Conception The process of becoming pregnant involving fertilization or implantation or both
The Reproductive Process • Human reproduction is a function of the male and female reproductive systems.
The Female Reproductive System • Females are born with thousands of reproductive cells, called ova, or eggs. Ova are stored in the woman's ovaries. • Ovaries- Two oval shaped reproductive organs that hold the ova. • Uterus- or womb, the organ in which the unborn baby develops. • Ovulation-A woman's monthly cycle is measured from the first day of her menstrual period until the first day of her next period. Average length of a cycle is 28-32days. • Fallopian tubes- tubes through which the eggs (ova) pass on their way from the ovary to the uterus.
Keys Facts About Ovulation • An egg lives 12-24 hours after leaving the ovary • Normally only one egg is released each time of ovulation • Ovulation can be affected by stress, illness or disruption of normal routines • Implantation of a fertilized egg normally takes place 6-12 days after ovulation • Each woman is born with millions of immature eggs that are awaiting ovulation to begin • A menstrual period can occur even if ovulation has not occurred • Some women can feel a bit of pain or aching near the ovaries during ovulation called mittelschmerz, which means "middle pain" in German • If an egg is not fertilized, it disintegrates and is absorbed into the uterine lining
The Male Reproductive System • Sperm- the male reproductive cells. 400-500 million are released at one time. Often called semen. • Testes- sperm is produced and stored in two testes.
Conception Process • Conception occurs when male and female reproductive cells unite after sexual intercourse. During intercourse sperm are deposited near the lower end of the uterus. The sperm quickly swim toward the fallopian tubes. If a ova is present the sperm will swarm and try to break through the surface. Only one will be successful and the other sperm will eventually die. • Deposited sperm can live up to four to five days inside the female body. An ovum typically can live for 24-48 hours in the fallopian tubes. • http://www.youtube.com/watch?v=Gc1L61FpAnY&feature=related
Myths About Becoming Pregnant • Can pregnancy occur before the a girls first menstrual period? • Yes. • Can pregnancy occur the first time? • Yes • Can pregnancy occur during a menstrual period? • Yes • Can pregnancy occur even if intercourse is incomplete? • Yes.
Fertility Problems • Infertile- unable to conceive a child after trying for at least 12 months. • About 8-12% of couples world wide are infertile. • About 40 % of all fertility problems among couples is due to male infertility. • The three most common cause of male infertility are • Low production of sperm • Impaired delivery of sperm • Low production of the male sex hormone
Fertility • Infertility of women is usually due to damaged fallopian tubes, endometriosis, hormonal imbalance which delays the ovulation cycle.
Treatment for Infertility • Physicians can test for infertility causes and offer treatments. • Depending on the cause artificial insemination may be a solution. • Another possibility is in vitro fertilization. This is where an egg is surgically removed and implanted with male sperm then put back in the mothers uterus.
Multiple Births • Fraternal Twins- usually occur when two fertilized eggs are implanted in the uterine wall at the same time. When two eggs are independently fertilized by two different sperm cells, fraternal twins result. The two eggs, or ova, form two zygotes. Often different gender, different looks, and personality. They are from different eggs and sperm. Hereditary…? • Identical Twins- occur when a single egg is fertilized to form one zygote which then divides into two separate embryos. They are the same sex and their traits and physical appearances are very similar but not exactly the same; although they have nearly identical DNA,environmental conditions both inside the womb and throughout their lives influence the switching on and off of various genes. Division of the zygote into two embryos is not considered to be a hereditary trait, but rather an anomaly that occurs in birthing at a rate of about three in every 1000 deliveries worldwide, regardless of race. The two embryos develop into fetuses sharing the same womb.
Problems With Multiple Births • Vanishing Twin- 1 in 8 births start out as multiple but usually one dies off very early on and is often undetected. • Parasitic Twin- Sometimes one twin can be compromising the other twins health • Miscarried Twin- When one twin dies before birth • Low-Birth Weight- Often born early, weigh a lot less and are typically smaller their whole lives than single born babies.
http://health.discovery.com/beyond/ • http://video.google.com/videosearch?hl=en&source=hp&q=conception&um=1&ie=UTF-8&sa=N&tab=wv#