Chapter18 obstetrics
- 2. Obstetrics Overview • Obstetrics – Field of medicine that deals with pregnancy (prenatal), delivery of the baby, and the first six weeks after delivery (postpartum period) • Pregnancy – Nine calendar months or 10 lunar months – Forty weeks or 280 days – Divided into trimesters • Three intervals of three months each – Known as gestational period 2
- 3. Pregnancy • Fertilization or conception – Union of a sperm and a mature ovum • Takes place in outer third of the fallopian tube – Zygote • Initial name for fertilized ovum – Embryo • Name of product of conception from second through 8th week of pregnancy – Fetus • Name of product of conception from 9th week through duration of gestational period 3
- 4. Pregnancy • Two major accessory structures of pregnancy – Amniotic sac • Strong, thin-walled membranous sac that envelops and protects the growing fetus • Also known as the fetal membrane • Outer layer of sac is called the chorion • Inner layer of sac is called the amnion • Amniotic fluid within sac cushions and protects fetus during pregnancy 4
- 5. Pregnancy • Accessory structures of pregnancy – Placenta • Temporary organ of pregnancy • Provides for fetal respiration, nutrition, excretion • Functions as an endocrine gland by producing hormones necessary for normal pregnancy • Human chorionic gonadotropin (HCG), estrogen, progesterone, and human placental lactogen (HPL) 5
- 6. Pregnancy • Accessory structures of pregnancy – Maternal side of placenta • Attached to wall of uterus • Has a “beefy” red appearance – Fetal side of placenta • Has shiny, slightly grayish appearance • Contains arteries and veins that intertwine to form umbilical cord • Umbilical cord arises from center of placenta and attaches to umbilicus of fetus 6
- 7. Physiological Changes During Pregnancy • Amenorrhea – Absence of menstruation • Menstruation stops as a result of hormonal influence during pregnancy • Changes in the uterus – Small, pear-shaped organ before pregnancy – Grows to accommodate growing fetus, placenta, amniotic sac, and amniotic fluid during pregnancy 7
- 8. Physiological Changes During Pregnancy • Changes in the cervix – Chadwick’s Sign • Cervix and vagina take on a bluish-violet hue due to local venous congestion – Goodell’s Sign • Cervix softens in consistency in preparation for childbirth 8
- 9. Physiological Changes During Pregnancy • Changes in the vagina – Vagina takes on same bluish-violet hue of the cervix during pregnancy – Increase of glycogen in vaginal cells • Causes increased vaginal discharge and heavy shedding of vaginal cells – Leukorrhea • Thick, white vaginal discharge during pregnancy 9
- 10. Physiological Changes During Pregnancy • Changes in breasts – Increase in size and shape – Nipples increase in size and become more erect – Areola become larger and more darkly pigmented • Montgomery’s tubercles become more active and secrete substance that lubricates the nipples 10
- 11. Physiological Changes During Pregnancy • Changes in breasts – Colostrum is secreted • Thin, yellowish discharge from nipples throughout pregnancy • Forerunner to breast milk 11
- 12. Physiological Changes During Pregnancy • Changes in blood pressure – May experience hypotension during second and third trimesters (4th – 9th month) – Weight of pregnant uterus presses against descending aorta and inferior vena cava • When woman is lying on her back (supine) • May complain of faintness, lightheadedness, and dizziness 12
- 13. Physiological Changes During Pregnancy • Changes in urination – First trimester • Urinary frequency due to increasing size of uterus, creates pressure on bladder – Second trimester • Uterus rises up out of the pelvis and pressure on bladder is relieved – Third trimester • Frequency returns due to pressure of baby’s head on the bladder 13
- 14. Physiological Changes During Pregnancy • Changes in posture – Waddling gait • Manner of walking in which the feet are wide apart and the walk resembles that of a duck • Due to softening of pelvic joints and relaxing of pelvic ligaments • Pregnant woman’s center of gravity is offset 14
- 15. Physiological Changes During Pregnancy • Changes in the skin – Possible increased feeling of warmth and sweating • Due to increased activity of the sweat glands – Possible problems with facial blemishes • Due to increased activity of sebaceous glands – Chloasma • Hyperpigmentation (brown patches) seen on forehead, cheeks, and bridge of nose • Known as the “mask of pregnancy” 15
- 16. Physiological Changes During Pregnancy • Changes in the skin – Linea Nigra • Darkened vertical midline between the fundus and the symphysis pubis on the abdomen – Areola • Becomes darker as pregnancy progresses – Stria Gravidarum • Stretch marks on the abdomen, thighs, and breasts that occur during pregnancy 16
- 17. Physiological Changes During Pregnancy • Changes in weight – Recommended weight gain during pregnancy • Ranges from 25 to 30 pounds – Pattern of weight gain is important • 1st – 3rd month = 3 - 4 pounds total • 4th – 9th month = 1 pound per week – Critical to monitor weight gain for unexpected increases – Fluid retention – Pregnancy-induced hypertension 17
- 18. Signs and Symptoms of Pregnancy • Presumptive signs – Expectant mother • Suggests pregnancy but are not necessarily positive • Include amenorrhea, nausea and vomiting, fatigue, urinary disturbances, and breast changes – Quickening • Movement of fetus felt by the mother • Occurs around 18 – 20 weeks gestation • Described as a faint abdominal fluttering 18
- 19. Signs and Symptoms of Pregnancy • Probable signs – Observable by examiner • Much stronger indicators of pregnancy, but can be due to other pathological conditions • Should not be used as sole indicator of pregnancy • Include Goodell’s sign, Chadwick’s sign, uterine enlargement, hyperpigmentation of skin, abdominal stria, palpation of fetal outline, positive pregnancy tests 19
- 20. Signs and Symptoms of Pregnancy • Probable signs – Hegar’s sign • Softening of the lower segment of the uterus – Braxton Hicks contractions • Irregular contractions of the uterus • May occur throughout the pregnancy and are relatively painless 20
- 21. Signs and Symptoms of Pregnancy • Probable signs – Ballottement • Technique of using the examiner’s finger to tap against the uterus, through the vagina, to cause the fetus to “bounce” within the amniotic fluid and feeling it rebound quickly 21
- 22. Signs and Symptoms of Pregnancy • Positive signs – Fetal Heartbeat • Detected by ultrasound at approximately 10 weeks gestation • Detected by fetoscope at 18 to 20 weeks gestation • Rate can vary from 120 to 180 beats per minute 22
- 23. Signs and Symptoms of Pregnancy • Positive signs – Identification of embryo or fetus by ultrasound • Can be detected as early as 5 to 6 weeks with 100 percent reliability • Provides earliest positive confirmation of a pregnancy – Fetal movements felt by examiner • Palpable by physician/examiner by the second trimester of pregnancy 23
- 24. Calculation of Date of Birth • Birth date for the baby – Expected Date of Confinement (EDC) – Expected Date of Delivery (EDD) – Expected Date of Birth (EDB) • Nagele’s rule for calculation of date – Subtract three months from beginning of last menstrual period (LMP) – Add seven days to date = expected date of delivery 24
- 25. Discomforts of Pregnancy • Temporary discomforts of pregnancy – Backache • Common during second and third trimester – Edema • Swelling of lower extremities not uncommon – Fatigue • Usually occurs during first trimester 25
- 26. Discomforts of Pregnancy • Temporary discomforts of pregnancy – Heartburn • Mainly during last few weeks of pregnancy – Hemorrhoids • Develop as result of increasing pressure on area – Nausea • Usually occurs during first trimester – Varicose veins • Occur as result of blood pooling in the legs 26
- 28. Abortion • Pronounced – (ah-BOR-shun) • Defined – Termination of a pregnancy before the fetus has reached a viable age, that is, an age at which the fetus could live outside of the uterine environment 28
- 29. Abruptio Placenta • Pronounced – (ah-BRUP-she-oh pla-SEN-tah) • Defined – Premature separation of a normally implanted placenta from the uterine wall • After the pregnancy has passed 20 weeks gestation or during labor 29
- 30. Ectopic Pregnancy • Pronounced – (ek-TOP-ic PREG-nan-see) • Defined – Abnormal implantation of a fertilized ovum outside of the uterine cavity – Also called a tubal pregnancy • Approximately 90 percent of all ectopic pregnancies occur in the fallopian tubes 30
- 31. Gestational Diabetes • Pronounced – (jess-TAY-shun-al diy-ah-BEE-teez) • Defined – Disorder in which women who are not diabetic before pregnancy develop diabetes during the pregnancy • Develop an inability to metabolize carbohydrates (glucose intolerance), with resultant hyperglycemia 31
- 32. Gestational Diabetes • Risk factors – Obesity – Maternal age over 30 years – History of birthing large babies • Usually over 10 pounds – Family history of diabetes – Previous, unexplained stillborn birth – Previous birth with congenital anomalies (defects) 32
- 33. HELLP Syndrome • Pronounced – HELLP SIN-drom • Defined – Serious obstetrical complication that occurs in approximately 10 percent of pregnant women with pre-eclampsia or eclampsia • HELLP stands for Hemolytic anemia, Elevated Liver enzymes, and Low Platelet count 33
- 34. HELLP Syndrome • Early diagnosis is critical – Any woman who presents with malaise or a viral-type illness in third trimester of pregnancy should be evaluated for possibility of HELLP Syndrome • Laboratory diagnosis necessary to confirm HELLP syndrome – Complete blood cell count – Liver function tests 34
- 35. Hydatidiform Mole • Pronounced – (high-dah-TID-ih-form mohl) • Defined – Abnormal condition that begins as a pregnancy and deviates from normal development very early • Diseased ovum deteriorates (not producing a fetus) • Chorionic villi of placenta changes to a mass of cysts resembling a bunch of grapes 35
- 36. Hydatidiform Mole • Hydatidiform mole – Molar pregnancy – Hydatid mole – Growth of this mass progresses much more rapidly than uterine growth with a normal pregnancy 36
- 37. Hyperemesis Gravidarum • Pronounced – (high-per-EM-eh-sis grav-ih-DAR-um) • Defined – Abnormal condition of pregnancy characterized by severe vomiting that results in maternal dehydration and weight loss 37
- 38. Incompetent Cervix • Pronounced – (in-COMP-eh-tent SER-viks) • Defined – Condition in which cervical os dilates before the fetus reaches term, without labor or uterine contractions • Usually occurs during second trimester of pregnancy • Results in spontaneous abortion of fetus 38
- 39. Placenta Previa • Pronounced – (plah-SEN-tah PRE-vee-ah) • Defined – Condition of pregnancy in which the placenta is implanted in the lower part of the uterus • Precedes the fetus during the birthing process 39
- 40. Pregnancy-Induced Hypertension (PID) • Pronounced – (PREG-nan-see induced high-per-TEN- shun) • Defined – Development of hypertension during pregnancy, in women who had normal blood pressure readings prior to pregnancy 40
- 41. Pregnancy-Induced Hypertension (PID) • Three categories of PID – Gestational hypertension • Develops after 20 weeks gestation with no signs of edema or proteinuria – Pre-eclampsia • Develops after 20 weeks gestation with proteinuria or edema – Eclampsia • Most severe form of hypertension during pregnancy • Evidenced by presence of seizures 41
- 42. Rh Incompatibility • Pronounced – (Rh Incompatibility) • Defined – Incompatibility between and Rh negative mother’s blood with her Rh positive baby’s blood • Causes mother’s body to develop antibodies that will destroy the Rh positive blood 42
- 43. SIGNS AND SYMPTOMS OF LABOR Obstetrics
- 44. Signs and Symptoms of Labor • Bloody show – Vaginal discharge that is a mixture of thick mucus and pink or dark brown blood • Occurs as a result of the softening, dilation, and thinning (effacement) of the cervix in preparation for childbirth 44
- 45. Signs and Symptoms of Labor • Braxton Hicks contractions – Mild, irregular contractions that occur throughout pregnancy • Increased vaginal discharge – Clear, nonirritating vaginal secretions – Occurs as result of congestion of vaginal mucosa 45
- 46. Signs and Symptoms of Labor • Lightening – Settling of the fetal head into the pelvis • Occurs a few weeks prior to the onset of labor • Rupture of the amniotic sac – Rupture of fetal membranes, releasing amniotic fluid inside • May result in a sudden gush of amniotic fluid • Women may say their “water broke” 46
- 47. Signs and Symptoms of Labor • Sudden burst of energy – Occurs in some women shortly before onset of labor – May have energy to do major housecleaning duties 47
- 48. False Labor versus True Labor Contractions (False) Contractions (True) Irregular Regular Not too frequent More frequent Shorter duration Longer duration Not too intense More intense 48
- 49. False Labor versus True Labor Discomfort (False) Discomfort (True) Felt in abdomen Felt in lower back Felt in groin area Radiates to lower abdomen --- Feels like menstrual cramps 49
- 50. False Labor versus True Labor Walking (False) Walking (True) May relieve or decrease May strengthen contractions contractions 50
- 51. False Labor versus True Labor Effacement/Dilatation Effacement/Dilatation (False) (True) Dilatation and Cervix progressively effacement of cervix effaces (thins) and does not change dilates (enlarges) 51
- 52. DIAGNOSTIC TECHNIQUES, TREATMENTS AND PROCEDURES Obstetrics
- 53. Diagnostic Techniques, Treatments, and Procedures • AFP screening – Serum screening test for birth defects such as spina bifida, Down syndrome, and Trisomy 18 • Test is offered to pregnant women between 15 and 21 weeks gestation 53
- 54. Diagnostic Techniques, Treatments, and Procedures • Amniocentesis – Surgical puncture of the amniotic sac for the purpose of removing amniotic fluid • Cesarean section – Surgical procedure in which the abdomen and uterus are incised and a baby is delivered transabdominally 54
- 55. Diagnostic Techniques, Treatments, and Procedures • Contraction stress test – Stress test used to evaluate ability of fetus to tolerate stress of labor and delivery • Also known as oxytocin challenge test • Fetal monitoring – Use of an electronic device to monitor fetal heart rate and maternal uterine contractions 55
- 56. Diagnostic Techniques, Treatments, and Procedures • Nipple stimulation test – Noninvasive technique that produces same results as contraction stress test • Pregnant woman stimulates the nipples of her breasts by rubbing them between her fingers • Causes natural release of oxytocin that causes contractions of uterus 56
- 57. Diagnostic Techniques, Treatments, and Procedures • Obstetrical ultrasound – Noninvasive procedure that uses high- frequency sound waves to examine internal structures and contents of the uterus – Ultrasonography 57
- 58. Diagnostic Techniques, Treatments, and Procedures • Pelvic ultrasound – Noninvasive procedure that uses high- frequency sound waves to examine the abdomen and pelvis • Pelvimetry – Process of measuring the female pelvis, manually or by x-ray to determine its adequacy for childbearing 58
- 59. Diagnostic Techniques and Procedures • Pregnancy testing – Tests performed on maternal urine and/or blood to determine presence of hormone HCG (human chorionic gonadotropin) • HCG is detected shortly after first missed menstrual period 59