Obstetrics and Gynecology Notes PDF

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Obstetrics and Gynaecology SyllabusPart I. Physiology of Pregnancy, Labour and Delivery Anatomy of the female reproductive system Anatomy of the female pelvis - structure, planes, distances Fertilization. Implantation. Fetal development The placenta, umbilical cord, the membranes and the amniotic fl...

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Obstetrics and Gynaecology Syllabus Part I. Physiology of Pregnancy, Labour and Delivery 1. Anatomy of the female reproductive system 2. Anatomy of the female pelvis - structure, planes, distances 3. Fertilization. Implantation. Fetal development 4. The placenta, umbilical cord, the membranes and the amniotic fluid 5. Obstetric history. Gestational age assessment and determination of the estimated day of delivery 6. Obstetric physical examination - palpation (Leopold methods), abdominal measurements, pelvimetry, auscultation of the fetal tones. Position of the fetus in utero - habitus, situs, position, presentation of the fetus. 7. Diagnosis of early and advanced pregnancy 8. Maternal physiological adaptations during pregnancy. Hygiene and diet during pregnancy 9. Methods for the assessment of fetal well being during pregnancy and in labor ultrasound examination, CTG (non-stress test and contraction stress-test), amniocentesis, fetal blood sampling from the presenting part with microanalysis, amnioscopy 10. Congenital fetal anomalies - prenatal screening and diagnosis 11. Theories for the onset of labor. Stages of labor 12. Biomechanics of labor Management of normal labor 13. Pain relief during labor 14. The normal puerperium. Care for the parturient 15. Lactation - mechanisms, stimulation, suppression. Care for the breasts during pregnancy and lactation 16. Physiology of the newborn. Immediate care for the newborn

Part II. Pathology of pregnancy, labor and delivery 17. Trophoblastic disease 18. Spontaneous abortions (miscarages) - types, etiology and management

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19. Preterm delivery. The preterm neonate 20. Post term pregnancy. The post term neonate 21. Multiple pregnancy 22. Hyperemesis gravidarum. Sialorrhoea 23. Hypertensive disorders during pregnancy. Preeclampsia, HELLP syndrome, eclampsia 24. Diabetes and pregnancy 25. Infectious diseases and pregnancy 26. Ectopic pregnancy 27. Bleeding in the second half of pregnancy - placenta previa and placental abruptionDysfunctional labor (functional dystocia). Medicines that influence uterine contractility

28. Contracted pelvis - types, diagnosis. Mechanical dystocia - management 29. Unstable fetal lie (transverse, oblique). Atypical and pathological cephalic presentations 30. Presentation and prolapse of the umbilical cord and of small fetal parts. Abnormalities of the amniotic fluid and the membranes 31. Bleeding in the third stage of labor and in the early postpartum period 32. Birth canal injuries and fetal trauma - types, diagnosis, management, prevention 33. The pathologic puerperium, puerperal infections. Mastitis 34. Breech presentations. Mechanisms of labor. Manual assistance 35. Vaginal operative delivery - extraction with forceps, ventouse (instruments, indications, technique) 36. Cesarean section - indication, types, complications 37. Manual separation and extraction of the placenta, manual and instrumental exploration of the uterine cavity, uterine packing - indications, technique 38. Shock in obstetrics. Amniotic fluid embolism. Coagulopathies in obstetrics

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39. Asphyxia of the newborn - causes, diagnosis, management. Primary resuscitation of the newborn

Part III. Gynecology 41. Gynecological history. Clinical gynecological examination. Normal findings at pelvic exam 42. Special diagnostic methods in gynecology - ultrasound, cytology, colposcopy, HSG (hysterosalpingography), D&C (dilation and curettage), laproscopy, hysteroscopy 43. Cardinal symptoms in gynecology 44. Neuroendocrine regulation of the menstrual cycle 45. Menstrual disturbances. Functional (dysfunctional) uterine bleeding 46. PCOS (polycystic ovarian syndrome) 47. The climacterium 48. Vulvovaginitis - types, characteristic features, treatment. Sexual transmitted diseases. HIV/AIDS 49. Pelvic inflammatory disease 50. Endometriosis 51. Cervical cancer 52. Uterine fibrosis. Uterine sarcoma 53. Endometrial cancer 54. Ovarian tumors - benign 55. Ovarian tumors - malignant. Ovarian cancer 56. Prevention of the premalignant and malignant disorders of the female reproductive system 57. Gynecology of childhood and adolescence 58. Congenital anomalies of the female reproductive system 59. Pelvic floor relaxation. Urinary incontinence 60. Sterility. Infertility 61. Contraception

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1. Anatomy of the female reproductive system The female reproductive system consists of the following:  The vulva (external genitalia)  The vaginia  The cervix  The Uterus  The fallopian (uterine) tubes  The ovaries The vulva

Important anatomical parts of the vulva are:

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Mons pubis - a subcutaneous fat bad anterior to the pubic symphysis

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Labia majora - two hairy external skin folds that extend from the mons pubis to the posterior commissure

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Labia minora - two hairless skin folds that lie deep within the labia majora. Fuse anteriorly to form the clitoral hood, and posteriorly to form the fourchette

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Vestibule - the area enclosed by the labia minora, contains vaginal and urethral openings

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Bartholin’s glands - secrete mucus from small ducts during sexual arousal, are on either side of the vaginal orifice

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Clitoris - under the clitoral hood at the apex of the vulva

Vasculation is via internal and external pudendal arteries, innervation from ilioinguinal nerve, genital branch of the genitofemoral nerve, pudendal nerve and posterior cutaneous nerve of the thigh

The vagina The vagina is a distensible muscular tube which extends posterosuperiorly from the external vaginal orifice to the cervix. Its roles include receiving the penis and ejaculate, providing a channel for the delivery of a newborn from the uterus, and serves as a canal to allow menstrual fluid to leave the body. The vagina has some important anatomical relations, anterior to it sits the bladder and the urethra, posteriorly is the rectouterine pouch, rectum and anal canal, while laterally is the ureters and levator ani muscle. The vagina has anterior and posterior walls which are usually collapsed and are therefore in contact with one another. At the upper part, the vagina surrounds the cervix creating two fornices, and anterior and posterior one (the posterior is deeper). The posterior fornix acts as a resevoir for seman after intravaginal ejaculation, allowing for permeation through the cervical canal. Histologically the vagina has four layers, lets work internal to external:  Stratified squamous epithelium  Elastic lamina propria  Fibromuscular layer  Adventitia Blood is from the internal iliac artery, innervation is from the uterovaginal nerve plexus (autonomic).

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Cervix The the with the vagina, acting as a gateway between them.

cervix is the lowest portion of uterus, connecting the uterus

The cervix has two parts, the ectocervix and the endocervical canal, there are also two openings, the internal and external os. The ectocervix is projected into the vagina and is lined by stratified squamous non-keratinized epithelium, meanwhile the endocervical canal is the more proximal part and lined by simple columnar epithelium. The cervix allows the passage of sperm into the uterine cavity, as well as maintaining sterility of the upper female reproductive tract, all proximal structures are sterile. Blood is from the uterine artery. Uterus The uterus is a muscular organ capable of expansion to accommodate the growing fetus, it connects distally to the vagina (via the cervix) and laterally to the uterine tubes. The uterus has three parts:  Fundus (where the uterine tubes enter)  Body (where the blastocyst should implant)  Cervix (see above) The uterus can vary slightly in relation to its position regarding the vagina. It may be:  Anteverted (anteriorly pushed on top of the bladder)  Anteverted and Anteflexed (additional flexion of the most proximal part of the uterus)  Retroverted (posteriorly pushed back towards the rectum)  Retroverted and Retroflexed (additional posterior flexion towards the rectum)

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Histologically, the uterus has three layers of tissues, the endometrium (with a deep and superficial layer), myometrium and peritoneum. Five ligaments help secure the uterus, these are:  The broad ligament (double layer of peritoneum attaching the uterus to the pelvis)  The round ligament (sectures the uterine horns to the labia majora)  The ovarian ligament (joints ovaries to the uterus)  The cardinal ligament (at base of broad ligament, attaches cervix to the lateral pelvic walls) The uterosacral ligament (from cervix to sacrum) Blood comes from the uterine artery. 

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The fallopian (uterine) tubes Muscular, J-shaped tubes, the fallopian tubes lie in the upper border of the broad ligament, extending laterally from the horns of the uterus and then opening into the abdominal cavity, near the ovaries. Their main function is to transfer the ovum from the ovary to the uterus, to facilitate this, the tube has an inner ciliated columnar epithelial mucosa that waft the ovum towards the uterus, along with a smooth muscle layer that contracts to propel the ova towards the sperm. The fallopian tube has four parts:  Fimbriae - ciliated projections that capture the ovum from the surface of the ovary  Infundibulum - funnel-shaped opening near to the ovary with the fimbriae attached  Ampulla - the widest section of the tube, fertilization usually occurs here  Isthmus - narrowest section of the tube, where the ampulla attached to the uterus

Blood from the uterine and ovarian arteries, innervation is sympathetic and parasympathetic from the ovarian and uterine plexuses.

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The ovaries These are the female gonads. They develop from the mesonephric ridges and descend through the abdomen. They are paired, oval and attached to the posterior surface of the broad ligament. The main function of the ovaries is to produce the female gamete, oocytes, and produce oestrogen and progesterone in response to LH and FSH. Ovaries have three parts:  Surface - formed by simple cuboidal epithelium, known as germinal epithelium  Cortex - the outer part, comprised of connective tissue stroma, it supports follicles which each contain and oocyte surrounded by follicular cells  Medulla - the inner part, with a neurovascular network which enters the hilum of the ovary from the mesovarium.

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The ovaries are held by the suspensory ligament of ovary, which is anchored to the mesovarium and pelvic wall. And the ligament of ovary, which attaches the ovary to the fundus of the uterus. All of these sit on the backdrop of the broad ligament. Blood is from the ovarian arteries with autonomic innervation from the ovarian and uterine plexuses.

2. Anatomy of the female pelvis - structure, planes, distances The bony pelvis is comprised of the pubic symphysis anteriorly, laterally the two hip bones (illium, ischium and pubis) and posteriorly the sacrum. These form the pelvic girdle. There are two joints within this, the paired sacroiliac joint, the sacrococcygeal joint and the pubic symphysis. Important ligaments that hold this together are:  Interpubic ligament - supports the pubic symphysis  Right/Left Anterior Sacroiliac ligament - supports the sacroiliac joint anteriorly  Right/Left Posterior Sacroiliac ligament - supports sacroiliac joint posteriorly o Interosseous lg o Short lg o Deep lg  Right/Left Posterior Sacrococcygeal ligament o Superficial lg o Deep lg  Right/Left Anterior Sacrococcygeal ligament  Right/Left Sacrospinous ligament  Right/Left Posterior Sacrotuberous ligament Review the images below that highlight these building blocks.

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The above image shows a ‘greater’ pelvis and a ‘lesser’ pelvis, separated by the linea

terminalis. The greater pelvis is the space bordered by the iliac fossa, iliac crests, lumbar vertebrae, and anteriorly the anterior abdominal wall. It provides support to the abdominal organs as well as the pregnant uterus at term. The ‘lesser’ (sometimes known as true) pelvis on the other hand contains the pelvic viscera (the uterus, vagina, bladder, fallopian tubes, ovaries, distal rectum and anus). It is formed by the sacrum and coccyx posteriorly, and the ischium and pubis laterally and anteriorly. The lesser pelvis has three separate parts. These are the Pelvic inlet (brim) the cavity (midpelvis) and the pelvic outlet. We consider each below:  The Pelvic Inlet o The boundaries are  The sacral prominence  Iliopectineal lines  Iliopectineal eminences  Upper border of the superior pubic rami  Upper border of the symphysis pubis  When the fetal head enters the pelvic inlet it is described as being ‘engaged’  The pelvic inlet has four diameters which we consider in detail below.  The pelvic cavity (the midpelvis)  Bounded by the inlet above and the obstetric outlet below  Anteroposterior diameter is between 2nd-3rd Sacral vertebra to the midpoint of posterior surface of symphysis pubis = 12cm. The transverse and oblique diameters cannot be easily measured, but are approximated at 12cm.  The Pelvic outlet  Has two parts, the Obstetric outlet and the Anatomical outlet  Obstetric outlet is a diamond shaped space between the tip of the sacrum, the two ischial spines and the lower border of the symphysis pubis. Its anteroposterior diameter (tip of sacrum to lower border of symphysis pubis) is about 11cm, while its transverse diameter between the two ischial spines is about 10.5cm.  The Anatomical outlet is between the tip of the coccyx, the two ischial tuberosities and the lower border of symphysis pubis. The anteroposterior diameter is 13cm here, and the intertuberous diameter is 11cm.

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Diameters of the Pelvic inlet There are four diameters, these are:  Anteroposterior diameter  Two Oblique diameters  Transverse diameter The anteroposterior diameter has itself three measurements  Anatomical/True conjugate - Mid point of sacral promontory to the inner margin of the upper border of symphysis pubis - about 11cm  Obstetric conjugate - Mid point of sacral promontory to the midline of inner surface of symphysis pubis - about 10cm  Diagonal conjugate - Midpoint of sacral promontory to the lower border of symphysis pubis - about 12 cm The anteroposterior diameter cannot be measured in direct vaginal examination, however we can estimate it based on measuring the distance from the lower margin of the symphysis to the sacral prominence The two oblique measurements are the diagonal measurements across the true pelvis, measuring from one sacroiliac joint to the opposite iliopectineal eminence on the pubic bone. This usually measures about 12cm. The transverse diameter has two measurements:  Interspinous distance - between the two spinous processes of the iliac bone = 10cm  Transverse diameter - the widest point of the true pelvis, just on the iliopectineal line = 13.5 cm

Types of pelvis There are generally four types of pelvic shape that are accepted based on the CaldwellMoloy model. These are:  Gynecoid (Round) - 50% of women o This is generally the best for giving birth - The inlet is a slightly transverse oval, with a wide sacrum and not too significant a concave shape or inclination.  Anthropoid (Oval-long) - 25% of women o All anteroposterior diameters are long, while the transverse diameters are short. The sacrum is long and the subpubic angle is narrowed  Android (wedge) - 20% o The inlet is triangular, with a narrow apex but wider posterior. Side walls converge with projecting ischial spines which can cause arrest of labor  Platypelloid pelvis (oval) - 5%

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o

All anteroposterior diameters are short, while the transverse diameters are long.

3. Fertilization. Implantation. Fetal development

Fertilization Fertilization occurs when a spermatozoa and oocyte come together, most commonly in the ampulla of the fallopian tube. In order to understand fertilization we need to understand sperm cells and oocytes before we look into the mechanics of the process. The sperm cell consists of a tail for propulsion, a middle section packed with mitochondria which provide energy for the tail, and a head, which includes haploid genetic information and an acrosome which has digestive enzymes to allow the sperm to merge with the oocyte. The egg cell (oocyte) is much larger than the sperm cell (x10,000). The egg cell consists of three structures around the edge, the Corona radiata, the Zona pellucida (glycoprotein layer)

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and a plasma membrane, while inside sits mitochondria, ooplasm, and the haploid genetic

information. Human fertilization is the union of a human egg and sperm, usually occurring in the ampulla of the fallopian tube. Fertilization can be seen as a series of events as explained below:  Sperm ejaculated during copulation and travels through the cervix and the uterus into the fallopian tube  The sperm then reaches the egg and penetrates the zona pellucida to get to the oocyte. It does this by utilizing the digestive enzymes that are held in the acrosome of the head of the spermatozoa  Consistent propulsion by the tail of the sperm and the digestive enzymes allow the sperm to penetrate the zona pellucida and bind to the corona radiata underneath.  Once the sperm binds to the zona pellucida, the cortical reaction occurs. This causes the cortical granules inside the secondary oocyte to fuse with the plasma membrane of the cell, causing them to be expelled to the zona pellucida, making the matrix impermeable to sperm.

The oocyte now undergoes its second meiotic division producing the haploid ovum and releasing a polar body. The sperm then binds to the ovum enabling fusion of genetic material. One hurdle for such fertilization to overcome is that of how the gametes meet, this is typically overcome by having sperm with flagella that swim to the egg, potentially using chemotoxicity to guide them. In internal fertilization (such as in humans) a cortical reaction occurs within the egg once a cell reaches the cell membrane. This cortical reaction modifies the zona pellucida of the egg modifying the proteins on the zona and preventing any additional sperm from binding.

Implantation Once fertilization occurs a zygote is formed, this is day 1! The zygote then undergoes cleavage where the cell divides into two, four, eight etc. it is worth noting this cluster of cells does not increase in size, only in the number of cells. By day 4, there are about 16 cells, at this point the ball is known as a morolla. This then develops into a Blastocyst by day 5,

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with 32+ cells and a fluid filled cavity (blastocoele) in the middle. By day 7, the blastocyst is implanted into the wall of the endometrium. The Blastocyst implants, with the embryoblast cells close in, to the endometrium. As attachment takes place, the trophoblasts release digestive enzymes that allow the blastocyst to better insert itself into the endometrium. By the 10th day the embryo is fully embedded into the wall of the endometrium, digestive enzymes are continuously secreted by the trophoblastic cells and these help to break down blood vessels of the endometrium, ensuring that nutrients and oxygen is in good supply. Furthermore, the epithelium is rebuilt around the implantation, so the embryo is fully embedded into the uterine wall. At this point, some important structures are formed so lets review in turn:

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The Chorion is formed from trophoblastic cells The amniotic cavity is formed from the embryoblast cells, this is where the embryo will be found in the future The embryonic disc is the floor of the amniotic cavity, this goes on to be the notochord The umbilical vesicle, also formed from the embryoblast cells, goes on to form the umbilical cord.

After about 25 days the following picture can be seen:

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At this stage, the umbilical vesicle, futu...