king, human sexuality today, 5/e © 2005 by prentice hall 1 chapter 7 pregnancy and childbirth for...

King, Human Sexuality Today, 5/e © 2005 by Prentice Hall1

Chapter 7Pregnancy and Childbirth

For use with text,

Human Sexuality Today,

5th edition.

Bruce M. King

Slides by Callista Lee


Conception and implantation (1)

Within the ovary, a primary follicle matures into a Graafian follicle, which breaks open to release an ovum at ovulation.

Ovum can be fertilized for first 24 hours during its 3-7 day journey through the Fallopian tube to the uterus.

200-300 million sperm are released at ejaculation, most dying or becoming “lost.”



Most sperm live only 3 days inside the woman’s reproductive tract; some for 5 days.

While moving toward the egg (ovum), sperm undergo “capacitation.”

The 50 sperm reaching the egg release an enzyme that softens the egg’s outer layers.

The egg pulls one sperm to its surface, the “zona pellucida” where sperm then secretes an enzyme allowing it to penetrate and enter.



Conception (fertilization) has taken place; a chemical reaction prevents other sperm from breaching the egg’s surface.

Within 24-30 hours, nuclei of sperm and egg fuse to form the one-celled “zygote,” which contains a complete genetic code for a new human being.

Cell division begins– Morula stage (small collection of cells)– Blastocyst stage (over 100 cells; fluid center)



Blastocyst arrives in the uterus which is receptive to implantation for only 4-5 days.

8-11 days after ovulation the blastocyst attaches itself to the endometrium; then the conceptus is referred to as an embryo.

Embryo’s outer layer = trophoblast, grows rapidly, forming 4 protective layers (membranes) around the embryo.



Trophoblast membranes –– One produces blood cells– A 2nd develops into the umbilical cord– A 3rd, the amnion; protective fluid-filled sac– A 4th, the chorion, develops into the

placenta, which will serve as an interface with the mother


Problems with implantation

Three-fourths of conceptions fail to implant or are spontaneously aborted (miscarriage) within first 6 weeks for reasons generally unknown.

Ectopic pregnancy – implantation somewhere other than within the uterus.– Tubal pregnancies usually abort but may

continue growing, putting the mother’s life at risk

– Some causes: PID, aging mother, smoking, douching, anatomical malformations


Pregnancy

Pregnancy lasts an average of 266 days (38 weeks); approximately 9 months – divided into 3 trimesters.


First trimester – The parents

HCG (human chorionic gonadotropin) hormone from the placenta appearing in the mother’s blood/urine will confirm a pregnancy.

“Morning sickness” – 4 – 6 weeks after conception in 70-90% of pregnant women; disappears by week 20

Couvade syndrome – sympathy pains experienced by the father (psychosomatic)


First trimester – The embryo/fetus

Ectoderm – nervous system, skin, teeth– Neural tube is developing by the 3rd week

Mesoderm – muscles, skeleton, blood vessels Endoderm – internal organs

– Umbilical cord, heart, digestive system begin developing by end of 4th week

6 weeks – embryonic “tail” and a “gilled” look 8 weeks – now called a fetus, 1-1/8 inches long


Third month

By the end of the 3rd month, the fetus is about 3 inches long, weighs about 1 ounce. Uterus begins to enlarge.


Second trimester - Mother

“Quickening” (fetal movements) experienced by the mother at 4-5 months; most mothers begin viewing the new life as a “person” by this time.

Stretch marks, breast swelling and colostrum leakage, hemorrhoids, and water retention causing edema in feet, ankles and hands.

Renewed appetite with cessation of morning sickness.


Second trimester - Fetus

Mouth makes sucking motions Detectable heartbeat in 5th month Periods of sleep and wakefulness If born at this time, a 1-in-10,000 chance of

survival At 6 months, eyes can open, thumb sucking Final length about 1 foot; weight 1 pound


Fifth month

Fetus is bright red in color. Its increased size pushes the dome of the uterus to a level of the umbilicus. Internal organs are maturing quickly but lungs cannot cope with conditions outside the uterus.


Third trimester – The mother

Walking, sitting, rising have become difficult. Enlarging uterus puts pressure on the bladder

and digestive organs. Frequent urination, indigestion, heartburn, gas,

constipation, leg cramps, back pain, low energy level are all common.


Seventh month

Fetal weight doubles from 6th month; 3 inches longer. Skin is red and wrinkled. At 7 months a premature baby has a fair chance of survival if it receives skilled, specialized care.


Third trimester – The fetus

Fatty tissues begin to develop under the skin in the 7th month; weight increases dramatically in the 8th month to about 4 pounds; 16-17 inches long.

In 9th month, weight increases to an average of 7-7 ½ pounds; 20 inches long.

Fetus is covered in light hair (lanugo) and a waxy bluish substance (vernix caseosa).


Ninth month

At birth, a full-term baby weighs about 7 ½ pounds; 20 inches long. Born with vernix but the lanugo has largely disappeared. Fingernails may protrude beyond the fingertips.


Sexual activity during pregnancy

90% of couples were still having sexual intercourse in the 5th month of pregnancy.

Changing hormones, physical discomforts and concerns about attractiveness, concerns about harming the fetus decrease women’s interest in sex. Men do not report the woman’s attractiveness as a factor.

In most cases sex during the first 8 months is perfectly safe.


Complications of pregnancy

97% of all births result in healthy infants. Teratogens – substances that can cross the

placental barrier and cause harm to the fetus. Critical period – For each part of the

developing fetus, a period of time during which it is most susceptible to damage.

Most body parts are maximally susceptible during the first 8 weeks of development.


Critical periodsin prenatal development

Darker shading represents highly sensitive periods


Complications - Diseases

Rubella (German measles) – blindness, deafness, intellectual impairment

STDs – HIV, syphilis, gonorrhea, chlamydia, HPV, HSV (see Chapter 5)

Toxemia of pregnancy – Preeclampsia – 3-5% of women; high blood

pressure, excessive water retention, weight gain– Eclampsia – convulsions and coma of the mother


Complications – Toxic substances

Smoking – low-birth-weight, miscarriage, ectopic pregnancy, preterm birth, sudden infant death syndrome (SIDS), anti-social behaviors.

Fetal Alcohol Syndrome and Fetal Alcohol Effect – in moderate and heavy drinkers; physical deformities, mental retardation, anti-social behaviors, hyperactivity, learning disabilities.

Alcohol has its maximum impact in week 3.


Complications – Drugs and medications

Cocaine – low-birth-weight, preterm births, sensory-motor and behavioral disorders.

Opiate dependency – fever, tremors, convulsions, difficulty breathing.

Marijuana – brain and behavioral disorders. Caffeine – reduced birth-weight Antibiotics, tranquilizers, antihistamines,

aspirin, mega-doses of some vitamins


Additional complications

Rh incompatibility – mismatch of fetal and maternal blood types leads to maternal antibodies that will cross the placenta and attack the fetal blood supply.

– Treatment with Rhogam prevents formation of these antibodies.

Miscarriage (spontaneous abortion) – of conceptions that survive the first 6 weeks only 10% survive to full-term.

– Genetic, anatomic & hormonal problems, infections, smoking, cocaine use, maternal auto-immune responses.


Complications – Diagnosis

Chorionic villus sampling – tube through the cervix suctions out cells from the chorion, up to 12th week; risk of miscarriage 1-2%.

Celocentesis – needle between placenta and amniotic sac retrieves cells (safer than CVS).

Amniocentesis – needle through abdomen retrieves sample of amniotic fluid; between 14-18th weeks; 1% risk of miscarriage.

Ultrasound – sound waves detect skeletal malformations but not genetic defects.


Treatment prior to birth

Fetal surgery – operations performed while the fetus is still inside the uterus of the mother may repair conditions that would have led to death shortly after birth.

In utero gene therapy – in the near future, healthy genes will be injected into organs suffering from genetic diseases.


Prenatal nutrition and exercise

One of the best ways to increase chances of having a healthy baby is to eat properly.

Obtain education healthy diet and appropriate supplemental vitamins.

Normal weight gain for normal weight women is 25-35 lbs; 15 lbs if overweight; 28-40 lbs if underweight.

Regular exercisers have timely deliveries and reduced risk of preterm births.


Prepared Childbirth

Prenatal medical examinations Overcoming the fear-tension-pain cycle

through education and relaxation training Lamaze – anxiety reduction, muscle relaxation,

muscle stretching, breathing, massage Bradley – Lamaze-like, no medication,

increased role of the husband/father Leboyer – gentle, gradual introduction of baby

to new environment


Childbirth – Place and providers

Hospital birthing rooms – less hospital-like Birthing centers – homelike atmosphere,

staffed by nurse mid-wives or physicians– Relatively new in the U.S. but popular in Europe

Nurse-midwives – growing trend, high quality care at less expense, outcomes just as good as births attended by physicians.


Anesthetics or “natural” childbirth?

General anesthesia – mother is unable to participate and baby must be pulled from her. The infant is also affected by the anesthesia.

Epidural (spinal anesthetic) – deadens sensations from the waist down; extends labor and risk of low blood pressure in the mother.

Women who have prepared childbirth and are assisted by nurse-midwives use less pain medication and need fewer cesarean sections.


Childbirth

Lightening – the baby “drops” into position Braxton-Hicks contraction (false labor) –

practice exercises for the uterus prior to labor. True labor – regular contractions, 10 minutes

apart; dilation of the cervix, effacement of the cervix.

Go to the hospital/birthing center when contractions are 20 minutes apart.


Stages of childbirth


Childbirth – First stage of labor

Start-up stage – 6-13 hours– Early contractions are brief (15-20 seconds) and

go from 10 or 20 minutes apart to 1-2 minutes apart with longer duration (45-60 seconds).

– Amniotic sac breaks (water breaks) either prior to beginning of labor or during this stage.

– Transition phase – 40 minutes or less; cervix almost fully dilated, contractions are severe.


Childbirth – Second stage of labor

Begins when cervix is fully dilated and fetus begins moving through the birth canal.– 40% will be given an episiotomy to widen the

birth canal; useful if baby is in distress– Mother feels a desire to push or “bear down”– Lasts 30-80 minutes– Crowning of the fetus’ head– Physician or nurse-midwife reaches in to check

umbilical cord placement– Baby is delivered, umbilical cord is cut


Childbirth – Third stage of labor

Placenta detaches from uterus and leaves the body (afterbirth). 10-12 minutes.

The physician or nurse-midwife examines the afterbirth to be certain that all of it has come out – small remnants in the uterus can cause infection and bleeding.


Problems with childbirth

Placenta previa – placenta blocks cervix– May prevent a vaginal delivery

Preterm infants – 12% of U.S. births– Respiratory distress syndrome is greatest problem– Today babies weighing at least 2.5 lbs have 80% survival– Babies 3 lbs or less – mental and psychomotor disabilities

Cesarean section – recovery takes longer but many women prefer it to longer vaginal delivery

Breech births – 2-4% of births– If the fetus cannot be turned a cesarean section may be

performed.


Afterwards – Breast-feeding

Milk production (lactation) begins about 3 days after birth. Prolactin stimulates milk production, Oxytocin causes the breasts to eject milk.

Before milk production, breasts give out colostrum – high in protein and immunities.

Mother’s milk is high in infection-fighting proteins; babies have higher IQs as adults; mothers quit bleeding earlier and reduce risk of breast cancer.


Afterwards – Postpartum

The 3 months following birth = postpartum Postpartum blues (baby blues) – common

letdown after birth due to hormonal changes, exhaustion and the stress of adapting to a new child in the family.– Depressed mood, confusion, anxiety, crying.– Symptoms are generally mild and not long-

lasting.– Preparative education and supportive family

members can be very helpful.


Postpartum depression (PPD)

In 10% of mothers, PPD severe enough to require professional treatment– Deep depression, anxiety, guilt, fatigue, and

often obsessive-compulsiveness Postpartum psychosis – 1 in 1,000 mothers

– Severely disordered moods, hallucinations, delusion

– Biological and psychiatric origins– Professional treatment needed and childcare for

all children in the family


Sexual intercourse after birth

Heal from a vaginal birth first; 4-6 weeks; most resume intercourse at about 7 weeks.

Women who’ve had episiotomies or c-sections may require extra healing time.

Vaginal bleeding continues for 2-6 weeks. Loss of estrogen results in vaginal dryness. Pregnancy sooner than 23 months may result

in premature and underweight baby.


Infertility and impaired fecundity

Infertility – inability of a couple to conceive Fecundity – ability of a couple to conceive

within a certain period of time (usually a year) 40% of infertility problems are due to the man,

40% due to the woman, 20% both partners.


Infertility in men

Low sperm count or abnormal sperm– Hormonal problems, recreational drugs and

medicines, radiation, infections, heat, varicosity of veins in the spermatic cord, pollutants

Artificial insemination– His sperm is collected via masturbation and inserted

into the woman’s uterus immediately after ovulation.

Intracytoplasmic sperm injection– Injection of a single sperm directly into an egg/ovum


Infertility in women

Fallopian tube blockage (25-35% of cases) – Growths, PID, endometriosis are common causes

Failure to ovulate regularly (most cases)– Hormonal irregularities can be treated with fertility

drugs– Chances of multiple births are increased from the

normal rate of 1-2% to 20%– Concerns about ovarian cancer risk


Assisted reproductive technology

In vitro fertilization (IVF) – eggs and sperm combined in a petri dish; several fertilized eggs are placed into the uterus; 20-50% success

Gamete intrafallopian transfer (GIFT) – eggs and sperm placed separately into the fallopian tube; 27-50% success

Zygote intrafallopian transfer (ZIFT) – fertilization in a petri dish; conceptus placed into the fallopian tube; slightly less effective than GIFT.


Other options for infertile couples

Surrogate motherhood – couple creates a zygote via IVF which is implanted in the uterus of another woman.– Legal and emotional issues must be addressed.

Older and even postmenopausal women have received hormonal treatments along with IVF to allow for childbearing later in life. – Older eggs more prone to certain birth defects– Mother more prone to diabetes, high BP, c-section

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