While storks and babies seem to have had a long-standing relationship for many generations, it's highly unlikely the leggy guy on the right dropped the little one on the left down his family's chimney. Click ahead to see what really led up to this little one's delivery.
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We sometimes use the phrase "You were just a twinkle in your father's eye" to refer to a time before someone was born. Well, it certainly sounds better than saying you were just one of several billion sperm in your dad's seminiferous tubules.
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Of the 300 or so million sperm that are released during ejaculation, only about 200 will survive the journey. Luckily, it only takes one of those 200 sperm to join with one egg for conception to occur.
Not all men produce this many sperm, though. If low sperm count is an issue, it can affect a couple's attempts at conception. Next, see what a fertility-challenged couple can do.
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Couples having difficulty trying to conceive aren't without options. A fertility specialist can help evaluate the situation so that a diagnosis and plan of action can be developed. Keep clicking to see what some of those solutions are.
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One option for couples facing difficulty conceiving is IVF -- in vitro fertilization. In this type of ART (assisted reproductive technology), fertilization happens outside the woman's body -- as seen here -- and then the fertilized egg is implanted into the woman's uterus where, if successful, it will result in pregnancy.
For some women, however, IVF simply won't work. Learn of a remarkable option on the next page.
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"And the woman bore her own grandchildren…" sounds like the punch line of a confused comedian. But it's what really happened with Arlette Schweitzer (on the left above) when she acted as a surrogate for her daughter.
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Home pregnancy tests like the one pictured above are the norm now but in the early 1900s, it was mostly a matter of guesswork -- and time. The reading on this test stick indicates "Pregnant." So what happens next? Keep clicking to find out.
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This illustration shows a close-up of the fetus in the womb. The smaller images show the process leading up to the fetus: the sperm swimming, the unfertilized ovum in the fallopian tube, and the ovum surrounded by sperm.
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OK so a woman's egg has been fertilized by a man's sperm. The fertilized egg, which is now called a zygote, divides one time, resulting in two cells. A few days later, those two cells become 100 cells -- the zygote is now called a blastocyst (pictured above). By the sixth day after fertilization, the blastocyst implants itself in the uterine wall, where it will continue to develop for about nine months.
Sometimes things don't go quite like this, though …
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Identical twins, like those pictured here, happen in the same way a single birth happens -- one sperm fertilizes one egg. However, shortly after fertilization, instead of the blastocyst remaining as one cell group, it splits in two.
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Conjoined twins, like these born in China, can occur when a fertilized egg doesn't completely separate.
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Is it an alien or a sea creature? Nope, it's a human embryo at six weeks gestation. You can see the yolk sac, the umbilical stalk, and along its back is the developing notochord, which will eventually become the spine. Next, see what can happen in a mere two weeks.
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By the end of the eighth week of development, the human embryo, which is now referred to as a fetus, more closely resembles a tiny human being. Here you can clearly see an eye, some internal organs, limbs, and tiny hands and feet with what look like toes and fingers.
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Here a midwife measures the fundal height of a pregnant woman during a routine check-up at Royal North Shore Hospital's Birth Centre June 7, 2006, in Sydney. Fundal height, which is measured in centimeters, is the distance from the pubic bone to the top of the uterus. The measurement is used to gauge fetal growth and gestational age -- the measurement often corresponds to a woman's pregnancy. For example, a woman who is 19 weeks pregnant could likely have a fundal height of 19 centimeters. This isn't an exact science, though, so there can be a discrepancy between the two numbers.
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From the outside, you can see your midsection expanding -- this series of images shows the development behind the scenes … a womb with a view.
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Until the 1960s, parents weren't able to share photos of their babies until well after delivery. Today, it's not uncommon for families to be passing around pictures like the one shown here -- an ultrasound image of a growing fetus (approximately 12 weeks old) inside a mother's uterus. This is a side view of the baby, showing (right to left) the head, neck, torso and legs.
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Ultrasound technology lets doctors look inside a patient's body to see everything from heart valves to a moving baby.
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The medical imaging technique of ultrasound or ultrasonography uses high frequency sound waves and their echoes to create a picture. The technique is similar to echolocation used by bats, whales and dolphins, as well as SONAR used by submarines.
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Ultrasound medical imaging technology continues to improve. In 3D ultrasound systems, several two-dimensional images are acquired by moving the probes across the body surface or rotating inserted probes. The two-dimensional scans are then combined by specialized computer software to form three-dimensional images.
With today's 4-D ultrasound technology, it's possible that this woman knows exactly what her unborn baby will look like.
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The image on this Phillips 3D ultrasound at Insight Radiology, Auckland New Zealand, is pretty clear -- you can easily see the baby's face. So it's not difficult to understand how tempting it would be to view weekly or even daily images of your impending bundle of joy -- as Tom Cruise and Katie Holmes might have planned when Cruise purchased an ultrasound machine for Holmes' pregnancy.
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Eventually, the baby grows so large that it's time to leave the womb. Although 40 weeks officially marks the end of a pregnancy, delivery can occur any time between week 37 and 42. A fetus is considered "full term" -- meaning it can function outside the womb -- at 37 weeks. If an expectant mother has not delivered by week 41 or 42, her physician will likely induce labor.
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After months of waiting, the big day has finally arrived. Labor and delivery can be both emotionally and physically intense -- but well worth it.
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Once the baby is delivered, the doctor or delivery nurse will suction amniotic fluid from the baby's nose and mouth and clamp the umbilical cord. Then the infant will be briefly wiped off with a towel and …
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A newborn baby is handed to its mother for a quick introduction. Afterward, the baby will be whisked away for a more thorough cleaning and, depending on the birth plan, he or she will be given a battery of health tests and medications, weighed and measured.
You've seen images documenting life from conception to birth. Now, test your knowledge by taking the making babies quiz