15 Words Every Baby-Making Couple Should Know

Consider the cervix the door to your reproductive system. Once ejaculated, sperm travel from the vagina into the cervix, also known as the mouth of the uterus. From there, sperm move on their way through the uterus to the fallopian tubes where at least one sperm will (ideally) meet a healthy, mature egg for fertilization.

Around the time of ovulation, your cervix secretes a thin, clear, slippery liquid -- almost the consistency of uncooked egg whites -- that helps sperm more easily navigate your reproductive tract. The presence of this fluid (you might see it on your underwear or when you wipe with toilet tissue) is a good indication that you are nearing your fertile time. Once ovulation has passed, secretions become cloudy and thick, or may disappear altogether.

During ovulation, the ends of the fallopian tubes move over the ovaries, encouraging an egg (also called an ovum) to be released. In a perfect I-want-to-get-pregnant world, the sperm meets the egg in the fallopian tube, where it is fertilized; then it makes its way into the uterus. Every woman is born with millions of eggs, but once an egg is released by the ovary, it survives for only 12 to 24 hours. Eggs that aren't fertilized are reabsorbed by the body and shed with the uterine lining during menstruation.

After an egg is fertilized by sperm, it becomes what scientists call an embryo -- essentially a clump of cells in the earliest stages of human development. Your baby will be dubbed an embryo from the time of conception until about the ninth week of pregnancy, when it's thereafter referred to as a fetus.

The fallopian tubes, located on either side of the uterus, transport an egg from the ovary to the uterus. Most eggs are fertilized in the tubes, which have small, hairlike fibers on their lining that help sweep the eggs into the uterus for implantation a trip that can take from a few hours to a few days.

Your developing baby is called a fetus (rather than an embryo) after about the ninth week of pregnancy. At this stage in development, the fetus is about the size of a strawberry; its heart, brain, hands, and feet are beginning to form. If physical malformations are to occur, they usually do so by the end of the ninth week.

FSH is a hormone secreted by the pituitary gland that helps to mature eggs so they can be successfully fertilized by sperm. (In men, FSH helps sperm production.) FSH spikes in the few days before ovulation, then falls off once an egg is released. If you're having problems conceiving, your doctor may suggest FSH testing, which can help diagnose fertility-impairing conditions like polycystic ovarian disease and even menopause.

The hormone hCg is made by the cells that form the placenta, an organ that attaches to the wall of the uterus and connects to the baby (via the umbilical cord), giving the fetus nutrients, blood and oxygen. Also known as the "pregnancy hormone," hCg can be detected in a urine test 12 to 14 days after conception and will typically double every 48 to 72 hours until about the 11th week of pregnancy, when it will taper off.

This is a hormone that prompts the ovary to release a mature egg. A surge in LH causes an egg to break through the ovary and begin its trek through the fallopian tube, where fertilization can take place. Ovulation predictor kits test for this hormone, which peaks in the 36 hours or so before ovulation; this can help you to time sex for when sperm is most likely to meet an egg.

Mittelschmerz ("middle pain" in German) is a cramp-like ache felt on one side of the lower abdomen around the time of ovulation. About 20 percent of ovulating women feel this pain, which may result from a stretching of the ovary or fluid or blood from a ruptured egg follicle irritating the lining of the stomach. The good news: Mittelschmerz, like the presence of cervical fluid, is another reliable sign that ovulation is near.

Women typically have two ovaries, one on either side of the uterus. These almond-sized, oval-shaped organs are responsible for releasing a mature egg into the fallopian tubes at ovulation so sperm can fertilize them.

Roughly 14 days before menstruation (that's day 14 of a 28-day cycle, day 16 of a 30-day cycle, etc.), a mature egg is released by an ovary and pushed into a fallopian tube, resulting in ovulation. Although sperm can live for several days, an egg can only survive for up to 24 hours after it's released, so timing sex to ovulation is critical if you want to optimize your chances of getting pregnant.

When a man ejaculates, he releases millions of his reproductive cells, also known as sperm. Sperm that have a normal shape (oval head, long tail), are excellent swimmers (i.e., more than 40 percent of the sperm in an ejaculate are moving) and are plentiful (tens of millions per ejaculate) have the best chance of fertilizing an egg.

The uterus, aka the womb, is a hollow, muscular organ located between a woman's pelvis and rectum. If an egg is fertilized, it implants itself into the uterus, which nourishes your baby until the placenta takes over. If an egg doesn't implant, the nutrient-rich lining of the uterus sheds in the form of menstrual blood.

When sperm fertilize an egg, they create a one-celled entity called a zygote -- the very beginnings of your baby. As the zygote travels through the fallopian tubes and into the uterus, it will divide, creating other clumps of cells that will eventually become an embryo, and, later, a fetus.

Copyright &copy 2011 Meredith Corporation.