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2.5: Conception, Pregnancy, and Birth

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    Learning Outcomes

    • Analyze psychosocial and cultural factors impacting abortion, pregnancy and the birthing process and discuss best practices to promote equity within healthcare systems.
    • Demonstrate an understanding of the process of conception including:
      • how to enhance the possibility of conception
      • infertility problems and how they might be dealt with
      • spontaneous and elective abortion
      • aspects of a healthy pregnancy
      • sexual interaction during pregnancy
      • stages of childbirth
      • psychological and sexual adjustments postpartum


    This week’s reading is all about conception, pregnancy and birth. Much of the content we’ll be covering will be physiological, in nature. However, as you go through the material, please keep your intersectional lens on. For example, when we’re discussing the biology of fertilization, how might environmental conditions influence the process (conception through intercourse versus IVF). Or perhaps when we consider pregnancy, how might socio-economic status and/or race impact folks’ access to prenatal care? And when we address issues of birth, note the disparity in how everything from pain care to maternal and infant mortality impact BIPOC. As with many of these topics in human sexuality, we can marvel at the complexities and wonder of our bodies and their many responses. At the same time, we can challenge the areas in which culture, race, poverty, ethnicity, abilities, and marginalization can impede some people’s opportunities.

    One more note

    This chapter is very much a work-in-progress. One of the challenges we’ve had authoring this chapter is finding the balance of maintaining the respectful and safe space that pregnancy and birthing has afforded generations of women. This is especially true for BIPOC communities that push back against dominant, white, medical establishments. At the same time, we seek to broaden the language, awareness, and understanding of pregnancy and birth, since so much of the traditional, western approaches have excluded gender-diverse people and families. In that vein, we are embracing the and; that is- we’re striving to consistently honor our foremothers and visionaries of birth who’ve held safe space for women, as well as respectfully embrace our non-binary, trans, and gender-diverse families in the amazing process of pregnancy and birth.


    Fertilization occurs when a sperm and an oocyte (egg) combine and their nuclei fuse. Because each of these reproductive cells is a haploid cell containing half of the genetic material needed to form a human being, their combination forms a diploid cell. This new single cell, called a zygote, contains all of the genetic material needed to form a human—half from the egg and half from the sperm.

    Transit of Sperm

    Fertilization is a numbers game. During ejaculation, hundreds of millions of sperm (spermatozoa) are released into the vagina. Almost immediately, millions of these sperm are overcome by the acidity of the vagina, and millions more may be blocked from entering the uterus by thick cervical mucus. Of those that do enter, thousands are destroyed by phagocytic uterine leukocytes. Thus, the race into the uterine tubes, which is the most typical site for sperm to encounter the oocyte, is reduced to a few thousand contenders. Their journey—thought to be facilitated by uterine contractions—usually takes from 30 minutes to 2 hours. If the sperm do not encounter an oocyte immediately, they can survive in the uterine tubes for another 3–5 days. Thus, fertilization can still occur if intercourse takes place a few days before ovulation. In comparison, an oocyte can survive independently for only approximately 24 hours following ovulation. Intercourse more than a day after ovulation will therefore usually not result in fertilization.

    During the journey, fluids in the female reproductive tract prepare the sperm for fertilization through a process called capacitation, or priming. The fluids improve the motility of the spermatozoa. They also deplete cholesterol molecules embedded in the membrane of the head of the sperm, thinning the membrane in such a way that will help facilitate the release of the lysosomal (digestive) enzymes needed for the sperm to penetrate the oocyte’s exterior once contact is made. Sperm must undergo the process of capacitation in order to have the “capacity” to fertilize an oocyte. If they reach the oocyte before capacitation is complete, they will be unable to penetrate the oocyte’s thick outer layer of cells.

    Contact Between Sperm and Oocyte

    Upon ovulation, the oocyte released by the ovary is swept into—and along—the uterine tube. Fertilization must occur in the distal uterine tube because an unfertilized oocyte cannot survive the 72-hour journey to the uterus.

    As it is swept along the distal uterine tube, the oocyte encounters the surviving capacitated sperm, which stream toward it in response to chemical attractants released by the cells of the corona radiata. To reach the oocyte itself, the sperm must penetrate the two protective layers. Eventually, a single sperm makes contact with sperm-binding receptors on the oocyte’s plasma membrane. The plasma membrane of that sperm then fuses with the oocyte’s plasma membrane, and the head and mid-piece of the “winning” sperm enter the oocyte interior.

    How do sperm penetrate the corona radiata? As you can see, the first sperm to reach the oocyte is never the one to fertilize it. Rather, hundreds of sperm cells must undergo the acrosomal reaction, each helping to degrade the corona radiata and zona pellucida until a path is created to allow one sperm to contact and fuse with the plasma membrane of the oocyte. If you consider the loss of millions of sperm between entry into the vagina and degradation of the zona pellucida, you can understand why a low sperm count can cause infertility.

    One or more interactive elements has been excluded from this version of the text. You can view them online here:

    The Zygote

    Most of the time, a single egg is released during an ovulation cycle. However, in approximately 1 percent of ovulation cycles, two eggs are released and both are fertilized. Two zygotes form, implant, and develop, resulting in the birth of dizygotic (or fraternal) twins. Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at different times.

    Much less commonly, a zygote can divide into two separate offspring during early development. This results in the birth of monozygotic (or identical) twins. Although the zygote can split as early as the two-cell stage, splitting occurs most commonly during the early blastocyst stage, with roughly 70–100 cells present. These two scenarios are distinct from each other, in that the twin embryos that separated at the two-cell stage will have individual placentas, whereas twin embryos that form from separation at the blastocyst stage will share a placenta and a chorionic cavity.

    In Vitro Fertilization

    IVF, which stands for in vitro fertilization, is an assisted reproductive technology. In vitro, which in Latin translates to “in glass,” refers to a procedure that takes place outside of the body. There are many different indications for IVF. For example, someone may produce normal eggs, but the eggs cannot reach the uterus because the uterine tubes are blocked or otherwise compromised. There are also challenges with low sperm count, low sperm motility, sperm with an unusually high percentage of morphological abnormalities, or sperm that are incapable of penetrating the zona pellucida of an egg.

    A typical IVF procedure begins with egg collection. A normal ovulation cycle produces only one oocyte, but the number can be boosted significantly (to 10–20 oocytes) by administering a short course of gonadotropins. The course begins with follicle-stimulating hormone (FSH) analogs, which support the development of multiple follicles, and ends with a luteinizing hormone (LH) analog that triggers ovulation. Right before the ova would be released from the ovary, they are harvested using ultrasound-guided oocyte retrieval. In this procedure, ultrasound allows a physician to visualize mature follicles. The ova are aspirated (sucked out) using a syringe.

    In parallel, sperm are obtained from a partner or from a sperm bank. The sperm are prepared by washing to remove seminal fluid because seminal fluid contains a peptide, FPP (or, fertilization promoting peptide), that—in high concentrations—prevents capacitation of the sperm. The sperm sample is also concentrated, to increase the sperm count per milliliter.

    Next, the eggs and sperm are mixed in a petri dish. The ideal ratio is 75,000 sperm to one egg. If there are severe problems with the sperm—for example, the count is exceedingly low, or the sperm are completely nonmotile, or incapable of binding to or penetrating the zona pellucida—a sperm can be injected into an egg. This is called intracytoplasmic sperm injection (ICSI).

    “IVF Capillary Tube Insertion” by ZEISS Microscopy is licensed under CC BY-NC-ND 2.0.

    The embryos are then incubated until they either reach the eight-cell stage or the blastocyst stage. In the United States, fertilized eggs are typically cultured to the blastocyst stage because this results in a higher pregnancy rate. Finally, the embryos are transferred to the uterus using a plastic catheter (tube).

    IVF is a relatively new and still evolving technology, and until recently it was necessary to transfer multiple embryos to achieve a good chance of a pregnancy. Today, however, transferred embryos are much more likely to implant successfully, so countries that regulate the IVF industry cap the number of embryos that can be transferred per cycle at two. This reduces the risk of multiple-birth pregnancies.


    Pregnancy begins with the fertilization of an egg and continues through to the birth of the individual. The length of time of gestation varies among animals, but is very similar among the great apes: human gestation is 266 days, while chimpanzee gestation is 237 days, a gorilla’s is 257 days, and orangutan gestation is 260 days long. The fox has a 57-day gestation. Dogs and cats have similar gestations averaging 60 days. The longest gestation for a land mammal is an African elephant at 640 days. The longest gestations among marine mammals are the beluga and sperm whales at 460 days.

    Twenty-four hours before fertilization, the egg has finished meiosis and becomes a mature oocyte. When fertilized (at conception) the egg becomes known as a zygote. The zygote travels through the oviduct to the uterus. The developing embryo must implant into the wall of the uterus within seven days, or it will deteriorate and die. The outer layers of the zygote (blastocyst) grow into the endometrium by digesting the endometrial cells, and wound healing of the endometrium closes up the blastocyst into the tissue. Another layer of the blastocyst, the chorion, begins releasing a hormone called human beta chorionic gonadotropin (β-HCG) which makes its way to the corpus luteum and keeps that structure active. This ensures adequate levels of progesterone that will maintain the endometrium of the uterus for the support of the developing embryo. Pregnancy tests determine the level of β-HCG in urine or serum. If the hormone is present, the test is positive.

    By Ttrue12 – Own work, CC BY-SA 3.0,

    The gestation period is divided into three equal periods or trimesters. During the first two to four weeks of the first trimester, nutrition and waste are handled by the endometrial lining through diffusion. As the trimester progresses, the outer layer of the embryo begins to merge with the endometrium, and the placenta forms. This organ takes over the nutrient and waste requirements of the embryo and fetus, with the parent’s blood passing nutrients to the placenta and removing waste from it.

    First Trimester

    Internal organs and body structures begin to develop during the first trimester. By five weeks, limb buds, eyes, the heart, and liver have been basically formed. By eight weeks, the term fetus applies, and the body is essentially formed, as shown in Figure 15.4. The individual is about five centimeters (two inches) in length and many of the organs, such as the lungs and liver, are not yet functioning. Exposure to any toxins is especially dangerous during the first trimester, as all of the body’s organs and structures are going through initial development. Anything that affects that development can have a severe effect on the fetus’ survival.

    Figure 15.4 Fetal development is shown at nine weeks gestation. (Credit: Ed Uthman)

    Second Trimester

    During the second trimester, the fetus grows to about 30 cm (12 inches), as shown in Figure 15.5. It becomes active and the mother usually feels the first movements. All organs and structures continue to develop. The placenta has taken over the functions of nutrition and waste and the production of estrogen and progesterone from the corpus luteum, which has degenerated. The placenta will continue functioning up through the delivery of the baby.

    Figure 15. 5 This fetus is just entering the second trimester, when the placenta takes over more of the functions performed as the baby develops. (Credit: National Museum of Health and Medicine)

    Third Trimester

    During the third trimester, the fetus grows to 3 to 4 kg (6 ½ -8 ½ lbs.) and about 50 cm (19-20 inches) long, as illustrated in Figure 15.6. This is the period of the most rapid growth during the pregnancy. Organ development continues to birth (and some systems, such as the nervous system and liver, continue to develop after birth).

    Figure 15.6 There is rapid fetal growth during the third trimester.

    (Credit: modification of work by Gray’s Anatomy)

    Maternal Changes During Pregnancy

    A full-term pregnancy lasts approximately 270 days (approximately 38.5 weeks) from conception to birth. Because it is easier to remember the first day of the last menstrual period (LMP) than to estimate the date of conception, obstetricians set the due date as 284 days (approximately 40.5 weeks) from the LMP. This assumes that conception occurred on day 14 of the woman’s cycle, which is usually a good approximation. The 40 weeks of an average pregnancy are usually discussed in terms of three trimesters, each approximately 13 weeks. During the second and third trimesters, the pre-pregnancy uterus—about the size of a fist—grows dramatically to contain the fetus, causing a number of anatomical changes in the mother (Figure 15.7).

    Figure 15.7 Size of Uterus throughout Pregnancy. The uterus grows throughout pregnancy to accommodate the fetus.

    Effects of Hormones

    Virtually all of the effects of pregnancy can be attributed in some way to the influence of hormones—particularly estrogens, progesterone, and hCG. As the placenta develops and the corpus luteum degenerates during weeks 12–17, the placenta gradually takes over as the endocrine organ of pregnancy.

    The placenta converts weak androgens secreted by the maternal and fetal adrenal glands to estrogens, which are necessary for pregnancy to progress. Estrogen levels climb throughout the pregnancy, increasing 30-fold by childbirth. Estrogens have the following actions:

    • They suppress FSH and LH production, effectively preventing ovulation. (This function is the biological basis of hormonal birth control pills.)
    • They induce the growth of fetal tissues and are necessary for the maturation of the fetal lungs and liver.
    • They promote fetal viability by regulating progesterone production and triggering fetal synthesis of cortisol, which helps with the maturation of the lungs, liver, and endocrine organs such as the thyroid gland and adrenal gland.
    • They stimulate maternal tissue growth, leading to uterine enlargement and mammary duct expansion and branching.

    Relaxin, another hormone secreted by the corpus luteum and then by the placenta, helps prepare the mother’s body for childbirth. It increases the elasticity of the symphysis pubis joint and pelvic ligaments, making room for the growing fetus and allowing expansion of the pelvic outlet for childbirth. Relaxin also helps dilate the cervix during labor.

    Weight Gain

    The second and third trimesters of pregnancy are associated with dramatic changes in maternal anatomy and physiology. The most obvious anatomical sign of pregnancy is the dramatic enlargement of the abdominal region, coupled with maternal weight gain. This weight results from the growing fetus as well as the enlarged uterus, amniotic fluid, and placenta. Additional breast tissue and dramatically increased blood volume also contribute to weight gain (Table 15.1). Surprisingly, fat storage accounts for only approximately 2.3 kg (5 lbs) in a normal pregnancy and serves as a reserve for the increased metabolic demand of breastfeeding.

    During the first trimester, the parent does not need to consume additional calories to maintain a healthy pregnancy. However, a weight gain of approximately 0.45 kg (1 lb) per month is common. During the second and third trimesters, the mother’s appetite increases, but it is only necessary for her to consume an additional 300 calories per day to support the growing fetus. Most women gain approximately 0.45 kg (1 lb) per week.

    Contributors to Weight Gain During Pregnancy

    Component Weight (kg) Weight (lb)
    Fetus 3.2–3.6 7–8
    Placenta and fetal membranes 0.9–1.8 2–4
    Amniotic fluid 0.9–1.4 2–3
    Breast tissue 0.9–1.4 2–3
    Blood 1.4 4
    Fat 0.9–4.1 3–9
    Uterus 0.9–2.3 2–5
    Total 10–16.3 22–36

    Table 15.1

    Changes in Organ Systems During Pregnancy

    As the body adapts to pregnancy, characteristic physiologic changes occur. These changes can sometimes prompt symptoms often referred to collectively as the common discomforts of pregnancy.

    Digestive and Urinary System Changes

    Nausea and vomiting, sometimes triggered by an increased sensitivity to odors, are common during the first few weeks to months of pregnancy. This phenomenon is often referred to as “morning sickness,” although the nausea may persist all day. The source of pregnancy nausea is thought to be the increased circulation of pregnancy-related hormones, specifically circulating estrogen, progesterone, and hCG. Decreased intestinal peristalsis may also contribute to nausea. By about week 12 of pregnancy, nausea typically subsides.

    A common gastrointestinal complaint during the later stages of pregnancy is gastric reflux, or heartburn, which results from the upward, constrictive pressure of the growing uterus on the stomach. The same decreased peristalsis that may contribute to nausea in early pregnancy is also thought to be responsible for pregnancy-related constipation as pregnancy progresses.

    The downward pressure of the uterus also compresses the urinary bladder, leading to frequent urination. The problem is exacerbated by increased urine production. In addition, the maternal urinary system processes both maternal and fetal wastes, further increasing the total volume of urine.

    Circulatory System Changes

    Blood volume increases substantially during pregnancy, so that by childbirth, it exceeds its preconception volume by 30 percent, or approximately 1–2 liters. The greater blood volume helps to manage the demands of fetal nourishment and fetal waste removal. In conjunction with increased blood volume, the pulse and blood pressure also rise moderately during pregnancy. As the fetus grows, the uterus compresses underlying pelvic blood vessels, hampering venous return from the legs and pelvic region. As a result, many pregnant women develop varicose veins or hemorrhoids.

    Respiratory System Changes

    During the second half of pregnancy, the respiratory minute volume (volume of gas inhaled or exhaled by the lungs per minute) increases by 50 percent to compensate for the oxygen demands of the fetus and the increased maternal metabolic rate. The growing uterus exerts upward pressure on the diaphragm, decreasing the volume of each inspiration and potentially causing shortness of breath, or dyspnea. During the last several weeks of pregnancy, the pelvis becomes more elastic, and the fetus descends lower in a process called lightening. This typically ameliorates dyspnea.

    The respiratory mucosa swell in response to increased blood flow during pregnancy, leading to nasal congestion and nose bleeds, particularly when the weather is cold and dry. Humidifier use and increased fluid intake are often recommended to counteract congestion.

    Integumentary System Changes

    The dermis (skin) stretches extensively to accommodate the growing uterus, breast tissue, and fat deposits on the thighs and hips. Torn connective tissue beneath the dermis can cause striae (stretch marks) on the abdomen, which appear as red or purple marks during pregnancy that fade to a silvery white color in the months after childbirth.

    An increase in melanocyte-stimulating hormone, in conjunction with estrogens, darkens the areolae and creates a line of pigment from the umbilicus to the pubis called the linea nigra (Figure 15.8). Melanin production during pregnancy may also darken or discolor skin on the face to create a chloasma, or “mask of pregnancy.”

    Figure 15.8 Linea Nigra The linea nigra, a dark medial line running from the umbilicus to the pubis, forms during pregnancy and persists for a few weeks following childbirth. The linea nigra shown here corresponds to pregnancies that are 38 and 22 weeks along.


    Labor is the physical efforts of expulsion of the fetus and the placenta from the uterus during birth (parturition). Toward the end of the third trimester, estrogen causes receptors on the uterine wall to develop and bind the hormone oxytocin. At this time, the baby reorients, facing forward and down with the back or crown of the head engaging the cervix (uterine opening). This causes the cervix to stretch and nerve impulses are sent to the hypothalamus, which signals for the release of oxytocin from the posterior pituitary. The oxytocin causes the smooth muscle in the uterine wall to contract. At the same time, the placenta releases prostaglandins into the uterus, increasing the contractions. A positive feedback relay occurs between the uterus, hypothalamus, and the posterior pituitary to assure an adequate supply of oxytocin. As more smooth muscle cells are recruited, the contractions increase in intensity and force.

    Stages of Childbirth

    The process of childbirth can be divided into three stages: cervical dilation, expulsion of the newborn, and afterbirth (Figure 15.9).

    Cervical Dilation

    For vaginal birth to occur, the cervix must dilate fully to 10 cm in diameter—wide enough to deliver the newborn’s head. The dilation stage is the longest stage of labor and typically takes 6–12 hours. However, it varies widely and may take minutes, hours, or days, depending in part on whether the mother has given birth before; in each subsequent labor, this stage tends to be shorter.

    Figure 15.9 Stages of Childbirth The stages of childbirth include Stage 1, early cervical dilation; Stage 2, full dilation and expulsion of the newborn; and Stage 3, delivery of the placenta and associated fetal membranes. (The position of the newborn’s shoulder is described relative to the mother.)

    True labor progresses in a positive feedback loop in which uterine contractions stretch the cervix, causing it to dilate and efface, or become thinner. Cervical stretching induces reflexive uterine contractions that dilate and efface the cervix further. In addition, cervical dilation boosts oxytocin secretion from the pituitary, which in turn triggers more powerful uterine contractions. When labor begins, uterine contractions may occur only every 3–30 minutes and last only 20–40 seconds; however, by the end of this stage, contractions may occur as frequently as every 1.5–2 minutes and last for a full minute.

    Each contraction sharply reduces oxygenated blood flow to the fetus. For this reason, it is critical that a period of relaxation occur after each contraction. Fetal distress, measured as a sustained decrease or increase in the fetal heart rate, can result from severe contractions that are too powerful or lengthy for oxygenated blood to be restored to the fetus. Such a situation can be cause for an emergency birth with vacuum, forceps, or surgically by Caesarian section.

    The amniotic membranes rupture before the onset of labor in about 12 percent of women; they typically rupture at the end of the dilation stage in response to excessive pressure from the fetal head entering the birth canal.

    Expulsion Stage

    The expulsion stage begins when the fetal head enters the birth canal and ends with birth of the newborn. It typically takes up to 2 hours, but it can last longer or be completed in minutes, depending in part on the orientation of the fetus. The vertex presentation known as the occiput anterior vertex is the most common presentation and is associated with the greatest ease of vaginal birth. The fetus faces the maternal spinal cord and the smallest part of the head (the posterior aspect called the occiput) exits the birth canal first.

    In fewer than 5 percent of births, the infant is oriented in the breech presentation, or buttocks down. In a complete breech, both legs are crossed and oriented downward. In a frank breech presentation, the legs are oriented upward. Before the 1960s, it was common for breech presentations to be delivered vaginally. Today, most breech births are accomplished by Caesarian section.

    Vaginal birth is associated with significant stretching of the vaginal canal, the cervix, and the perineum. Until recent decades, it was routine procedure for an obstetrician to numb the perineum and perform an episiotomy, an incision in the posterior vaginal wall and perineum. The perineum is now more commonly allowed to tear on its own during birth. Both an episiotomy and a perineal tear need to be sutured shortly after birth to ensure optimal healing. Although suturing the jagged edges of a perineal tear may be more difficult than suturing an episiotomy, tears heal more quickly, are less painful, and are associated with less damage to the muscles around the vagina and rectum.

    Upon birth of the newborn’s head, an obstetrician will aspirate mucus from the mouth and nose before the newborn’s first breath. Once the head is birthed, the rest of the body usually follows quickly. The umbilical cord is then double-clamped, and a cut is made between the clamps. This completes the second stage of childbirth.


    The delivery of the placenta and associated membranes, commonly referred to as the afterbirth, marks the final stage of childbirth (Figure 15.10). After expulsion of the newborn, the myometrium continues to contract. This movement shears the placenta from the back of the uterine wall. It is then easily delivered through the vagina. Continued uterine contractions then reduce blood loss from the site of the placenta. Delivery of the placenta marks the beginning of the postpartum period—the period of approximately 6 weeks immediately following childbirth during which the pregnant person’s body gradually returns to a non-pregnant state. If the placenta does not birth spontaneously within approximately 30 minutes, it is considered retained, and the obstetrician may attempt manual removal. If this is not successful, surgery may be required.

    It is important that the obstetrician examines the expelled placenta and fetal membranes to ensure that they are intact. If fragments of the placenta remain in the uterus, they can cause postpartum hemorrhage. Uterine contractions continue for several hours after birth to return the uterus to its pre-pregnancy size in a process called involution, which also allows the abdominal organs to return to their pre-pregnancy locations. Breastfeeding facilitates this process.

    Figure 15.10 Human Afterbirth (Placenta). Public domain, via Wikimedia Commons

    Pregnancy and Birthing Challenges


    Unfortunately, some instances of pregnancy do not end in a healthy birth. Miscarriage, or spontaneous pregnancy loss before 28 weeks of gestation, occurs in up to 20-25 percent of pregnancies (Sohr-Preston, Morain, Chapman, Pardue, & Ford, 2018; Bellhouse, Temple-Smith, & Bilardi, 2018). The majority of these miscarriages tend to occur before 12 weeks of gestation (often before women realize they’re pregnant). Nearly half of all miscarriages have no known cause, leading to widespread misperceptions about frequency. In cases where there is a known cause, half are attributed to chromosomal abnormalities. Consequently, most miscarriages are largely out of the control of the expectant parent. Additionally, most miscarriages do not inform the parent’s past or future success in bringing a baby to full-term (Sohr-Preston, et al, 2018).

    In addition to some confusion regarding prevalence and frequency of miscarriage rates, there are often mixed responses to families impacted by miscarriage from the medical community, the general public, family members and friends. In so many ways, pregnancy loss is a time when many people need emotional support from those around them. There are a number of grass-roots agencies and hospital facilitated programs now in place to support families who’ve experienced loss. Partners are often a huge source of support, but research also identifies the need for more public discourse and education around pregnancy loss generally, which boosts well-being for all members of the families involved (Bellhouse, Temple-Smith, & Bilardi, 2018).


    The issues surrounding abortion, the deliberate termination of a pregnancy, remain highly charged throughout the United States and around the globe. In the US, there were over 600,000 abortions in 2018 reported to the Centers for Disease Control (CDC); a rate of 11.3 abortions per 1,000 women aged 15-44 years (Kortsmit, Jatlaoui, Mandel, Reeves, Oduyebo, Petersen, & Whiteman, 2020). Over half of the abortions (57.7%) in 2018 occurred among women in their 20s. Interestingly, 2018 was the first year in almost a decade where there was a slight increase in the rate of abortions (1-2% across measure). Overall, the total number of reported abortions, abortion rate, and abortion ratio decreased 22% from 2009-2018 (Kortsmit, et al, 2020). For more details on the CDC data, which outlines age of parent, gestational periods, race/ethnicity, and more can be found here and below.

    Despite the seminal SCOTUS decision Roe v. Wade (1973), which protects a pregnant person’s liberty to choose to have an abortion without government prohibition, a number of states have enacted more stringent measures restricting access to abortion healthcare. In 2020, alone, 26 additional abortion restrictions were implemented across the US (Guttmacher Institute, 2020). Interestingly, states with the most limitations in access to abortion care also tend to have the most conservative (or absence) of sex education, the highest rates of unintended pregnancies and the lowest indicators of infant/child well-being (Dreweke, 2016; Medoff, 2018).

    Caesarean Section

    Cesarean section (c-sections), the surgical operation to remove an infant out of their pregnant parent’s body, has been part of human culture since ancient times (Sewel, 1998). Since 1996, c-sections have been on an almost steady rise in the United States. In 2018, approximately one-third (31.9%) of all births occurred through cesarean delivery (Martin, Hamilton, Osterman, & Driscoll, 2019). There is no question that c-sections can save lives; both of parents and children. However, there is a rising concern that many of these procedures are unnecessary, causing needless risk of complications to both mother and baby, as well as potential long-term implications (e.g. following the first c-section, there is a low probability, 10%, of later vaginal delivery; Osterman & Martin, 2014).

    One of the ongoing criticisms about the high rate of c-sections is that it is primarily financially driven in terms of payout to physicians/hospitals, rather than due to patient care. Considering that a c-section costs twice as much as a vaginal delivery, the economic boon for attending medical staff/facilities can be high. On the public side of things, almost half of US births are compensated through Medicaid (with double the payout for c-sections; Kozhimannil, Graves, Ecklund, Shah, Aggarwal, & Snowden, 2018). Added to that, one meta-analysis found that c-sections are more likely to be performed on privately insured women as compared with women using public health insurance coverage (Hoxha, Syrogiannouli, Braha, Goodman, da Costa, & Jüni, 2017). Thankfully, more efforts are being examined and implemented to reduce unnecessary births via cesarean section (Kozhimannil, et al, 2018).

    Disparities in Prenatal and Perinatal Care

    Racial and ethnic disparities in maternal care have been an issue in the United States for generations. Just as we discussed in last week’s reading, abuse against black and brown bodies has been excessive and consequential. In terms of prenatal and perinatal care, there have been ongoing discrepancies in care, resulting in inexcusable outcomes. Nearly a quarter of black women experience delays in their prenatal healthcare and they are almost twice as likely to experience pregnancy complications (Slaughter-Acey, Sneed, Parker, Keith, Lee, & Misra, 2019).

    Among industrialized nations, the US has the highest level of maternal deaths (Declercq & Zephyrin, 2020). Wang and her colleagues (2021) reported that black women are three to four times more likely to die of pregnancy-related causes compared to non-Hispanic White women. A black or indigenous person is up to 5 times more likely to die in pregnancy or up to a year after pregnancy than their white peer (Maykin & Tsai, 2020). This disparity is akin to what we saw in the 1940s (Declercq & Zephyrin, 2020).

    Importantly, when controlling for other variables, such as education, socio-economic status, accessibility, findings consistently suggest that lived experiences, in the form of racial microaggressions, influence Black women’s use of health care, particularly perinatal services (Slaughter-Acey, et al, 2019). Despite advances in healthcare, antibiotics, surgical processes, and accessibility, the data provides a stark reality of rampant, systemic inequity. As Declercq and Zephyrin (2020) note, “The US has to intentionally focus on disparities between Black and white women, in particular by naming and seeking to reduce the impacts of structural racism” (p. 12). Please see the Commonwealth Fund’s recent briefing here.

    There is a great deal of work to do to rectify the massive inequities facing this country. There are a variety of initiatives at both state-wide and the national level to address the disparities in perinatal care. To see a state by state comparison, go here. The Centers for Disease Control also has launched the “Hear Her Campaign.”

    To be clear, the disparities in maternal health are not the result of any one, single factor. It’s at the intersection of sexism and racism, that many women of color are not being heard or seen. The initiatives noted above are a very small part in rectifying this. Continued efforts to name and eliminate structural racism, as well as provide comprehensive health care for pregnant bodies, are essential.


    This week’s reading covers a wide range of concepts related to conception, pregnancy, and birth. Additionally, we highlighted some of the major disparities of perinatal care for BIPOC. There are other marginalized populations that need further examination; individuals with disabilities and gender nonconforming folks. There are also other stakeholders that were omitted from this section; partners, surrogates, midwives, and doulas. Finally, some considerations about lactation and postpartum adjustments can be explored further. Still, hopefully you got a solid introduction into the brilliance of conception, the marvel of pregnancy and birth, as well as the pressing issue of our time; building equity into the wrap-around healthcare of all people.

    Licenses & Attributions

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    This page titled 2.5: Conception, Pregnancy, and Birth is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Erika Goerling & Emerson Wolfe (OpenOregon) .

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