Ultrasounds are not just meant for fun. They are used medically for many things during pregnancy, and they are often a necessity. During early pregnancy you a woman might be given an ultrasound for several reasons. Those reasons include previous health problems, a miscarriage or the threatening of a miscarriage, or to date your pregnancy. These types will always be done during the first trimester.

During the second trimester, normally between the 18th and 22nd week of pregnancy a woman will be given an ultrasound in order to check the baby’s lungs, heart, and brain, as well as to check for any other visible problems such as the possibility of Downs Syndrome. At this point, unless your baby is not cooperating, you can probably find out the gender of your unborn child if you want to know. Sometimes if the doctor or technician is unable to get the measurements and pictures he was looking for, they will attempt another ultrasound later in the second trimester.

If a woman chooses to have an amniocentesis, normally because of a bad test result, advanced maternal age, or previous health problems with a child, they will also have an ultrasound so that the doctor can watch as the needle enters the amniotic sac. This generally occurs around the 15th week of pregnancy.

During the third trimester an ultrasound may be offered to the parents in order to check the baby’s weight, because of lack of fetal movement, or while checking the baby’s health and stress level while doing a NST, or an amnio to check the development of the baby’s lungs.

Today pregnant women are lucky to have the option of paying out of pocket to receive an extended 3D or 4D ultrasound. These are normally not done by medical staff, but by offices as a business. They are more like souvenirs for the parents and the fee for them comes with the option to have video and pictures of their unborn baby that they can keep and show family and friends. These ultrasound sessions normally last between 30 and 90 minutes depending on what the couple pays for.

By the end of pregnancy, the baby is likely to take a position that will be favorable for the coming journey. Over 95% of all babies will be facing head down, with their chins tucked on to their chest. Some babies, particularly those of first time mothers, will literally drop into the pelvic opening. The cervix may not have dilated, and the baby is still totally within the uterus, but the head is now nestled within the pelvic opening instead of abovdrop, e it. Doctors and midwives refer to this process as engagement.

Engagement is also known as lightening, probably because it provides some relief from common pregnancy symptoms. When your baby drops, pressure on your stomach and diaphragm drops, too. You will probably have less heartburn and shortness of breath. Of course, these symptoms may merely be exchanged for new ones. You may feel increased pelvic pressure, and some women complain that it’s hard to walk because it feels like the baby’s head is between their legs. However, it’s important to remember that many women have no change in their symptoms and never even notice when the baby’s head engages. It is also possible that the baby will not drop until labor begins.

There are other signs that the time for labor may be drawing near. For example, the mucous plug, which has kept the inside of the uterus sealed off from the vagina, falls out as the cervix begins to to soften and thin in preparation for labor. The mucous plug may fall out hours or even days before labor begins. Sometimes the membranes of the amniotic sac rupture (“breaking your water”) minutes or hours before labor begins. If your membranes rupture, you should call your practitioner. Some doctors and midwives prefer that you come in for examination right away. Others will advise you to wait at home to see if labor begins spontaneously.

Many women have other physical symptoms that signal labor is approaching, including diarrhea, low backache, or abdominal cramping. It seems that impending labor may cause psychological changes as well. A few women are seized with the nesting instinct in the hours and days before labor begins. They are suddenly consumed by the urge to clean and arrange things, when just a few days before they were too exhausted to move.

Can you do anything to deliberately start your own labor? There are a lot of old (and new) wives’ tales that you can consider. Some women insist that spicy food started their labors, and others claim it was because they dosed themselves with castor oil. Then there are those who swear by sex, reasoning that even if it doesn’t work, at least they’ll have a good time. Unfortunately, it’s not likely that any of these home remedies are effective. Labor starts when the baby is ready and not one second before.

About the Author
This article was adapted from the book How Your Baby is Born, by Amy B. Tuteur, MD. Dr. Tuteur runs the website Ask Dr. Amy.com where you can ask her your questions.

The amniotic fluid is the clear, slightly yellowish fluid within the amniotic sac that surrounds the baby in the uterus. The baby grows in this amniotic sac, surrounded by the amniotic fluid, as he learns to move his limbs, open his eyes and breathe. Amniotic fluid levels generally sit at approximately 800ml through most of the pregnancy, dropping slightly in most cases to about 600ml by the time a woman reaches the 40 week mark.

The amniotic fluid has many purposes. It helps to cushion hard blows and jolts to your belly to protect the baby and it allows your baby the freedom to move while permitting symmetrical musculoskeletal development. It also maintains an even temperature so that your baby does not get too hot or too cold, even if you are extremely hot or cold.

Amniotic fluid also helps your baby develop his lungs. While in the womb your baby practices breathing by breathing in and out the water in the amniotic sac. The baby swallows and inhales the amniotic fluid and replaces the volume in the amniotic sac by urinating and exhaling the liquid.

In some cases, a woman may have too much or too little amniotic fluid. Having too much is called polyhydramnios and having too little is called oligohydramnios. In either case, a woman might be watched more closely by her physician throughout her pregnancy.