$Unique_ID{PAR00414} $Pretitle{} $Title{Pregnancy: The First Trimester: Special Situations} $Subtitle{} $Author{ Editors of Consumer Guide Ellis, Jeffrey W Ellis, Maria} $Subject{First Trimester Special Situations pregnancy After 35 30s 40s Career education health care contraception Infertility ovulate ovulations ovulation reproductive organs endometriosis endometrial tissue uterus uterine fibroid fibroids Chronic Illness Illnesses high blood pressure diabetes glandular hypothyroidism thyroid gland miscarriages miscarriage stillbirth stillbirths Birth Defect Defects chromosome abnormalities chromosomes abnormality genetic Down's syndrome mentally retarded Complication Complications preeclampsia Placental abruption placenta uterine twin twins cesarean section prenatal care amniocentesis ultrasound amniotic fluid} $Log{ Amniocentesis*0041401.tif} Miracle of Birth The First Trimester: Special Situations Pregnancy After 35 The woman who delayed pregnancy until she was in her 30s or 40s was the exception years ago. Today, however, it is increasingly common for a woman to bear her first child when she is in the third or fourth decade of her life. Career plans, pursuit of education, improved health care, and more reliable forms of contraception are but a few of the factors contributing to the trend of delayed childbearing. By medical tradition, an "older" mother is defined as a woman who becomes pregnant when she is 35 years of age or older. Today, however, authorities agree that there is no reason for a woman over the age of 35 who has not reached menopause to give up the idea of pregnancy merely by reason of her age. Although most pregnant women over the age of 35 will experience successful pregnancies and deliver healthy babies, there are some problems that are more likely to occur in the older mother. Infertility The inability to become pregnant--called infertility--is more common among older women. Because women begin to ovulate (produce eggs) less frequently at about age 30, the number of opportunities to achieve fertilization decreases as each year goes by. For example, the average healthy woman at age 30 will ovulate 13 times a year; by the time she has reached 40, she may ovulate only five or six times a year. Older women are also more likely to have problems with their reproductive organs that may prevent pregnancy. Extensive endometriosis (a condition in which endometrial tissue from the lining of the uterus becomes detached and grows in the abdominal cavity outside the uterus) and uterine fibroids (solid, noncancerous tumors that grow within the walls of the uterus or outward from the uterine wall) may make it difficult or impossible to become pregnant. Chronic Illness As we grow older, we are more likely to develop chronic illnesses, such as high blood pressure, diabetes, and glandular disorders like hypothyroidism (underactive thyroid gland). Although these illnesses can usually be controlled fairly easily in the nonpregnant woman, they may become more serious or even uncontrollable during pregnancy and thus threaten the well-being of both mother and baby. What's more, certain chronic illnesses of the mother are associated with an increased risk of miscarriage and stillbirth. For these reasons, doctors suggest that if you are over the age of 35 and wish to become pregnant, it is best to get a thorough medical checkup before you attempt to conceive. If certain chronic illnesses are detected, they can be completely evaluated and brought under control before pregnancy. If you are over 35 and are currently pregnant, be sure to discuss with your doctor any chronic illnesses you may have. Your condition will be monitored more closely during pregnancy, and special precautions, such as bed rest, can be taken to help prevent further complications (see The Second Trimester: Special Situations, for more on chronic illness in pregnancy). Birth Defects Older mothers are also at greater risk of having babies with severe birth defects caused by abnormalities in the baby's chromosomes. Chromosomes are structures contained within all cells of the body, including the egg and the sperm. These chromosomes contain the genetic information that is passed on from parents to baby. Normally, the sperm and the egg each contain 23 chromosomes. When the sperm and the egg join, the resulting cell, which will develop to form the baby, will contain the normal chromosome number of 46. In some cases, however, the resulting fertilized egg contains 47 chromosomes--an abnormal number. The baby that results will then have 47 chromosomes in most or all of the cells in her body. In many cases, a fetus with an abnormal chromosome number will miscarry, accounting somewhat for the higher miscarriage rate in older women. In those pregnancies that continue, the fetus will usually be born with any one of a number of physical or mental abnormalities. The most common condition associated with an abnormal chromosome number is Down's syndrome. Babies born with this condition are mentally retarded and may have serious abnormalities of the heart and digestive system. Children with Down's syndrome have a characteristic facial appearance marked by slanted eyes, heavy eyebrows, and a large, thick tongue. Although Down's syndrome can occur in babies born to mothers of any age, it occurs more frequently in babies born to older mothers. At the age of 20, a mother has one chance in 1,667 of having a child with Down's syndrome; at the age of 35, she has one chance in 370; at age 40, she has one chance in 109. Although the father's age may have some effect on risk, it is much less significant than the effect of the mother's age. If you have any questions about the effect your age or your husband's age may have on your baby, be sure to discuss them with your doctor. Complications in Pregnancy, Labor, or Delivery During pregnancy, the older mother may experience more aches and pains, such as backache and leg pain, due to "aging" of her bones and muscles. Beyond these minor discomforts, however, the older woman is at a somewhat higher risk of developing certain potentially serious complications. An older woman, for example, is more likely than a younger woman to develop severely elevated blood pressure (preeclampsia) during pregnancy. Placental abruption, in which the placenta becomes detached from the uterine wall before the baby is born, is also more common among older mothers. Placental abruption can lead to severe bleeding in the mother and oxygen deprivation in the baby. For unknown reasons, the older mother is also more likely to have twins. Most older mothers experience a normal labor and delivery. Because certain complications are more common among older women, however, the rate of cesarean section is somewhat higher in older mothers. Even though pregnancy in older women is associated with an increase in certain complications, it's important to keep in mind that the majority of older mothers deliver healthy babies. As in any pregnancy, good prenatal care can help the older mother decrease her risk of experiencing complications and greatly increase the chances that her baby will be born healthy. Prenatal Care for the Older Mother The prenatal care of an older mother is generally like that of a woman in any other age group. It involves proper diet and weight gain, adequate exercise and rest, and careful monitoring through prenatal visits. If the mother has a history of high blood pressure, diabetes, or other chronic disorders, prenatal office visits may be more frequent than usual, especially during the last two months of pregnancy. In addition to this basic prenatal care, mothers 35 years of age and older will be offered amniocentesis--a test to determine the presence of chromosome abnormalities in the baby. This test is performed between the sixteenth and eighteenth weeks of pregnancy. Immediately before performing an amniocentesis, an ultrasound study (see The Fourth Month: Ask The Doctor) is performed to determine the exact location of both the baby and the placenta. After an area of skin on the mother's abdomen has been anesthetized, the doctor inserts a long, hollow needle through the mother's abdominal wall and into the uterus (the ultrasound study helps the doctor to insert the needle without harming the baby). With the needle in the amniotic sac surrounding the baby, the doctor draws about two tablespoons of amniotic fluid into a syringe. This fluid contains cells that have fallen off the skin of the baby. After these cells have been grown on a special culture plate and examined under a microscope, the chromosomes of the baby are analyzed to see if there is an abnormal number.