehemu tofauti-tofauti za mwili. Baada ya siku tano za mitosis, kuna chembe 100, na baada ya miezi tisa kuna mabilioni ya chembe. Mitotic ni mchakato dhaifu, na chini ya nusu ya zygotes wote kuishi zaidi ya wiki mbili za kwanza. Baada ya zygote kugawanyika kwa siku 7-10 na kuwa na chembe 150, husafiri chini ya mabomba ya uterasi na kujiingiza ndani ya uterasi. Inakadiriwa kwamba asilimia 60 ya mimba za asili hushindwa kuingizwa ndani ya tumbo la uzazi. Kiwango hicho ni cha juu zaidi kwa mimba za in vitro. Zygote inaposhikamana na tumbo la uzazi, hatua inayofuata huanza. Kipindi cha embryo (wiki 3-8): Kipindi cha embryo huanza wakati zygote inapowekwa kwenye ukuta wa tumbo la uzazi. Inaanza wiki ya tatu hadi ya nane baada ya mimba. Baada ya kuingizwa, kiumbe hicho chenye chembe nyingi huitwa kiinitete. Sasa mishipa ya damu hukua, ikifanyiza mkojo. Mto ni sehemu ya tumbo la uzazi ambayo hutoa chakula na oksijeni kutoka kwa mama hadi kwa kiinitete kupitia kamba ya tumbo. Katika kipindi hicho, chembe huendelea kutofautika. Miundo ya msingi ya kiinitete huanza kuendeleza katika maeneo ambayo yatakuwa kichwa, kifua, na tumbo. Wakati wa hatua ya kiinitete, moyo huanza kupiga na viungo hufanyizwa na kuanza kufanya kazi. Siku 22 baada ya mimba, bomba la neva hufanyizwa kwenye sehemu ya nyuma ya kiinitete, na kugeuka kuwa uti wa mgongo na ubongo. Ukuaji wakati wa maendeleo ya kabla ya kuzaliwa hutokea katika mwelekeo kuu mbili: kutoka kichwa hadi mkia (kuendeleza cephalocaudal) na kutoka katikati ya nje (kuendeleza proximodistal). Hii inamaanisha kwamba miundo iliyo karibu na kichwa huendelea kabla ya ile iliyo karibu na miguu na miundo iliyo karibu na mwili huendelea kabla ya ile iliyo mbali na katikati ya mwili (kama vile mikono na vidole). Kichwa hufanyizwa katika juma la nne na kiambishi cha moyo huanza kupiga. Katika hatua za mapema za kipindi cha kiinitete, matumbo na mkia huonekana. Lakini mwishoni mwa hatua hii, wao hutoweka na kiumbe huonekana kuwa na umbo la kibinadamu zaidi. Kiinitete kina urefu wa karibu inchi 1 na uzito wa gramu 4 mwishoni mwa kipindi hiki. Wakati huo kiinitete kinaweza kuhama na kujibu kuguswa. Karibu asilimia 20 ya viumbe hufa wakati wa kipindi cha kiinitete, kwa kawaida kwa sababu ya kasoro kubwa za kromosomu. Kama ilivyo katika kipindi cha kuzaa, mara nyingi mama hajui bado kwamba ana mimba. Katika hatua hii, miundo mikubwa ya mwili huanza kuunda, na kipindi cha kiinitete ni wakati ambapo viumbe ni hatari zaidi kwa uharibifu mkubwa ikiwa vimefunikwa na vitu vyenye madhara. Mara nyingi mama wanaotarajia kuwa mama hawajui hatari wanazotoa kwa mtoto anayekua wakati huo. "Mwaka wa mimba (mwaka wa 9 hadi 40) ni wakati ambapo mtoto ana umri wa wiki tisa au zaidi, na wakati huo huo mtoto anaitwa ""mzazi.""" Katika hatua hii, kijusi ni kuhusu ukubwa wa maharagwe figo na huanza kuchukua fomu inayojulikana ya binadamu kama <unk>mwiba<unk> huanza kutoweka. Katika wiki 9-12 ya mimba, viungo vya uzazi huanza kutofautisha. Katika wiki ya 12, mtoto ana sehemu zote za mwili, ikiwa ni pamoja na viungo vya uzazi vya nje. Katika wiki zifuatazo, mtoto atazalisha nywele, misumari, meno na mfumo wa kutolea nje na wa kumeng'enya chakula utaendelea kuendeleza. Katika wiki ya 12, kijusi ni karibu sentimita 3 kwa urefu na uzito wa gramu 28. Katika wiki ya 16, kijusi ni karibu inchi 4.5 kwa urefu. Vidole vya mikono na miguu vimeendelea kikamili, na alama za vidole zinaonekana. Katika miezi ya nne na sita, macho huwa nyeti zaidi kwa mwanga na kusikia huendelea. Mfumo wa kupumua unaendelea kukua. Reflexes kama vile kunyonya, kumeza na hiccuping huanza katika mwezi wa tano. Mzunguko wa usingizi na wa kuamka unapatikana wakati huo pia. Wakati wa mimba, ubongo huendelea kukua na kupanuka, na karibu mara mbili kwa ukubwa kutoka wiki 16 hadi 28. Kwa kawaida, neuroni huanza kukua katika wiki 24 na seli za glial au za muuguzi huendelea kukua. Katika wiki ya 24 ya mimba, mtoto anaweza kuhisi maumivu (Royal College of Obstetricians and Gynecologists, 1997). Uwezekano wa kwanza wa kuishi nje ya tumbo la uzazi, unaojulikana kama umri wa uwezo wa kuishi, hufikia karibu wiki 22 hadi 26 (Moore & Persaud, 1998). Wakati fetusi inafikia miezi sita ya ukuzi (miaka 24), inazidi uzito wa kilo 1.4. Kwa kuwa fetusi ina uwezo wa kusikia, inaweza kujibu sauti. Viungo vya ndani, kama vile mapafu, moyo, tumbo, na matumbo, vimekuwa vimefanyizwa vya kutosha hivi kwamba mtoto aliyezaliwa kabla ya wakati ana nafasi ya kuishi nje ya tumbo la mama. Katika miezi ya 7 hadi 9, mtoto wa kiume anaendelea kuandaa kwa ajili ya kuzaliwa. Mwili hufanya mazoezi ya misuli na mapafu huanza kupanuka na kukata. Inaunda tabaka za mafuta chini ya ngozi. Mimba huongeza uzito wa kilo tano na inchi saba katika miezi mitatu ya mwisho ya ujauzito, na inaongeza mafuta katika miezi ya nane. Tabaka hilo la mafuta hutumika kama kinga na husaidia mtoto kudhibiti halijoto ya mwili baada ya kuzaliwa. Katika wiki ya 36 ya mimba, mtoto yuko tayari kuzaliwa. Kwa kuwa mtoto huyo ana uzito wa kilo 6 na urefu wa inchi 18.5, katika wiki ya 37 ya mimba, mfumo wote wa viungo vya mtoto huyo umesitawi vya kutosha ili aweze kuishi nje ya tumbo la mama bila hatari nyingi zinazohusiana na kuzaliwa kabla ya wakati. Mimba huendelea kuongezeka uzito na urefu hadi wiki 40. Kufikia wakati huo, kijusi hicho kina nafasi kidogo sana ya kuzunguka-zunguka na kuzaliwa kunakuwa karibu. Video hii inaelezea hatua nyingi za maendeleo na mabadiliko yanayotokea wakati wa kila mwezi wa maendeleo ya kiinitete na kijusi. Utunzaji mzuri kabla ya kujifungua ni muhimu. Mtoto anayeendelea kukua ana hatari kubwa zaidi ya kupata matatizo makali zaidi katika miezi mitatu ya kwanza ya ukuzi. Kwa kusikitisha, wakati huo ni wakati ambao akina mama wengi hawajui kwamba wako mjamzito. Inakadiriwa kuwa asilimia 10 ya kasoro zote za kuzaliwa hutokana na athari za dawa za kulevya au teratogens. Teratogens ni sababu ambazo zinaweza kuchangia kasoro za kuzaliwa ambazo ni pamoja na magonjwa fulani ya mama, dawa za kulevya, pombe, na mkazo. Madhara haya yanaweza pia kujumuisha athari za mazingira na kazi. Leo, tunajua mambo mengi yanayoweza kuhatarisha afya ya mtoto anayekua. Kasoro za kuzaliwa zinazosababishwa na teratogeni zaweza kuepukwa. Utafiti wa mambo yanayochangia kasoro za kuzaliwa huitwa teratolojia. Kwa kawaida teratogeni hugunduliwa baada ya kuongezeka kwa kasoro fulani ya kuzaliwa. Kwa mfano, mwanzoni mwa miaka ya 1960, dawa iitwayo thalidomide ilitumiwa kutibu ugonjwa wa asubuhi. Ugonjwa huo unaitwa phocomelia, na ni ugonjwa wa kuzaliwa ambao huathiri mikono na miguu. Mmoja wa teratogens zinazotumiwa kwa kawaida ni pombe. "Kwa sababu nusu ya mimba zote nchini Marekani hazikusudiwa, inashauriwa kwamba wanawake wa umri wa kuzaa watoto wawe makini sana dhidi ya kunywa pombe wakati hawajatumia njia za kuzuia uzazi na wakati wa ujauzito (Surgeon General's Advisory on Alcohol Use During Pregnancy, 2005).""" Kunywa pombe, hasa wakati wa mwezi wa pili wa mimba, lakini wakati wowote wakati wa ujauzito, inaweza kusababisha matatizo ya neurocognitive na tabia ambayo inaweza kudumu maisha yote. Hakuna kiwango cha usalama cha kunywa pombe wakati wa ujauzito, lakini kunywa pombe kupita kiasi (kinywaji 5 au zaidi kwa mara moja) au kunywa pombe 7 au zaidi kwa wiki moja huweka mtoto katika hatari kubwa. Katika hali mbaya, kunywa pombe kunaweza kusababisha kifo cha mtoto mchanga, lakini mara nyingi zaidi kunaweza kusababisha matatizo ya utoaji pombe. Neno hilo sasa linatumiwa wakati wa kuchunguza athari za kuambukizwa na badala ya neno ugonjwa wa kileo cha kijusi. Ni bora kwa sababu inatambua kwamba dalili hutokea kwenye wigo na kwamba watu wote hawana sifa sawa. Watoto wenye FASD wana sifa fulani za mwili kama vile pua zilizopigwa, macho madogo, vichwa vidogo, kuchelewa kwa maendeleo ya akili, na matatizo ya tabia. Watu wenye FASD wana hatari kubwa ya matatizo ya maisha kama vile tabia ya uhalifu, matatizo ya kisaikolojia, na ukosefu wa ajira (CDC, 2006). "Neno ""Alcohol-Related Neurological Disorder"" (ARND) na ""Alcohol-Related Birth Defects"" (ARBD) ni maneno ya kawaida ya utambuzi wa ugonjwa wa akili unaohusiana na kileo." ARBD ni pamoja na matatizo ya figo, mifupa na moyo. Wataalamu kadhaa wa kitiba wanashutumu hadithi za kawaida kuhusu usalama wa kunywa kileo wakati wa ujauzito. Uvutaji sigareti pia huonwa kuwa chanzo cha ugonjwa huo kwa sababu nikotini husafiri kupitia tumbo la uzazi hadi kwa kijusi. Mama anapovuta sigareti, mtoto anayekua hupata kiwango cha oksijeni katika damu. Matumizi ya tumbaku wakati wa ujauzito yamehusianishwa na uzito wa chini wa kuzaliwa, placenta previa, kasoro za kuzaliwa, kuzaliwa kabla ya wakati, kizuizi cha ukuaji wa kijusi, na ugonjwa wa kifo cha ghafula cha mtoto mchanga. Kuvuta sigareti mwezi mmoja kabla ya kupata mimba na wakati wote wa ujauzito huongeza uwezekano wa hatari hizi. Kuacha kuvuta sigareti kabla ya kupata mimba ni jambo bora zaidi. Hata hivyo, kwa wanawake ambao tayari ni wajawazito, kuacha mapema iwezekanavyo bado inaweza kusaidia kulinda dhidi ya matatizo fulani ya afya kwa mama na mtoto. Dawa za kulevya, zinazouzwa bila dawa, au zinazotumiwa kwa ajili ya tafrija zaweza kuwa na madhara makubwa ya kuharibu mwili. Kwa ujumla, ikiwa dawa inahitajika, kipimo cha chini zaidi kinachowezekana kinapaswa kutumiwa. Matibabu ya dawa ya mchanganyiko na mfiduo wa trimester ya kwanza inapaswa kuepukwa. Karibu asilimia tatu ya wanawake wajawazito hutumia dawa za kulevya haramu kama vile bangi, kokeini, ecstasy na dawa nyingine za kulevya, na heroini. Dawa hizo zaweza kusababisha uzani mdogo wa kuzaliwa, dalili za kuacha, kasoro za kuzaliwa, au matatizo ya kujifunza au ya tabia. Watoto wanaozaliwa wakiwa na uraibu wa heroini huhitaji heroini kama vile mraibu mzima anavyohitaji. Mtoto atahitaji kuondolewa heroini hatua kwa hatua chini ya uangalizi wa daktari; la sivyo, mtoto anaweza kupatwa na mshtuko wa akili na kufa. Kemikali za mazingira zinaweza kujumuisha mfiduo wa aina mbalimbali za mawakala ikiwa ni pamoja na uchafuzi, misombo ya kikaboni ya zebaki, dawa za kuua magugu, na vimumunyisho vya viwandani. Baadhi ya uchafuzi wa mazingira wa wasiwasi mkubwa ni pamoja na sumu ya risasi, ambayo ni kushikamana na uzito wa chini wa kuzaliwa na kupunguza maendeleo ya neva. Watoto wanaoishi katika nyumba za zamani ambazo rangi za risasi zimetumiwa wamekuwa wakila vipande vya rangi vinavyopungua na hivyo kufunuliwa risasi. Kemikali zilizo katika dawa fulani za kuua magugu pia zinaweza kuharibu. Mionzi ni hatari nyingine ya mazingira ambayo mwanamke mjamzito anapaswa kuwa na ufahamu. Ikiwa mama anaathiriwa na mionzi, hasa katika miezi mitatu ya kwanza ya ujauzito, mtoto anaweza kuwa na kasoro fulani za kuzaliwa. Pia kuna hatari kubwa ya kuharibika kwa mimba na kuzaliwa akiwa amekufa. Mercury husababisha kasoro za kimwili na ulemavu wa akili (Dietrich, 1999). Maambukizo ya zinaa (STI) yanaweza kusababisha matatizo ya mimba na kuathiri sana mama na mtoto. Matibabu mengi ya kabla ya kujifungua leo yanatia ndani kupimwa virusi vya zinaa, na kugundua mapema ni jambo muhimu. Vifo kama vile chlamydia, gonorrhea, syphilis, trichomoniasis na bakteria vaginosis vinaweza kutibiwa na kuponywa kwa kutumia dawa za kuua viini ambazo ni salama kuchukua wakati wa ujauzito. Ugonjwa wa zinaa unaosababishwa na virusi kama vile herpes ya uzazi, hepatitis B, au HIV hauwezi kutibiwa. Hata hivyo, katika baadhi ya kesi maambukizi haya yanaweza kutibiwa na dawa za antiviral au hatua nyingine za kuzuia zinaweza kuchukuliwa ili kupunguza hatari ya kupitisha maambukizo kwa mtoto. Ugonjwa wa mama huongeza uwezekano wa mtoto kuzaliwa na kasoro ya kuzaliwa au kuwa na tatizo la afya la kudumu. Baadhi ya magonjwa ambayo yanajulikana kuwa na athari mbaya kwa kijusi ni pamoja na: kisukari, cytomegalovirus, toxoplasmosis, Rubella, varicella, hypothyroidism, na Strep B. Ikiwa mama anapata ugonjwa wa Rubella katika miezi mitatu ya kwanza ya ujauzito, anaweza kuharibu macho, masikio, moyo, au ubongo wa mtoto ambaye hajazaliwa. Kwa upande mwingine, ugonjwa wa Rubella umepungua sana katika nchi za Ulaya na Ulaya kwa sababu ya chanjo ya ugonjwa huo. Kuchunguza magonjwa hayo mapema na kupokea matibabu yanayofaa kunaweza kusaidia kuboresha matokeo. Matibabu ya kawaida ya kabla ya kujifungua sasa yanatia ndani uchunguzi wa kisukari cha mimba na Strep B. Mkazo ni athari za sababu yoyote inayoweza kutishia homeostasis ya kiumbe; vitisho hivi halisi au vinavyoonekana vinaitwa "vitu vya kushinikiza" na vina orodha ndefu ya sababu mbaya, ambazo zinaweza kuwa za kihemko au za kimwili. Kwa sababu ya uhusiano wa damu kati ya mama na mtoto, imegunduliwa kwamba mkazo waweza kuwa na athari za kudumu kwenye mtoto anayekua, hata kabla ya kuzaliwa. Matokeo yaliyochunguzwa vizuri zaidi ya mfiduo wa kijusi kwa mkazo wa kabla ya kuzaliwa kwa mama ni kuzaliwa kabla ya wakati na uzito wa chini wa kuzaliwa. Mkazo wa kabla ya kuzaliwa pia huchukuliwa kuwa na jukumu la mabadiliko mbalimbali ya ubongo wa mtoto, na sababu ya hatari ya hali kama vile matatizo ya tabia, matatizo ya kujifunza, viwango vya juu vya wasiwasi, shida ya uangalifu, ugonjwa wa hyperactivity, autism, na schizophrenia. Kwa kuongezea, mkazo wa kabla ya kuzaliwa kwa mama umehusishwa na hatari kubwa ya mabadiliko mbalimbali ya kinga na kimetaboliki katika mtoto kama vile pumu, matatizo ya mzio, magonjwa ya moyo, shinikizo la damu, hyperlipidemia, kisukari, na unene. Kuna mambo kadhaa ya kuzingatia katika kuamua aina na kiasi cha uharibifu ambao unaweza kutokea kutokana na mfiduo wa teratogen fulani (Berger, 2004). Hizi ni pamoja na: - Wakati wa mfiduo: Miundo katika mwili ni dhaifu kwa uharibifu mkubwa zaidi wakati wao ni kuunda. Kama dutu ni kuletwa wakati maalum muundo wa kipindi muhimu (wakati wa maendeleo), uharibifu kwa muundo huo inaweza kuwa kubwa. Kwa mfano, masikio na mikono hufikia kipindi chao muhimu karibu wiki sita baada ya mimba. Ikiwa mama humwekea kiinitete katika hali ya kuathiriwa na vitu fulani wakati huo, huenda mikono na masikio yakawa na kasoro. - Kiasi cha mfiduo: Baadhi ya vitu si hatari isipokuwa kiasi hufikia kiwango fulani. Kiwango hicho muhimu hutegemea kwa sehemu ukubwa na kimetaboliki ya mama. - Urithi: Urithi wa urithi pia huathiri jinsi kiumbe fulani anayeweza kusababisha ugonjwa wa kuambukiza mtoto anavyoweza kumsababisha mtoto. Utafiti wa watoto wawili wa mapacha unaonyesha kwamba wanaishi katika mazingira sawa kabla ya kuzaliwa lakini hawana athari sawa za teratogenic. Uundaji wa urithi wa mama pia waweza kuwa na athari; baadhi ya mama wanaweza kuwa na sugu zaidi kwa athari za teratogenic kuliko wengine. - Kuwa wa kiume au wa kike: Wanaume wana uwezekano mkubwa zaidi wa kupata uharibifu kutokana na teratogens kuliko wanawake. Inaaminika kwamba kromosomu ya Y, ambayo ina chembe za urithi chache kuliko X, yaweza kuwa na uvutano. "Kama unavyojua, wanawake wajawazito wanaweza kuboresha matokeo kwa ajili yao wenyewe na watoto wao kupitia chakula cha usawa na mazoezi ya kutosha. """ Fanya hivyo kwa kutumia hii interactively na kujifunza zaidi kuhusu jinsi ya kuimarisha afya ya watoto. Matatizo ya ujauzito na kuzaa Kuna athari kadhaa za kawaida za ujauzito. Si kila mtu anayepitia mambo hayo yote wala wanawake hawajapatwi nayo kwa kiwango kilekile. Na ingawa wao ni kuchukuliwa <unk>madogo<unk> matatizo haya ni uwezekano wa kutokuwa na furaha sana. Madhara haya ni pamoja na kichefuchefu (hasa katika miezi ya kwanza ya ujauzito, kutokana na viwango vya juu vya estrogen katika mfumo), maumivu ya moyo, gesi, hemorrhoids, mgongo, mgongo mgongo, insomnia, constipation, upungufu wa pumzi au mishipa ya varicose (kwa sababu ya kubeba mzigo mzito kwenye tumbo). Ni nini tiba? Utoaji! Madhara ya ujauzito yanaweza kuwa hatari kwa afya ya mama na mtoto na mara nyingi yanahitaji uangalifu maalum. - Ugonjwa wa kisukari wa mimba ni wakati mwanamke asiye na ugonjwa wa kisukari anapata viwango vya juu vya sukari ya damu wakati wa ujauzito. - Hyperemesis gravidarum ni uwepo wa kutapika kali na kwa kuendelea, kusababisha dehydration na kupoteza uzito. Ni mbaya zaidi kuliko ugonjwa wa asubuhi unaopatikana kwa kawaida. - Preeclampsia ni shinikizo la damu la ujauzito. Preeclampsia kali ni hali ya shinikizo la damu juu ya 160-110 na dalili za ziada. Eclampsia ni mshtuko wa moyo kwa mgonjwa aliye na ugonjwa wa kabla ya kuambukizwa. - Deep vein thrombosis ni malezi ya damu clot katika vena ya kina, kawaida katika miguu. - Mwanamke mjamzito huathiriwa zaidi na maambukizo. Hatari hii iliyoongezeka husababishwa na kuongezeka kwa uvumilivu wa kinga wakati wa ujauzito ili kuzuia athari ya kinga dhidi ya kijusi. Cardiomyopathy ya Peripartum ni kupungua kwa kazi ya moyo ambayo hutokea katika mwezi wa mwisho wa ujauzito, au hadi miezi sita baada ya ujauzito. Kiwango cha vifo vya akina mama ni cha juu sana. Kila siku, wanawake 830 duniani kote hufa kutokana na matatizo yanayohusiana na ujauzito au kuzaa. Kwa mujibu wa takwimu za mwaka 2015, wanawake 303,000 walifariki katika kipindi cha ujauzito na baada ya kujifungua. Karibu vifo vyote hivyo vilitokea katika mazingira yenye rasilimali chache, na vingi vingeweza kuzuiwa. Idadi kubwa ya vifo vya akina mama katika maeneo fulani ya dunia huonyesha ukosefu wa usawa katika upatikanaji wa huduma za afya na inasisitiza pengo kati ya matajiri na maskini. Karibu vifo vyote vya mama (99%) hutokea katika nchi zinazoendelea. Zaidi ya nusu ya vifo hivyo hutokea katika Afrika kusini mwa Jangwa la Sahara na karibu thuluthi moja hutokea katika Asia Kusini. Karibu vifo vyote vya akina mama vinaweza kuzuiwa, kama inavyoonyeshwa na tofauti kubwa zilizopatikana kati ya nchi tajiri na maskini. Uwezekano wa kifo cha mama katika nchi zenye mapato ya juu ni 1 kwa 3,300, ikilinganishwa na 1 kwa 41 katika nchi zenye mapato ya chini. Ingawa vifo vya akina mama nchini Marekani ni nadra sana leo kwa sababu ya maendeleo ya matibabu, bado ni suala ambalo linahitaji kushughulikiwa. Idadi ya vifo vinavyohusishwa na mimba nchini Marekani imepanda kwa kasi kutoka 7.2% kwa kila 100,000 ya kuzaliwa hai mwaka 1987 hadi 18.0% kwa kila 100,000 ya kuzaliwa hai mwaka 2014. "Kati ya ""kifo kinachohusiana na ujauzito"" ni kifo cha mwanamke wakati wa ujauzito au ndani ya mwaka mmoja baada ya kumaliza ujauzito, bila kujali matokeo, muda, au eneo la ujauzito, kutokana na sababu yoyote inayohusiana na au kuongezeka na ujauzito au usimamizi wake, lakini sio kutokana na sababu za ajali au za bahati mbaya." Sababu za ongezeko la jumla la vifo vinavyohusiana na ujauzito hazijulikani wazi. Unafikiri ni nini kinachosababisha ongezeko hilo la kushangaza nchini Marekani? Ni nini kinachoweza kufanywa ili kubadilisha takwimu hii? "Kama ilivyoelezwa katika ripoti ya ""Mothers' Mortality in the United States,"" wanawake weusi wana uwezekano mkubwa wa kufa kutokana na matatizo yanayohusiana na ujauzito au kuzaa kuliko jamii nyingine yoyote, na wana uwezekano mkubwa mara tatu au nne zaidi ya wanawake weupe wa kufa kutokana na vifo vinavyohusiana na ujauzito na wana uwezekano mkubwa wa kupata huduma mbaya zaidi ya uzazi." Wanawake weusi kutoka vikundi vya mapato ya juu na wenye viwango vya elimu ya juu pia wana hatari kubwa - hata nyota wa tenisi Serena Williams alikuwa na matatizo ya karibu ya kifo wakati wa kuzaliwa kwa binti yake, Olympia (https: www.cnn.com 2018-01-10). Kwa nini hali iko hivyo katika ulimwengu wetu wa kisasa? Kwa mujibu wa ripoti ya utafiti wa utafiti, asilimia ya vifo vinavyohusiana na mimba nchini Marekani katika mwaka 2011-2014 ni kutokana na magonjwa ya moyo na mishipa ya damu. - Ugonjwa wa moyo na mishipa ya damu (non-cardiovascular diseases) - 14.7%. Ugonjwa wa kuambukiza au sepsis - 12.8% - Ugonjwa wa damu, 11.5%. Ugonjwa wa moyo (cardiomyopathy) ni ugonjwa wa moyo unaoathiri asilimia 10.3 ya watu. - Thrombotic pulmonary embolism, 9.1%. - Ugonjwa wa mshipa wa damu, 7.4%. - Matatizo ya shinikizo la damu wakati wa ujauzito, 6.8%. - Embolism ya maji ya amniotic, 5.5%. - Matatizo ya anesthesia, 0.3%. Sababu ya kifo haijulikani kwa 6.5% ya vifo vyote vya ujauzito vya 2011-2014 Utoaji mimba wa kawaida hutokea katika asilimia 20 hadi 40 ya mimba zisizogunduliwa na katika asilimia 10 ya mimba zilizogunduliwa. Kwa kawaida, mimba hutoweka kwa sababu ya kasoro za kromosomu, na hii hutokea kabla ya wiki ya 12 ya ujauzito. Matokeo ya maumivu na kutokwa na damu na vipindi vya kawaida hurudi baada ya miezi kadhaa. Wanawake wengi wanakabiliwa na matatizo ya utoaji mimba kwa sababu ya matatizo ya kromosomu, amniotic, au hormonal, lakini pia inaweza kuwa na matokeo ya utoaji mimba kwa sababu ya spermatozoa (Carroll et al., 2003). Matatizo ya utoaji wa pombe: Mwili wa mtoto unaoishi katika utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe, na ambayo huathiri utoaji wa pombe. - L. L. R. Paley, The Secret of a Baby, 1968 Vituo vya Kudhibiti na Kuzuia Magonjwa. Imetolewa kutoka https: www.cdc.gov/ncbddd/birthdefects.html <unk> - STDs wakati wa ujauzito - CDC Fact Sheet. Vituo vya Kudhibiti na Kuzuia Magonjwa. "Kutoka kwa ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Ugonjwa wa Mama"" na ""Mafunzo ya Mama"" na ""Mafunzo wa Mama.""" Utafiti wa Kasoro za Kuzaliwa kwa Watoto. "Kutoka kwa ""Mwanamke wa Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi cha Kizazi.""" Mkazo wa Mama kabla ya Kuzaliwa na Hatari ya Pumu Katika Watoto. Frontiers katika Pediatrics. "Kama ilivyoelezwa katika makala ya ""Mwanzo wa Ugonjwa wa Matibabu"" ya www.fertility.org, ""Mwanzo wa Ugonjwa wa Matibabu"" ni ""Mwanzo wa Ugonjwa wa Matibabu"" na ""Mwanzo wa Ugonjwa wa Matibabu"" ni ""Mwanzo wa Ugonjwa wa Matibabu.""" Shirika la Afya Ulimwenguni. "Kama ilivyoelezwa katika makala ya ""Mwanamke wa Black: Njia ya Multifaceted ya Kukabiliana na Tofauti za Afya za Kudumu na Zito"" (April 2018)." Ushirikiano wa Kitaifa kwa Wanawake na Familia. "Kama ilivyoelezwa katika ukurasa wa ""Mwanamke wa Marekani"" (http: www.mwanamke-uingereza.com) na ""Mwanamke wa Marekani"" (http: www.mwanamke-uingereza) na ""Mwanamke wa Marekani"" (http: www.mwanamke-uingereza)."  - Afya ya Uzazi. Mfumo wa Ufuatiliaji wa Vifo vya Mimba. Vituo vya Kudhibiti na Kuzuia Magonjwa. Imetolewa kutoka https: www.cdc.gov/reproductivehealth/maternalinfanthealth/pregnancy-mortality-surveillance-system.htm 