Women's Healthcare Topics
James Brann, MD. Ob/Gyn

16 Weeks Pregnant

Pregnant Belly Changes

Congratulations, you are showing! By 16 weeks pregnant, it may be hard to hide your growing "bump" from the world. As your pregnancy continues, you will be amazed at how fast your belly grows. It won't be long before you need to start shopping for maternity wear.

If you want to keep your pregnancy a secret for a little bit longer, you may want to consider wearing baggier clothes. From now on your growing belly will be more pronounced in tight-fitting clothes.

If you haven't already, you will soon start to feel the tiny fluttering of your baby swimming in your uterus. Although "quickening" (feeling your baby move) is more common in pregnancy week 17 and onward, some pregnant women do experience these movements earlier. At 16 weeks pregnant, these early movements might feel like gas bubbles or little flutters. In the next few weeks, they will grow stronger and you will be able to feel them more often.

Most women are feeling pretty good at now. The queasiness, fatigue, and frequent urination that plagued you earlier in pregnancy are completely gone for many women. (For some mamas-to-be, they feel nauseous and exhausted throughout all 40 weeks. Remember that every pregnancy is different.)

The pregnancy "glow" is probably noticeable now. Friends and family may start commenting on your glowing, rosy skin. Even if your bump isn't too noticeable, people might tell you that you just look pregnant. This proverbial glow is an exciting pregnancy symptom, and it's due to hormonal changes and increased blood flow to your skin, which gives you a rosier, brighter look. Enjoy this pleasant symptom while it lasts.

Faster growing finger and toenails are another pregnancy symptom to expect. Pregnancy hormones are responsible for your nail changes. You may find that your nails are growing faster than ever before. Alternatively, some women experience more brittle nails when pregnant. Nail changes are normal and temporarily. They go away after your baby is born.

Feeling your baby move might begin now for second or third time mothers. (For first-time mothers, they won't feel their baby's little flutters until 17 weeks pregnant.) When you first feel your baby's movements in utero, it may feel like someone is tapping on your womb, or butterflies in your stomach. Enjoy these sensations!

Nasal congestion can be a troublesome pregnancy symptom. You may find that your nose is always runny or stuffy, and you don't have a cold or allergies. Nasal congestion affects up to 30 percent of all expecting women, and it's called rhinitis of pregnancy. It's caused by elevated levels of estrogen causing the mucous membranes to swell.

Increased vaginal discharge is a normal symptom to expect. Since there is more blood flow to your genitals and increased estrogen levels in your body, it's common for you to have more vaginal discharge in pregnancy than before. Normal vaginal discharge should be odorless or mild in scent.

Weight Gain

Your pregnancy weight gain at 16 weeks pregnant may be anywhere between seven to eight pounds. However, you may have gained more or less by now. Although your recommended pregnancy weight gain is a total of 25 to 35 pounds, don’t fret if you are gaining more than the average woman. Every woman and every pregnancy is different. If you are concerned that you’re gaining too much weight, or not enough pregnancy weight, discuss this with your doctor or healthcare provider. He or she will either help you come up with a game plan to keep your pregnancy weight gain in check.

Baby Section

Growth and Development of Baby

At 16 weeks pregnant, your baby is over 4.5 inches long from crown to rump –which can be compared to the length of a small mango. He or she probably weighs close to 3.5 ounces at this point. In the next few weeks, your little one will double his or her weight and grow several inches from crown to rump!

An exciting development – your baby's facial muscles are developed enough that your future child can grimace, frown, and make other faces in the womb. Although your baby has no control over his or her expressions right now, this will change in the weeks ahead.

Your baby's fingers are distinct and separate from the others. However, the fingers remain rather short. Your little one has more control over his hands and can even suck his or her thumb!

The baby's toes are getting longer this week. The arch of your little one’s feet is starting to take shape.

Your baby's hair is starting to grow. While you won't be able to tell his or her hair color until after birth, this is still an interesting development. Even if your baby is born with a full head of hair, his or her hair may fall out and change colors completely within the first few months of life.

Do you remember from last week that your baby's head was still relatively large compared to his body? That's no longer the case! For the first time in your pregnancy, your baby's body is longer than his head. Your little bundle of joy is getting more proportional with each passing day.

The umbilical cord is firmly attached to his or her belly at this point. The umbilical cord provides vital nutrients to your baby.

Your baby's skin continues to be transparent and see-through. There is little underlying fat underneath the skin.

From now onward, your baby will be focusing his or her attention on complicated circulatory matters. For example, your little bundle of joy's heart is pumping around 25 quarts of blood every day. That's pretty impressive for someone that's smaller than a grapefruit!

Pregnancy Health Section

What to Expect at Your Prenatal Visit

Learn all about your pregnancy and baby's development at week 16.

At 16 weeks pregnant, you should be having another prenatal visit with your doctor or healthcare provider. You may have to give urine, have your blood pressure measured, and your baby's heart rate will be monitored. If you did not have a nuchal translucency scan (a first trimester screening test that measures your baby's risk of Down syndrome and other problems) at your last prenatal visit, you may undergo a blood test at this visit. This blood test may be a triple or quadruple screening test.

This prenatal visit is a great time to discuss any questions or concerns you may have with your doctor about the testing.

Second Trimester Screening Tests: Alpha-Fetoprotein (AFP) Test

Prenatal Tests at 16 Weeks Pregnant

Between 16 weeks and 18 weeks pregnant, you will undergo a routine screening test called an alpha-fetoprotein (AFP) test. This is a simple blood test that screens your risk of carrying a baby with certain genetic abnormalities.These include:

  • Neural tube defects, such as spina bifida.

  • Chromosomal abnormalities, such as Down syndrome or Edwards syndrome.

  • Abdominal wall defects in the baby.

What Does the AFP Test Measure?
An AFP test measures the level of alpha-fetoprotein in your bloodstream. AFP is a substance that is produced from your baby and a small amount crosses the placenta and enters your blood stream. Abnormal levels of AFP - either too much or too little AFP, compared to normal levels - can indicate that you are carrying a baby with certain birth defects.

The alpha-fetoprotein (AFP) test is part of the multiple marker screening test (also called triple or quadruple screening). When your blood sample is taken for an AFP test, it will be sent to a lab for analysis. The lab will not only check your AFP levels, but they will also examine the level of the following hormones in your blood: estriol, human chorionic gonadotropin (hCG), and inhibin-A.

What Does an Abnormal Result Mean?
When the levels of AFP and these hormones are abnormal, it indicates that you are at risk for carrying a baby with a chromosomal problem or a birth defect.

Keep in mind that the AFP test and multiple marker screening are screening tests. They are not diagnostic tests. These blood tests only tell you that you are at risk for a baby not a birth defect. It does not diagnose your baby with a certain disorder.

If you receive an abnormal AFP result, your doctor may suggest further testing, including diagnostic tests (such as an amniocentesis) to determine if there is a problem with your baby.

How Accurate is the AFP Blood Test?
Although the AFP blood test is fairly precise, it is not always 100 percent accurate. There are many factors that can skew the results and give you false results.

The lab must take these factors into consideration to get the most accurate result:

  • Gestational age: Although the alpha-fetoprotein test can be performed anytime between 15 and 20 weeks of gestation, you will get the most accurate results between 16 and 18 weeks pregnant.

  • Maternal weight: Your weight affects the dilution of AFP in your blood. If your weight is not measured and reported correctly, this can skew your blood test results.

  • Diabetes: Women who are diabetics are at higher risk for neural tube defects, and the level of AFP in their blood is 15 percent lower than in non-diabetics. For this reason, to get the accurate result, the level of what is "normal AFP" must be lowered.

  • Multiple pregnancy: When you are carrying twins or multiples, you will have an elevated AFP level.

  • Race: Your race also plays a role in your results. The level of AFP in African-Americans is 10 percent higher than in other races.

  • Fetal Death: If your unborn baby has died in utero, this will increase the level of AFP in your blood.

In some cases, you may have an elevated level of AFP in your blood that can't be explained. These unexplained cases are associated with an increased risk of fetal death (miscarriage or stillborn). Your risk increases if you have hypertension.

Who Takes the AFP Blood Test?
In the second trimester of pregnancy, especially at 16 weeks pregnant, all women will be offered an AFP test. Some states require you to undergo this screening test. However, this test is especially recommended for older mothers (35 and up), women who abused drugs or harmful medications during pregnancy, and women with a history of birth defects in their family.

The Risks Associated with Advanced Maternal Age

Advanced Maternal Age and its Risks.

In today's society, more and more women are deciding to delay pregnancy until they reach a stage in life in which they are more settled in their personal lives and in their career. More women are waiting until after age 35 to conceive.

The good news is that most women can continue to have and deliver healthy babies after age 35. However, it may be harder to get pregnant. Your fertility declines as you age.

If you end up conceiving after age 35, your pregnancy may be considered "high risk," because you are twice as likely to develop high blood pressure, gestational diabetes, and preeclampsia (hypertension and protein in the urine). Older women (defined as 35 and older) are also more likely to have twins or multiples. Placental problems, such as placenta previa (a condition in which your placenta covers part or the entire opening of your uterus), are more common in older women.

Women who get pregnant after age 35 are at higher risk of preterm labor (a baby born before 37 weeks pregnant) and delivering a baby that has a low birth weight (less than 5.5 pounds).

In addition, if you are over 35, you are at higher risk of having a baby with genetic defects. The risk of chromosomal disorders (such as Down syndrome) increases with age. For example, a 30-year-old woman generally has a 1 in 1,000 chance of giving birth to a baby with Down syndrome. If you are age 35, your risk increases to 1 in 400 and by age 40, your odds increase to 1 in 100.

If you are over 35 years old, your healthcare provider may recommend that you undergo genetic testing to rule out any genetic or chromosomal problems with your baby.

While all of these risks may sound scary, your healthcare provider will work closely with you to ensure the health of you and your baby. You should keep in mind that most women over age 35 will go on to have healthy babies.

What is a Second Trimester Miscarriage?

At 16 weeks pregnant, your miscarriage risk is very low. Eighty percent of miscarriages occur in the first trimester, or within the first 13 weeks of pregnancy. While second trimester miscarriages can occur, they are rare. Now that you are at pregnancy week 16, your risk of losing your baby is less than 0.6 percent.

Although second trimester miscarriages are uncommon, they are often devastating to the women that they impact. Heavy smoking, moderate to high alcohol consumption, and cocaine and drug abuse can all cause a second trimester miscarriage. However, most of the time, women who experience second trimester miscarriages live a healthy lifestyle.

Second trimester pregnancy losses can be caused by a number of factors, such as problems with the woman's uterus, a weakened cervix that opened (dilated) too soon, chromosomal defects in the baby, and maternal infections.

In rare cases, trauma from diagnostic tests (such as an amniocentesis and chorionic villus sampling) can cause miscarriage. These tests come with a 1 percent miscarriage risk.

Here is what does not cause a miscarriage: exercise, working during pregnancy, or taking birth control pills before pregnancy. All of these lifestyle choices will not impact your risk of miscarriage at all!

Warning signs that a miscarriage may occur include heavy or persistent bleeding that is accompanied with abdominal pain and cramping, a gush of fluid from your vagina with no bleeding or bleeding, and passed fetal tissue. If you experience any of these symptoms during pregnancy week 16, call your doctor immediately.

Try not to worry about having a miscarriage. Your risk is very low, and it will continue to decrease as you go through your pregnancy. (next week)


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