If not, the egg ends its journey at the uterus, where it either dissolves or is absorbed by the body. When pregnancy doesn't occur, the ovary eventually stops making estrogen and progesterone hormones that help maintain a pregnancy , and the thickened lining of the uterus is shed during your period. A man's body is almost constantly at work producing millions of microscopic sperm, whose sole purpose is to penetrate an egg.
While women are born with all of the eggs they'll ever need, men aren't born with ready-made sperm. They have to be produced on a regular basis, and from start to finish it takes 64 to 72 days for new sperm cells to develop. The average sperm lives only a few weeks in a man's body, and about million are released with each ejaculation. That means new sperm are always in production. Sperm begin developing in the testicles, the two glands in the scrotal sac beneath the penis.
See illustration above. The testicles hang outside a man's body because they're quite sensitive to temperature. To produce healthy sperm, testicles have to stay around 94 degrees Fahrenheit — about four degrees cooler than normal body temperature.
The sperm are stored in a part of the testicle called the epididymis before mixing with semen just prior to ejaculation. Despite the millions of sperm produced and released with each ejaculation, only one can fertilize an egg — this is the case even for identical twins. The sex of the resulting embryo depends on which type of sperm burrows into the egg first. Sperm with a Y chromosome make a boy baby, and sperm with an X chromosome make a girl. Plenty of myths about how to choose a baby's sex have been circulating for centuries.
Some are backed by a bit of scientific evidence, but a child's gender is pretty much randomly determined. Besides being pleasurable, that wonderful sensation known as an orgasm also has an important biological function. In men, having an orgasm propels sperm-rich semen into the vagina and up against the cervix, helping them reach the fallopian tubes minutes later.
This gives sperm a head start on their way to the egg. A woman's orgasm also might help conception: Some studies suggest that the wavelike contractions associated with the female orgasm pull sperm farther into the cervix but other research says there's no real evidence this is true.
Still, having an orgasm couldn't hurt — and just might help — your chances of getting pregnant. Many couples also wonder whether a particular sexual position is best for baby-making. You may have heard that certain positions are the best because they allow for deeper penetration, but there is no evidence that sex position has any effect on pregnancy rates. But do whatever you like. If the presenting part lies above the ischial spines, the station is reported as a negative number from -1 to Your baby will most often settle into a position in the pelvis before labor begins.
If your baby's spine runs in the same direction parallel as your spine, the baby is said to be in a longitudinal lie. Nearly all babies are in a longitudinal lie. If the baby is sideways at a degree angle to your spine , the baby is said to be in a transverse lie.
The normal fetal attitude is commonly called the fetal position. The head is tucked down to the chest. The arms and legs are drawn in towards the center of the chest. This position makes it easier and safer for your baby to pass through the birth canal. There are different types of cephalic presentation, which depend on the position of the baby's limbs and head fetal attitude. There are a few types of breech: A complete breech is when the buttocks present first and both the hips and knees are flexed.
A frank breech is when the hips are flexed so the legs are straight and completely drawn up toward the chest. Other breech positions occur when either the feet or knees present first. Engagement This is when the widest part of your baby's head has entered the pelvis.
Engagement tells your health care provider that your pelvis is large enough to allow the baby's head to move down descend. Descent This is when your baby's head moves down descends further through your pelvis. Most often, descent occurs during labor, either as the cervix dilates or after you begin pushing. Flexion During descent, the baby's head is flexed down so that the chin touches the chest. With the chin tucked, it is easier for the baby's head to pass through the pelvis.
Internal Rotation As your baby's head descends further, the head will most often rotate so the back of the head is just below your pubic bone. We hope that many of the things you have learned during your pregnancy and birth will also prepare you for your growth as a parent. A holistic approach to parenting and taking care of yourself while parenting offers countless benefits, including a thoughtful awareness of how you are feeling physically, emotionally, and spiritually.
Complementary therapies and practices you might have learned during pregnancy, such as massage , Reiki , and aromatherapy , can continue to offer healing comfort and relief from physical symptoms. Additionally, the methods of relaxation that you adopted during pregnancy can help relieve stress , both during your child's infancy and throughout the growth of your child.
Indeed, many parents have stated that they draw on the strength they found in childbirth during challenging times of parenting. Finally, skills you learned in advocating for yourself in the healthcare system remain important, both for yourself and for your child.
The author of one of the most famous books on childcare, Dr. Spock, starts each edition with the words, "Trust yourself. No one else will ever know your child or have his or her best interests at heart as much as you do. Listen to this affirmation. It will help you trust in your body's abilities during pregnancy and childbirth. Here are some relaxation techniques you might practice during your pregnancy that may help during childbirth. Relaxation techniques. Myla and John Kabat-Zinn. By Tracy Hogg and Melinda Blau.
By Martha Sears. By William M. More info on this topic. A holistic approach. Why go holistic? Birthing positions. What about pain? History of childbirth. How childbirth works. Factors that influence birth. Preparing for pregnancy and birth. Get birth support. Classes and birth plans. What do things look like inside? The bones and muscles of the pelvis provide support for the growing uterus and baby, and provide a passage through which your baby emerges during birth.
The uterus surrounds the baby, growing as the baby grows. The cervix is actually a part of the uterus, but made up of different tissue.
During pregnancy, the cervix is thick and closed. As you approach the time of birth, your contractions draw the cervix up into the body of the uterus, and it becomes thinner called effacement and opens called dilation. When the cervix is fully dilated about ten centimeters , contractions help the baby begin to move from the uterus into the vagina.
The vagina leads from the cervix to the outside of your body. The inside of your vagina has many folds, called rugae, which unfold as the baby passes through.
Your body's preparation for labor. Hormones work to soften the ligaments between the bones in your pelvis. Softening the ligaments gives your pelvis additional room for birth. Other hormones begin to soften your cervix. Your baby may begin moving lower in the pelvis. You may experience the passage of stringy, perhaps blood-tinged mucous. Your water may break. You may experience pre-labor contractions. Two women's stories Ginny Ginny's baby started moving lower in her pelvis about three weeks before her due date.
Lorinda Lorinda began to notice a pattern of contractions every evening about a week before her due date. Their providers' advice Ginny's doctor and Lorinda's midwife both assured these women that everything was normal, and that when things were normal, it was best to wait to go into labor and to use measures such as massage, hydrotherapy, warm packs, and Reiki to make themselves as comfortable as possible while they waited.
What can I expect emotionally? For example, if you fear a cesarean section, you might say: "I am afraid that I won't be able to give birth vaginally. For example, "I am strong and healthy, and I am well-designed to give birth. I am strong, and I can too. During your "worry time," repeat each affirmation several times and then tell yourself that worry time is over. For the remainder of the day , if you find worries creeping in, repeat the positive endings to the affirmations.
Try the guided relaxation exercise, focusing on positive mental preparation for birth. What are the stages of labor? There are three stages of labor, excluding the preparatory changes discussed above. You have contractions that work to open your cervix. You have contractions that bring your baby down into the vagina and out into the world. You assist this process by pushing.
You continue to have contractions that free the attachment of the placenta, and you push the placenta out. What influences the progression of labor? Childbirth professionals often refer to the following factors influencing labor progression as the "Four Ps" of labor: Passenger your baby Passage the pelvic bones, your cervix and vagina, and the muscles in your pelvis Power your contractions Psyche your emotions.
The dilation stage What happens in the dilation stage? What happens in the dilation stage? The dilation stage can be further subdivided into phases of early labor and active labor. What can I do during the dilation stage? Here are some additional suggestions: Try to promote a feeling of wellbeing and rest at the start of labor. A warm bath or shower, warm beverage, and a progressive relaxation exercise can help with this.
Stay well hydrated. The developing baby manages on relatively low oxygen levels while in the uterus. After birth the child is exposed to suddenly higher potentially dangerous oxygen levels.
This shift requires different ways to protect the newborn — so the baby has systems ramped up to cope with this sudden flood of oxygen. Mild jaundice, a temporary yellowing of the skin resulting from a delay in liver enzymes kicking in, may be one such protective mechanism seen in many infants. After delivery, the placental flow stops.
Understanding these processes in the first few minutes guides us in knowing when exactly to clamp the umbilical cord, and to time any breathing help needed for sick or premature newborns. The many changes a baby needs to be ready for delivery do not always have a chance to take place.
For example, if a baby is born prematurely then some or all of these adaptations may not have occurred.
Or they may have difficulty exchanging oxygen and other gases in the lungs. Despite this, all but the most premature of babies benefit from the boost of labour if possible. The changes associated with the onset of labour, particularly inflammation, trigger the biological signals that tell a baby to get ready for being born. Surprisingly, even a small deviation from normal, full-term around 40 weeks timing of labour may have effects.
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