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8.5: Health and Risks in Pregnancy
Opening the book…
Trimesters of Pregnancy
Pregnancy typically lasts about 40 weeks, calculated from the first day of the last menstrual period, or about 280 days. However, pregnancy is divided into three trimesters, each lasting about three months, to track the physical and developmental changes in both the mother and the baby. The first trimester spans from conception to 12 weeks, the second trimester from 13 to 26 weeks, and the third trimester from 27 weeks until birth. These divisions focus on maternal symptoms and fetal growth milestones. In contrast, prenatal stages—germinal, embryonic, and fetal stages—are based on biological development and are used to describe the developing organism in greater detail.
Gestational Age
Most mothers-to-be will keep track of the age of a pregnancy, or gestational age. Gestational age is also used to determine the timing of prenatal assessments, assess milestones, track fetal growth, and make delivery decisions as needed. It is common to hear vocabulary related to gestational age and how the pregnancy may be classified, particularly if early delivery occurs, due to the types of interventions that may be necessary to ensure the best outcomes for the baby.
Table \(\PageIndex{1}\): Gestational Age and Pregnancy Classification
Classification
Gestational Age
Description
Micropreemie
Less than 26 weeks
Babies born at extremely early gestational ages require advanced medical care and have high risks.
Very Preterm
26-31 weeks
Babies born significantly early often face developmental challenges and require intensive medical support.
Moderate Preterm
32-33 weeks
Babies born moderately early typically need some neonatal care.
Late Preterm
34-36 weeks
Babies born close to term may still face challenges like jaundice or feeding issues.
Early Term
37-38 weeks, 6 days
Babies born just before full term are generally healthy but may have a slightly higher risk of complications.
Full Term
39-40 weeks, 6 days
Optimal timing for delivery; babies are fully developed and have the best outcomes for health and growth.
Late Term
41 weeks - 41 weeks, 6 days
Babies born slightly past their due date are typically healthy but monitored for signs of complications.
Postterm
42 weeks or more
Babies born well past the due date may face risks like reduced amniotic fluid or larger birth weight.
Prenatal Assessment
A number of assessments are suggested for women as part of their routine prenatal care to find conditions that may increase the risk of complications for the mother and fetus (Eisenberg, Murkoff, & Hathaway, 1996). These can include blood and urine analyses, screening, and diagnostic tests for birth defects.
Figure \(\PageIndex{1}\): A woman receiving an ultrasound. Image by MedicalPrudens is licensed under CC0 1.0.
Ultrasound is one of the primary screening tests used in conjunction with blood tests. The ultrasound is a test in which sound waves are used to examine the fetus. There are two general types. Transvaginal ultrasounds are used in early pregnancy, while transabdominal ultrasounds are more common and used after 10 weeks of pregnancy (typically, 16 to 20 weeks).
Ultrasounds are used to check the fetus for defects or problems. It can also determine the age of the fetus, the location of the placenta, the fetal position, movement, breathing, and heart rate, as well as the amount of amniotic fluid in the uterus and the number of fetuses. Most women have at least one ultrasound during pregnancy, but if problems are noted, additional ultrasounds may be recommended.
When diagnosis of a birth defect is necessary, ultrasounds help guide the more invasive diagnostic tests of amniocentesis and chorionic villus sampling. Amniocentesis is a procedure in which a needle is used to withdraw a small amount of amniotic fluid and cells from the sac surrounding the fetus, which are later tested.
Figure \(\PageIndex{2}\): Amniocentesis. Image by BruceBlaus is licensed under CC BY-SA 4.0.
Chorionic Villus Sampling is a procedure in which a small sample of cells is taken from the placenta and tested. Both amniocentesis and chorionic villus sampling have a risk of miscarriage, and consequently, they are not done routinely. 61
Complications of Pregnancy
There are a number of common side effects of pregnancy. Not everyone experiences all of these, nor to the same degree. Although they are considered minor, this does not mean that these problems are not potentially very uncomfortable. These side effects include nausea (particularly during the first 3-4 months of pregnancy as a result of higher levels of estrogen in the system), heartburn, gas, hemorrhoids, backache, leg cramps, insomnia, constipation, shortness of breath or varicose veins (as a result of carrying a heavy load on the abdomen). These are minor issues.
But there are also serious complications of pregnancy which can pose health risks to mother and child, and that often require hospitalization.
Hyperemesis gravidarum is characterized by severe nausea, vomiting, weight loss, and possibly dehydration. Signs and symptoms may also include vomiting many times a day and feeling faint. The exact causes of hyperemesis gravidarum are unknown. Risk factors include the first pregnancy, multiple pregnancy, obesity, prior or family history of HG, trophoblastic disorder, and a history of eating disorders. Treatment includes drinking fluids and a bland diet. Medication, intravenous fluids, and hospitalization may be required. Hyperemesis gravidarum is estimated to affect 0.3–2.0% of pregnant women. Those affected have a low risk of miscarriage but a higher risk of premature birth.
Ectopic Pregnancy occurs when the zygote becomes attached to the fallopian tube before reaching the uterus. About 1 in 50 pregnancies in the United States are tubal pregnancies, and this number has been increasing because of the higher rates of pelvic inflammatory disease and Chlamydia (Carroll, 2007). Abdominal pain, vaginal bleeding, nausea and fainting are symptoms of ectopic pregnancy.
Figure \(\PageIndex{3}\): An ectopic pregnancy. Image by Takatakatakumi is licensed under CC BY-SA 3.0.
Spontaneous abortion is experienced in an estimated 20-40 percent of undiagnosed pregnancies and in another 10 percent of diagnosed pregnancies. Usually, the body aborts due to chromosomal abnormalities, and this typically happens before the 12th week of pregnancy. Cramping and bleeding result, and normal periods return after several months. Some women are more likely to have repeated miscarriages due to chromosomal, amniotic, or hormonal problems, but miscarriage can also be a result of defective sperm (Carrell et. al., 2003).
Preeclampsia, also known as Toxemia, is characterized by a sharp rise in blood pressure, protein leakage into the urine due to kidney problems, and swelling of the hands, feet, and face during the third trimester of pregnancy. Preeclampsia is the most common complication of pregnancy. When preeclampsia causes seizures, the condition is known as eclampsia, which is the second leading cause of maternal death in the United States. Preeclampsia is also a leading cause of fetal complications, which include low birth weight, premature birth, and stillbirth. Treatment typically involves bed rest and, in some cases, medication. If this treatment is ineffective, labor may be induced.
Maternal Mortality: Approximately 1000 women die in childbirth around the world each day (World Health Organization, 2010). Rates are highest in Sub-Saharan Africa and South Asia, although there has been a substantial decrease in these rates. The campaign to make childbirth safe for everyone has led to the development of clinics accessible to those living in more remote areas and the training of more midwives to assist in childbirth.63
Infertility and Building Families
Infertility
When a couple has failed to conceive a child in a year, they receive the diagnosis of infertility. Infertility affects about 10 to 15 percent of couples in the United States (Mayo Clinic, 2015). Male factors create infertility in about a third of the cases. For men, the most common cause is a lack of sperm production or low sperm production.
Female factors cause infertility in another third of cases. For women, one of the most common causes of infertility is the failure to ovulate. Another cause of infertility in women is Pelvic Inflammatory Disease (PID), which is an infection of a woman’s reproductive organs (Carroll, 2007).
Both male and female factors contribute to the remainder of cases of infertility. 64
Options for Building Families
There are numerous options for pursuing parenthood and building families. Let’s briefly explore some of these.
Assisted Reproductive Technology Assisted reproductive technology (ART) is the technology used to achieve pregnancy in procedures such as fertility medication (to stimulate ovulation), surgical procedures, artificial insemination IUI), in vitro fertilization (IVF), and surrogacy. These options are available for people who are experiencing infertility or cannot conceive children naturally (which also includes single parents, and gay/lesbian couples). 65
Intrauterine insemination (IUI) is a type of artificial insemination that involves the placement of sperm directly into the uterus at the time of ovulation, either in a natural menstrual cycle or following ovarian stimulation. 66
In vitro fertilization (IVF): IVF generally starts with stimulating the ovaries to increase egg production. Most fertility medications are agents that stimulate the development of follicles in the ovary. Examples are gonadotropins and gonadotropin-releasing hormone. After stimulation, the physician surgically extracts one or more eggs from the ovary and unites them with sperm in a laboratory setting, with the intent of producing one or more embryos. Fertilization occurs outside the body, and the fertilized egg is reinserted into the woman's reproductive tract through a procedure called embryo transfer. 67
Figure \(\PageIndex{4}\): The IVF process. Image by Manu5 is licensed under CC BY-SA 4.0.
Donor Gametes & Embryos: People can also use sperm, ova (eggs), and embryos from donors in conjunction with ART. These donations occur through agencies and donor banks or between private individuals. In the U.S., donors can be compensated for their donations.
Surrogacy: In surrogacy, one woman (surrogate mother) carries a child for another person/s (commissioning person/couple), based on a legal agreement before conception, requiring the child to be relinquished to the commissioning person/couple following birth. There are different types of surrogacy, which relate to whether or not the ova used to conceive the child are her own (traditional surrogacy) or not (gestational surrogacy). 69
Adoption: People can also choose to pursue adoption to build their families (with or without experiencing infertility). Adoption can take place through the foster care system, privately, or through agencies. Adoptions can be either domestic (within the United States) or international. And they can be open (with differing amounts of contact between biological/birth families and adoptive families) or closed.
Family Built with Surrogacy
Figure \(\PageIndex{5}\): This same-sex couple used a surrogate. Photo by Daryn Crawford used with permission.
Family Built through Adoption
Figure \(\PageIndex{6}\): This single mother adopted her daughter. Photo by Michaela Szidloski used with permission.
References, Contributors and Attributions
Carrell, D. T., Wilcox, A. L., Lowry, L., Peterson, C. M., Jones, K. P., & Erikson, L. (2003). Elevated sperm chromosome aneuploidy and apoptosis in patients with unexplained recurrent pregnancy loss. Obstetrics and Gynecology, 101(6), 1229-1235.
Carroll, J. L. (2007). Sexuality now: Embracing diversity (2nd ed.). Belmont, CA: Thomson.
Eisenberg, A., Murkoff, H. E., & Hathaway, S. E. (1996). What to expect when you’re expecting. New York: Workman Publishing.
World Health Organization. (2010, September 15). Maternal deaths worldwide drop by a third, WHO. Retrieved from http://www.who.int/mediacentre/news/releases/ 2010/maternal_mortality_20100915/en/index.html