RAP Exam 3

Who to consider a chromosome evaluation for?

-Suspected recognizable chromosome syndrome -Unrecognized pattern of 2 or more malformations -Ambiguous genitalia -Intellectual disability or developmental delay -Parents & children of persons with translocations, deletions, duplications -Stillborn infants with malformation or no recognizable reason for fetal death -Females with short stature & primary amenorrhea -Males with small testes & gynecomastia -Female with 2 or more miscarriages

Reciprocal Translocations

Chromosomal breaks on 2 different chromosomes Broken chromosomes *switch* the material that was broken Person often inherits a reciprocal translocations from the germ cell of one of their parents, referred to as *derivative chromosomes* Translocation will generate two 'der' chromosomes -Offspring may receive the normal chromosome or the derivative If the individual inherits *both* derivative chromosomes, they will be unlikely to exhibit a phenotype as they will have a balanced translocation Offspring of this individual are at high risk of chromosomal abnormality syndromes, including duplications and deletions of chromosomal regions (leads to trisomy for some regions and monosomy for others) *Highly variable between individuals*; not possible to detect phenotype in an individual that carries an unbalanced chromosomal translocation -Ones that involve larger portions of chromosome tend to produce a more severe phenotype 25% chance of having genetically normal offspring 50% chance of having phenotypically normal offspring

Infertility - Uterine Factors

Congenital malformation (septum), leiomyomas (submucous), intrauterine adhesions, possibly endometrial polyps

Combinatorial Screening

Current typical approach is 1st trimester, then 2nd trimester screens For Trisomy 21, this detects 95% of cases with false positive rate of ~5% Addition of NIPS has increased detection to >99% with false positive of <1%

Renal Changes in Pregnancy

ANATOMIC - increase in kidney size & weight Ureteral dilation usually right > left due to progesterone; dextrorotation of uterus due to sigmoid colon Bladder becomes intra-abdominal HEMODYNAMIC - GFR increases by 50% Renal plasma flow increases by 75% Creatinine clearance increases to 150-200 ml/min FUNCTIONAL - renal retention of Na+ and water leads to increase (6-8L) in total body water; 2/3 extracellular, 1/3 intravascular; increase seen in *dependent areas* Metabolic changes via kidney: -BUN & creatinine decrease (1 is insufficient) -Plasma osmolarity decreases by 10 -Increase in tubal reabsorption of sodium -Marked increase in renin & angiotensin levels, but markedly reduced vascular sensitivity to hypertensive effects -Increased glucose exertion Pregnant women are prone to upper & lower UTIs, as well as bladder rupture in abdominal trauma Renal indices drawn in a pregnant patient should fall outside the normal range: Creatinine - 0.6 (normal is 1) BUN - 3-11 (normal is 7-20) UA positive for glucose & small amounts of protein

Single Gene Disorders

AZF-Y - defective spermatogenesis CFTR - bilateral absence of vas deferens/thick vaginal mucus NR5A1 - streak gonads SOX9/SRY - sex reversal NR0B1 - hypogonadotropic hypogonadism in males CYP21A2 - virilization CYP11B1 - virilization

Balanced vs. Unbalanced translocations

Abnormalities in chromosome structure refers to the loss or duplication of *parts* of chromosomes that can occur as gametes are formed Can be broken down into: *Balanced* - rearrangement that does not produce loss or gain of chromosome material *Unbalanced* - produces a gain or loss of material Unbalanced are more likely to produce a phenotype in the individual with the abnormality; balanced are often associated with reduced fertility and pregnancy loss (very early) Inability to conceive and/or carry a fetus to term leads to the discovery of the balanced translocation

Fertilization to Implantation

Day 1 - first cleavage Day 2 - 2-cell stage Day 3-4 - 4-cell stage, 8-cell uncompacted morula (mitosis) Day 4 - 8-cell compacted morula Day 5 - Early blastocyst Day 6-7 - Late stage blastocyst (hatching) Day 8 - Implantation of blastocyst (multicellular organism) It is believed that control of fertility relies in tubal fluid that promotes fertilization Blastocyst implants into decidualized endometrium *Cytotrophoblasts* proliferate into endometrium and gain access to maternal vessels *Trophoblasts* form the 'villi' that make up the placenta

Follicles & Menopause

Decrease in estrone & estradiol levels in 5th decade of life (high FSH & LH) is associated with dropout of primordial follicles As the ovary is exhausted with primordial follicles, hormone levels will decrease FSH & LH very high due to loss of negative feedback from estradiol

Sperm Capacitation

Alters sperm membrane fluidity via removal of cholesterol & proteins/carbohydrates from the membrane that may otherwise block sites that bind to zona pellucida Change in membrane potential that permits Ca++ to enter sperm via voltage-gated mechanism to facilitate vesicle release from acrosome

Fertilization - Timeline

Egg from ovary enters FT at 9-16 days of menstrual cycle -Fertilization in upper 1/3 of tube, within 24 hours after ovulation -24-30 hours after fertilization, male & female chromosome material unite 36 hours after fertilization - 2 cells 48 hours after fertilization - 4 cells 3 days - cluster of 16-32 cells 4 days - hollow ball of 100 cells 4-5 days - zygote enters uterus 6-7 days - zygote begins to attach to wall of uterus 12-14 days - zygote is completely implanted in uterine wall

Oogenesis: secondary oocyte

Enters meiosis II due to LH signaling, proceeding to metaphase II & arrests again in fallopian tube Arrested secondary oocyte is released from the ovary at ovulation and matures in preparation for fertilization If fertilization occurs, the egg is stimulated to complete meiosis II; meiosis II is also asymmetric, producing a second polar body Two nuclei are present - one from secondary oocyte & one from spermatazoa that penetrated the egg

Hormones in labor

Estrogen increases the number of *oxytocin* receptors, leading to release of prostaglandins and uterine contractions --> dilation of cervix & distension of vagina --> stimuli from cervix & vagina --> increased secretion of oxytocin Positive feed-forward feedback leads to expulsion of fetus & placenta; breaks when baby is delivered Both maternal & fetal oxytocin levels increase spontaneously during labor, but neither increase before labor *Prostaglandins (PGE2, PGF2)* - produced by fetus, placenta & uterus to stimulate uterine contractions -E2 increases PG production -Final mediators of labor *Relaxin* - produced by placenta; increases joint laxity *Mechanical factors* - stretch and/or irritation

Estrogen:Progesterone ratio in pregnancy

Estrogens increase expression of gap junctions and cation channels (Na+ & Ca++), both of which increase uterine smooth muscle excitability (why progesterone is sometimes administered throughout pregnancy) Fetal cortisol increases the E:P ratio Ratio increases the number of oxytocin receptors & myometrial gap junctions; this explains the coordinated, effective contractions that characterize true labor as opposed to nonpainful, ineffective contractions of false labor

GI Changes in Pregnancy

High levels of circulating progesterone (smooth muscle relaxant): Increases GE reflux from relaxation of GE sphincter Constipation from delayed transit through large bowel Relaxes gallbladder musculature, leading to stasis & increased stone formation Increases N/V from delayed gastric emptying ANATOMIC - appendix is displaced superiorly & laterally; in RUQ in 3rd trimester -Sigmoid colon may enlarge due to decreased transit time; often causes rotation of uterus to the right Delayed gastric emptying creates significant risk of aspiration during intubation or loss of consciousness Increase in symptomatic gallbladder disease - laparoscopic cholecystectomy is not an option once the uterus rises above the umbilicus Difficulty in evaluation of women with upper abdominal pain in pregnancy

Noninvasive Prenatal Screening (NIPS)

Humans normally have small amount of free DNA present in circulation; after 7 weeks gestation, 2-10% of free DNA present in plasma of pregnant female is of fetal origin Isolation of cell-free DNA from maternal blood (mix of maternal & fetal DNA) -perform DNA sequence analysis, but not known if maternal or fetal Map of all sequences to specific chromosome location and statistically analyzed

Carrier Identification

Identifies individuals who do not themselves have a particular disease, but who are at risk of having a child with a particular disease Carrier testing involves individuals known to be at high risk because of family history (testing a woman with a nephew with CF), as well as in individuals with no family history Information should be offered to every pregnant woman, ideally before pregnancy Few choices available to those identified as carriers; limitations of carrier screening as well

Prenatal Genetic Testing

Identifying chromosomal abnormalities, single gene disorders, multifactorial conditions Screening vs. diagnostic

Perinatal Exposure to Infection

During vaginal delivery or with PROM, microbiota may proliferate (esp. with fever) GC, Chlamydia can infect infant's eyes (mandatory ocular prophylaxis) Active genital herpes may cause systemic infection - can occur during delivery or in early neonatal period (even from oral infection)

Cardiac Output in Pregnancy

Increases about 30-50% (4.5 --> 6 L/min) Increases by renal-mediated increase in sodium & water absorption Stroke volume *increases* by direct hormone-mediated increase in contractility Heart rate increases about 15-20bpm Systemic vascular resistance (SVR) *decreases* due to low pressure placental bed and relaxation of vascular tone Increased ventricular cardiac muscle mass & contractility increases the stroke volume - mediated by *progesterone* Increased compliance of smooth musculature of vascular system leads to decreased SVR in arterial & venous systems - mediated by *progesterone* Increased heart rate due to sinus node excitability - not sure why Many effects of altered CV system mimic low output congestive heart failure --> peripheral edema, changes in heart sounds (S3 gallop, flow murmur), dyspnea, increased JVD, abnormal cardiac silhouette on CXR, EKG chnanges These changes occur by 6 weeks gestation and persist several weeks postpartum

Genetic Counseling

Indications include family/personal history of birth defect, genetic condition, intellectual disability/learning difficulty, adult onset condition, recurrent miscarriage/stillbirth/infant death Also, pregnant women who are >35yo at delivery, increased risk of abnormal baby, potential teratogenic exposures, specific ethnic groups, have a serious health condition, part of consanguineous union Ethical dilemmas arise with confidentiality, informed consent, more than one patient, testing in adolescents & children, prenatal testing for adult onset disorders, disclosure issues (non-paternity) Ethics split into: Section 1 - GCs themselves 2 - GCs & their clients 3 - GCs & their colleagues 4 - GCs & society

Translocations - general

Interchange of genetic material between nonhomologous chromosomes Most common chromosomal aberrations seen Commonly broken down into Reciprocal & Robertsonian translocations

Robertsonian Translocations

Involve only *acrocentric* chromosomes (13, 14, 15, 21, 22); involves loss of short arms & fusion of long arms at the centromere Acrocentric chromosomes have small p-arms with redundant genetic material Two small p-arm resultant chromosome will be lost Individuals are phenotypically normal due to loss of only redundant (rRNA) material; such people do, however, have *one fewer chromosome* Offsprings from these individuals often exhibit deletions or duplications Also assoc. with reduced fertility/pregnancy loss Six possible gametes between parents with Robertsonian translocation; 3 are compatible with survival (normal, balanced translocation, Down's) and 3 are not (monosomy/trisomy) 1/3 chance for every offspring that goes to term; 1/6 chance in every conception (half are lethal) Responsible for 5% of Down Syndrome cases; risk of *recurrence* is much higher in this family

Amniocentesis

Involves insertion of needle transabdominally into amniotic sac with removal of 20-30mL of amniotic fluid Fluid contains living cells shed by the fetus Usually performed between *16-20 weeks* after LMP Tests can be performed on both cells and fluid Utilized U/S guidance Advantageous for isolation of amniotic fluid & fetal cells Primary risk is fetal loss; 1-2% risk

Susceptibility Testing

Involves looking for genetic mutations that confer a higher risk for developing disease Disorders are usually multifactorial -tests have variable specificity & sensitivity -examples include Apo-E4 (Alzheimer's) and BRCA1/2 (breast cancer) Test results of this type do not mean that disease will inevitably occur or remain absent Ethical issues involve education, test interpretation, potential for increased monitoring

Infertility - Ovulatory Defects

Measurement of serum progesterone in mid-luteal phase confirms ovulation No value in measuring thyroid fxn or prolactin in women with a regular menstrual cycle in absence of galactorrhea or thyroid symptoms *BBT* - thermogenic potential of progesterone Rises with ovulation; represents 12 or more days to menses *Progesterone* - 3-4ng/mL 7-8 days post-ovulation Signifies luteal phase fxn *LH excretion* - ovulation prediction (24-48 hours) Starts 2-3 days before LH surge Late afternoon testing with concentrate urine Day of surge and following 2 *Ultrasound* Anovulation & oligoovulation are among the most common causes of infertility; more common in women who have extremes of body weight, exercise excessively, struggle with eating disorders

Congenital Rubella Syndrome

Mild viral rash in children/young adults; vaccine preventable since 1969 Maternal viremia transmitted *transplacentally* Severe consequences, especially before 16 weeks Early pregnancy has greatest complications (abortion, stillbirth, CRS) via cell destruction & mitotic arrest *Triad of symptoms* - cataracts, hearing impairment, congenital heart malformation (patent ductus arteriosus, pulmonary stenosis) Titers may be used to confirm protection prior to pregnancy; rubella-specific IgM, IgG tests distinguish current from prior infection in mother Congenitally-infected infants will develop IgM Efficiency of transplacental microbe transfer varies with length of gestation; *first trimester is time of greatest fetal structure development*

Edward Syndrome (Trisomy 18)

Most common chromosomal abnormality in stillborns with congenital malformations <5% survive to term Mosaicism is rarely seen 90% due to maternal nondisjunction Advanced maternal age Prominent occiput, small mouth, micrognathia, shield chest, wide-set nipples, dysplastic ears, clenched hands, flexed big toe

Immune System Changes in Pregnancy

NOT an immunosuppressed state; while various pathogens can affect the fetus, overall, the maternal organism has healthy immune function Placenta has increased numbers of NK cells, T-cells and macrophages Humoral level is unclear as progesterone is an immunosuppressant

What causes physiological adaptations in pregnancy?

Need for delivery of enough O2 and nutrients to fetus, while preserving maternal function Anticipation of blood loss at delivery Pregnancy is a state of supra-optimal physiologic function, but with low maternal reserve for insults; normal lab values can differ markedly

Syndromes of Reduced Fertility

Noonan - PTPN11, SOS1 - delayed puberty, cryptorchidism in males Kallmann - ANOS1 - absent puberty, hypogonadotropic hypogonadism, anosmia Denys-Drash/Fraser - WT1 - ambiguous genitalia in males ADPKD - PKD1 - epididymis, seminal vesicle cysts Androgen Insensitivity Syndrome - AR - testicular femininization in 46XY females Swyer Syndrome - SRY/MAP3K1/DHH/NRFA1 - streak gonads in 46 XY females

Congenital Parvovirus B19

Only 5% develop fetal complications Miscarriage secondary to maternal anemia (virus replicates in red cell precursors) Replicates in fetal cells, causing non-immune hydrops (edema) and fetal death Not vaccine preventable; titers can be tested to determine risk, immunity or infection (IgG, IgM) IVIG has been used for treatment Intrauterine fetal transfusion indicated for hydrops U/S monitoring may be useful for hydrops diagnosis Serial middle cerebral artery Doppler flow measures to track disease

Oogenesis - general

Oocyte differentiation; coordinated with folliculogenesis Primordial germ cells (PGCs) -*-> oogonium -*-> primary oocyte -**-> secondary oocyte * - mitosis ** - meiosis I (under control of LH) Primary oocyte at same time as primordial follicle Secondary oocyte at same time as Graafian follicle Apoptosis occurs at nearly every step to reduce the pool; PGCs, oogonia & primary oocytes undergo apoptosis or autolysis prior to birth Primary oocytes undergo autolysis throughout life and very few will become a dominant follicle that responds to LH to become a secondary oocyte Vast majority of secondary oocytes never complete meiosis II due to lack of fertilization

Gamete Intrafallopian Transfer (GIFT)

Ova & sperm are mixed outside the body and transferred into the FT via laporoscopy Fertilization takes place inside body Requires functional tubes

Zygote Intrafallopian Transfer (ZIFT)

Ova fertilized in the lab Transferred into tube within 24 hours of fertilization Requires functional tubes

Newborn Screening

Shortly after birth to identify genetic conditions; identify conditions that are treatable in order to begin treatment ASAP to prevent serious handicaps CRITERIA: -treatment is available -early treatment can reduce/eliminate permanent damage -disorder would not be revealed in newborn without a test -rapid & economical lab test is available that is highly sensitive & reasonably specific -condition is frequent and serious enough to justify expense of screening -societal infrastructure is in place

ß-hCG signal

Signal that pregnancy has been achieved Upon successful implantation, chorionic gonadotropin (hCG) is produced by *syncytiotrophoblasts* and maintains the corpus luteum hCG levels peak around 10 weeks gestation & remain elevated throughout Placenta takes over much of endocrine function (lutealplacental shift) around Week 8 of gestation hCG uses the same receptor as LH, and substitutes for LH to drive progesterone production by the corpus luteum during early pregnancy

Intracytoplasmic Sperm Injection (ICSI)

Single sperm is injected directly into a mature oocyte -Fertilized egg then used for IVF/ZIFT -Corrects for sperm-quality related male factor infertility -May be used for couples who have not conceived with other assisted reproduction techniques

Artificial Insemination

Used to treat male factor infertility, retrograde ejaculation, neurologic impotence, sexual dysfunction Sperm used for insemination may be the male partner's or donated -methods include intracervical insemination (ICI) and intrauterine insemination (IUI) -success rates vary from 6-24% per cycle

Placenta

Provides: O2 & nutrients Immune factors (IgG, cytokines) Cells with potential immune consequences (similar to BBB) Uterine decidua has an abundance of immune cells Infectious agents may cross the placenta

Genetic Counseling - Issues

*Human germline editing* - NSGC only supports editing in a manner that is regulated, transparent and equitable *Prenatal testing for Adult-onset conditions* - deferring prenatal genetic testing if pregnancy management will not be affected *Incidental findings in Genetic testing* - should identify and disclose to physicians *Reproductive Freedom* - decisions should be unbiased and comprehensive, free from discrimination or coercion

Respiratory Changes in Pregnancy

*Increased delivery of O2 to pulmonary vasculature* *Increased delivery of O2 to tissues* *Continue normal function of mother* UNCHANGED - respiratory rate, vital capacity DECREASED - functional residual capacity, expiratory reserve volume, inspiratory reserve volume, residual volume, total lung capacity INCREASED - inspiratory capacity, tidal volume (by 30-40% - progesterone-mediated; pts take slow, deep breaths) BLOOD GASES: pH - 7.44 (increased, but normal); slightly alkaline due to renal excretion of HCO3 --> urinary frequency PCO2 - decreased; relative hyperventilation; minute ventilation increases; relative *respiratory alkalosis* HCO3 - normal PO2 - increased; hyperventilation, increased O2 carrying capacity; normal O2 in pregnancy is frequently abnormal DISSOCIATION CURVE - shifted to the *right* Fetal Hgb has higher O2 affinity than adult Hgb; primarily due to reduced affinity to 2,3-bisphosphoglycerate and increased production of DPG Normal pregnant woman has compensated respiratory alkalosis & diminished pulmonary reserve Relatively hyperoxygenated (normal non-pregnant oxygen levels are abnormal) Particularly susceptible to pulmonary insults Primarily due to *progesterone*

General Ethical Issues in Genetic Testing

*Lack of knowledge* - involves consumers & physicians; unnecessary genetic testing, misinterpretations, failure to refer to counselor *Direct to Consumer Testing* - without involvement of healthcare professional -informed consent, interpretation of results, further use of genetic information *Discrimination* - insurance, employment, law enforcement

Metabolic Changes in Pregnancy

*O2 consumption* - basal metabolic rate increases by 20% in pregnancy; this creates more waste *Regional blood flow* - increases to skin to eliminate heat & to kidney/liver to eliminate waste Pregnant patients often experience temperature intolerance and perception of fever; does not change core temp (only skin) -Basal body temp slightly increased -Caloric requirements increase by 300 kcal/day -Pts can lose weight normally in 1st trimester

Ovum vs. Sperm

*Ovum* - fertilization lifespan of ovum is 24-36 hours; receptivity of endometrium is days 16-19 of a 28-day cycle *Sperm* - sperm reach the caudal epididymis approx. 72 days after initiation of spermatogenesis; preservation of optimal sperm function during storage requires adequate testosterone levels & maintenance of normal scrotal temp Each ejaculate contains an average 200-400 million sperm, of which only a few hundred achieve proximity to the egg within 15 mins -Sperm most active within 48 hours after ejaculation -If ovulation is not occurring or approaching, the sperm find themselves in very hostile surroundings; vagina's acidity causes sperm to perish within hours, thick cervical mucus, uterine entrance is closed

Hematological Changes in Pregnancy

*Plasma Volume & RBC Mass* - plasma volume increases 50% via renal-mediated retention of water & sodium RBC volume increases by 30% via hormonal stimulation of bone marrow & erythropoetin production by kdiney *Physiological anemia of pregnancy* - mean Hgb is lower (10.5-13.5) and Hct is lower (28-40); not typically symptomatic *Expansion of circulating RBC mass* - hormonal impact on bone marrow Effect of progesterone & prolactin on kidney to produce more erythropoietin Expands by 15-20% *Lower affinity of maternal Hgb for O2* - increased circulating levels of 2,3-BPG Facilitates dissociation of O2 from Hgb at high levels in tissues *WBCs* - increase, but still within normal limits; function is unchanged *Platelets* - decreases, but still within normal limits; function is diminished See nose & gum bleeding often in pregnancy *Coagulation* - hypercoagulable state due to increased fibrinogen, Factors VII-X; placenta produces plasminogen activator inhibitor Life-threatening thromboembolic disease more common during pregnancy; *leading cause of maternal mortality* Tx - coumadin, heparin *Blood loss is well tolerated* - maternal vital signs do not change for blood loss up to 1,500mL Vital signs cannot be relied upon as accurate indicator of ongoing blood loss Diminished maternal reserve once 1,500mL is reached

Infertility - Cervical Factors

*Postcoital test (Sims-Huhner)* - intercourse (2-12 hours) for test -look at presence of >5 sperm in cervical mucus, spinnbarkeit, sperm agglutination Infrequently used now

Primary vs. Secondary Infertility

*Primary* - inability to conceive after one year of unprotected intercourse for a woman <35yo, or after 6 months if >35yo *Secondary* - inability of woman to conceive who was previously able to do so Affects 1/12 couples, or 24 million women; usually 1/3 men, 1/3 woman, 1/3 unexplained; 20-40% of couples have multiple causes MALE - azoospermia, compromised spermatogenesis FEMALE - endometrial adhesions, endometriosis, drugs, alcohol abuse, obesity, radiation, lack of exercise, pollution, unhealthy lifestyle *Singlemost important determinant of couple's fertility is age of female*; conception peaks at 20-24yo; older women (>45yo) have >90% aneuploidic eggs and a higher chance of miscarriage

Primary purpose of genetic screening

*Provide information*, not reduce the incidence of diseases/syndromes Benefits include: -Level of reassurance when screening is negative -Accurate assessment of actual risk -Options for how to manage a known risk - electing not to proceed with pregnancy, electing pregnancy termination for an affected pregnancy, choosing IVF -Allow physicians to plan management for high risk pregnancy -Allow families to prepare for birth of affected offspring

Entry of Sperm

*Step 1* - penetration of ECM of cumulus by sperm membrane hyaluronidase (PH-20) *Step 2a* - binding of sperm ZP3 receptor to ZP membrane glycoprotein ZP3 *Step 2b* - ZP3 binding induces release of acrosomal enzymes *Step 2c* - sperm secondarily bind to another zona pellucida protein (ZP2) *Step 2d* - zona pellucida is then digested and sperm swim through to the egg *Step 3* - fusion of sperm & egg membrane takes place; contents of sperm cell enter the oocyte (DNA) *Step 4* - PLC/IP3/Ca++ signaling cascade *Step 5* - cascade activates exocytosis of enzyme-filled vesicles (Cortical granules); enzymes modify both ZP2 & ZP3 glycoproteins of the zona pellucida, such that ZP2 can no longer bind *Step 6* - flagellum & mitochondria disintegrate (mitochondrial DNA is maternally derived) Membrane, called *pronucleus*, forms around sperm DNA as newly activated egg completes the second meiotic division Once the oocyte is fertilized, a large fertilization wave of intracellular calcium sweeps across the oocyte in ~40 seconds; also an extracellular zinc spark due to rapid efflux

Traditional vs. Gestational Surrogacy

*Traditional* - IUI using male's sperm & surrogate's ovum -Carried by surrogate & regulated by contract -Adopted by female partner after birth *Gestational* - IVF/GIFT/ZIFT using both male & female's material -Carried by surrogate & regulated by contract -Pre-birth court order used to list both male & female partner as parents' on the birth certificate

Unexplained Infertility

10-30% incidence; laparoscopy is necessary

First Trimester Screening

11-13 weeks; screening in maternal blood for: -U/S analysis of nuchal translucency -Pregnancy-associated Plasma Protein A (PPP-A) -Human chorionic gonadotropin (hCG) *Nuchal Translucency* - ultrasound measurement of thickness of echo-free space between skin & soft tissue overlying the dorsal aspect of cervical spine Increased in Trisomy 13/18/21 & 45 X PPP-A decreased in all trisomies hCG increased in Trisomy 21, decreased in 13 & 18

Congenital HIV

25-30% transmission without treatment; with treatment, <2% Worry about complications from HAART Clinical studies indicate HAART during pregnancy does not affect weight, prematurity, low APGARS Prevention depends on testing and ART *Keep HIV titer low to prevent transplacental transmission*

Down Syndrome (Trisomy 21)

75% end in pregnancy loss 90-95% due to maternal nondisjunction 75% occurs in Meiosis I 2-4% are mosaics 5% due to Robertsonian translocations Flattened nose, upward slanting eyes, single palmar crease, short fifth finger, widely separated 1st and 2nd toes, increased skin creases in feet

Patau Syndrome (Trisomy 13)

95% result in pregnancy loss Advanced maternal age Mosaicism is rare 90% due to maternal nondisjunction Small head, absent eyebrows, cleft lip/palate, dysplastic ears, clenched hands/polydactyly, abnormal testes

Oogenesis: PGCs --> secondary oocyte

Begins during embryogenesis with migration of primordial germ cells to developing ovary; PGCs differentiate into oogonia, which proliferate via mitosis to build a stockpile of millions of oogonia by 20 weeks gestation Prior to birth, individual oogonia will undergo apoptosis (atresia) or differentiate into primary oocyte Primary oocytes enter meiosis I and arrest in Prophase I ('diplotene arrest') Meiosis resumes for some primary oocytes at *puberty* Once menarche initiates at puberty, a small number of oocytes each month complete meiosis I under control of LH to become secondary oocytes -conclusion of meiosis I is asymmetric, in that two cells produced differ greatly in size (secondary oocyte & polar body)

Infertility - recommendations

BMI of >29 is associated with reduced fertility in both men & women Folic acid supplementation prior to conception and up to 12 weeks of conception Rubella immunity should be checked - if recently vaccinated, then advise to avoid pregnancy for at least 1 month after vaccination Sexual intercourse every 2-3 days Timed intercourse to coincide with ovulation causes stress - not recommended Smoking reduces women's fertility & semen quality Excessive alcohol is detrimental to semen quality and may cause ED

Chorionic Villus Sampling (CVS)

CVS involves isolation of tissue from the extra-embryonic portion of the blastocyst Can be done transvaginally or transabdominally Usually performed between *10-13 weeks* after LMP (earlier than amnio) U/S guidance is critical Advantageous for earlier diagnosis in pregnancy when termination is an option Times when extra-embryonic mosaicism is evident that may or may not be present in fetus Primary risk is fetal loss; 2-5% risk

Monosomy

Can occur for any of the autosomes, but is always embryonic lethal; only monosomy compatible with live birth is X (Turner's) 99% result in pregnancy loss 60-80% due to PATERNAL nondisjunction 50% of surviving Turner Syndrome offspring are mosaics

Regional Blood Flow Redistribution in Pregnancy

Despite presence of fetus, blood flow to brain & essential organs is always preserved When CO falls, blood is shunted to brain and other vital organs, away from uterus & placenta, causing vagally-mediated reflex fetal bradycardia

Meiosis

Diploid --> haploid Prophase, Metaphase, Anaphase, Telophase

Congenital Malaria

Falciparum more of concern, Vivax less so VAR2CSA protein binds to placental chondroitin sulfate (syndecan-1) Infected erythrocytes bind to placenta and cause *placental congestion* with reduced perfusion Major concern is LBW, but may cause spontaneous abortion, preterm birth, maternal anemia Individual risk greater when acquired in first pregnancy; intermittent prophylaxis with sulfadoxine-pyramethamine, folate supplementation and iron

Parturition - general

Full term at 37 weeks; signs heralding approaching labor include: *Lightening* - settling of fetal head into brim of pelvis *Braxton Hicks contractions* - sporadic, ineffective, painless (usually) contractions for a few weeks prior to labor *Cervical effacement* - cervix becomes softer and thinner Key inciting event of labor is unknown

Congenital Listeriosis

Gram (+) aerobic rod; contaminated meat, cheeses, unpasteurized milk, unwashed fruits/veggies Mother gets flu-like symptoms, bloodstream invasion, meningitis may develop *Maternal bloodstream infection infects placenta (multiple microabscesses of yellowish-white lesions)* Mother may abort or deliver a stillborn; live babies have hepatosplenomegaly, respiratory distress, rash on trunk and extremities Miliary granulomatous lesions of various organs (granulomatosis infantiseptica) Listeria can also infect cervix and cause ascending infection, leading to chorioamnionitis and amniotic fluid infection No treatment in asymptomatic pts who ate recalled product Antibiotics not prescribed for otherwise healthy individuals, but may be prescribed to avert fetal infection

Intrapartum/Postpartum insults

Group B Strep, Chlamydia, Neisseria, CMV (rare), Herpes

Prematurity

Leads to babies who are immunologically immature with respiratory problems, vision impairment, mental handicap, failure to thrive NICU can save babies' lives, but at high economic impact Surviving premature babies can suffer consequences that last throughout life 1/8-11 pregnancies in the US

Presymptomatic Testing

Looking for genetic mutations that have a high penetrance (usually AD) -need to be highly sensitive & specific Can identify individuals who we now know are very likely (virtually 100%) to develop devastating & debilitating diseases at some point in the future Ethically, respect for personal autonomy, informed consent, reluctance to test children and prenatal testing for late onset disorders are all factors

Infertility - therapy

MALE FACTOR: Urology consult Donor sperm insemination Intrauterine insemination (IUI) IVF-Embryo transfer (IVF-ET) IVF with ICSI (intracytoplasmic sperm injection) FEMALE FACTOR: -Poor or lack of cervical mucus - consider IUI low-dose estrogen -Anovulation - *Clomiphene Citrate* used to treat mildly disordered ovulation & luteal-phase insufficiency Establish tubal patency and sperm adequacy before use In appropriately selected patients, 80% ovulate and 40% conceive; cumulative conception rate is 60-75% Multiple rate is about 10% After 6 months, women should move on to more aggressive therapy *Injectable Gonadotropins* - when women exhibit resistance to clomiphene OR multiple oocytes are desirable to ovulate (multiples rate as high as 40%) -Tubal occlusion - corrective surgery and/or IVF

Important CV points in pregnancy

MUST: -Accommodate both fetus & mother -Maximize delivery of O2 and metabolic substances to the fetus -Allow normal function of mother without undue stress -Be reversible -Prevent direct transfer of maternal blood to fetal circulation and vv, to avoid overwhelming immune response -Allow for maternal blood loss at delivery and postpartum

ART Risks & Complications

Ovarian Hyperstimulation Syndrome (OHHS) Multiple gestations - >43% rise in multiple births linked to ART; more likely for higher order births to be born prematurely (increased financial cost as well) Women who conceive as a result of ART are at increased risk for mood disorders during pregnancy & early pregnancy difficulties -Women with multiple newborns have increased risk for postpartum depression -Children born after ART have increased risk of birth defects Providers should ensure that clients understand all options and cost; very expensive

In Vitro Fertilization (IVF)

Ovarian hyperstimulation Retrieval of follicles under U/S guidance Fertilization in lab with partner's washed sperm Maturation for 3-5 days in lab Transfer of embryo(s) into uterus Embryos may be frozen for future transfer

Supine Hypotension Syndrome

Overt Caval Compression Fall in venous return by compression of IVC by the gravid uterus leads to a fall in CO & syncope Often accompanied by maternal bradycardia Can also cause fetal bradycardia Easily resolved by placing pt in left lateral decubitus position Occurs in 8-15% of pregnant women - sweating, maternal hypotension, N/V, pallor

Infertility - treatment options

Ovulatory dysfunction - weight modulation, ovulation induction, IVF/GIFT/ZIFT Tubal factor infertility & endometriosis - surgery correction, IVF Uterine factor - surgical correction Cervical factor - intrauterine insemination, IVF/GIFT/ZIFT Male factor - direct sperm retrieval, treatment of hyperprolactinemia/hypogonadism, antibiotics/steroids, IVF/GIFT/ZIFT Unexplained infertility - ovulation induction, IUI, IVF/GIFT/ZIFT Surrogacy, gestational surrogacy, adoption

Infertility - evaluation

Partners should be seen together; counseling is important & routine examination is usually not necessary; take an occupational history Primary evaluation components include male, ovarian, cervical, tubal and uterine factors. MALE - physical examination for obesity, H-P axis failure, abnormalities of testes, epididymis, prostate, penis, vas deferens, or varicocele Semen analysis - 60% have normal morphology; others may be due to Klinefelter's, endocrinopathies, varicocele, obstruction, infection, hypogonadism, defect in spermatogenesis Anatomical evaluation

Blood Pressure in Pregnancy

Peripheral vascular resistance (PVR) falls due to low pressure placental vascular bed & progesterone effect on smooth muscles of blood vessels Blood pressure falls in 2nd trimester, then returns to normal in 3rd (5-10mmHg systolic & 10-15mmHg diastolic) Beware of 'normal' blood pressure in a pregnant patient; a normal or slightly elevated blood pressure in a pregnant patient may be a sign of impending difficulty Low blood pressure may not represent any serious clinical concern & should be viewed in context of heart rate and mental status

Maternal-Fetal-Placental Endocrinology

Placenta is major source of progesterone & estradiol during pregnancy, beginning around Week 8 Placenta synthesizes both, but lacks enzymes required for the full pathway Placenta relies on maternal cholesterol as its substrate for progesterone production; fetal death has no immediate influence on progesterone production, suggesting fetus is negligible source of substrate Placental estrogens are derived from fetal androgens (maternal, fetal adrenal & liver), primarily DHEAS PLACENTA CAN: -make progesterone via 3ß-hydroxysteroid dehydrogenase -make estrogens via 3ß-OH, 17ß-OH, aromatase PLACENTA CANNOT: -synthesize cholesterol -make androgens (lacks 17-alpha-hydroxylase & 17,20-desmolase)

Congenital Zika Virus

Pregnant women of greatest concern Guillain-Barre in adults in 0.02-0.06%, but microcephaly in 0.5-2.1% Vector control is most advantageous now Features include microcephaly, brain calcifications, retinal pathology, congenital contractures, extremity hypertonia Risk decreases as pregnancy continues

Congenital Cytomegalovirus

Propensity for latency; infants infected in utero (early gestation) are SGA, intracranial calcifications and microcephaly, hearing loss, mental retardation Infants infected later have visceral disease with hepatitis, pneumonia, thrombocytopenia, purpura Testing for recent infection is IgM + IgG with low avidity PCR for amniotic fluid is recommended, but not fetal blood Congenital CMV's risk is mainly with primary maternal infection (seronegative mother); deafness > IQ below 70 > cerebral palsy Infection may be asymptomatic with later hearing/vision issue and mental delay Symptoms include placental thickening, hepatosplenomegaly, kidney pathology, megaloureter, intracranial calcification, microcephaly, ventriculomegaly, ascites, hydrops, petechiae/purpura 75% of cases are reactivation or due to a new strain; amniocentesis for viral PCR or saliva PCR for newborn Gancyclovir for immune-suppressed patients

Inflammatory factors of premature birth

Prostaglandins cause changes to cervix and initiate uterine contractions; short cervix is also associated with amniotic bacteria Infectins elicit inflammatory cascade IL-6 & TNF-alpha are assoc. with preterm birth Gene polymorphisms compromise immunity, allowing more aggressive infections Some polymorphisms dysregulate inflammation at anti-inflammatory level Bacterial vaginosis assoc. with premature birth (CST4)

Congenital Toxoplasmosis

Raw meat (pork), veggies; cats are natural reservoir Risk to fetus is greatest when contracted earlier in pregnancy Transplacental passage is greatest later in pregnancy Maternal symptoms are mild (lymph node swelling, headache, fatigue, fever, sore throat) Fetal consequences are chorioretinitis (blindness), hydrocephalus, brain calcification (mental retardation) Anti-Toxo IgM used to detect current infection in amniotic fluid; in utero treatment has not proven effective

Assisted Reproductive Technology

Requires controlled ovarian hyperstimulation, retrieval of oocytes & IVF/embryo transfer Procedures include: IVF-ET (In Vitro fertilization - embryo transfer) - placing gametes & subsequent embryo in uterus GIFT (Gamete intrafallopian transfer) - placing unfertilized oocyte and sperm in FT ZIFT (Zygote intrafallopian transfer) - placing gametes & subsequent embryo into FT ICSI (Intracytoplasmic sperm injection) Indications include: Tubal disease, male-factor infertility, endometriosis, premature ovarian failure, PCOS, immunologic infertility, unexplained infertility

Infertility - Tubal Factor

Risk factors include PID, ectopic pregnancy (increases 6x) *Hysterosalpingogram* - 2-5 days after menses 1-3% infection rate high risk False positive obstruction rate of 15-30% *Laporoscopy* - chromotubation with indigo carmine; possibility of treatment

Organisms with potential for fetal & neonatal damage

STORCH Syphilis Toxoplasmosis Other (parvo, listeria) Rubella CMV Herpes/HIV

Screening vs. Diagnostic Test

Screening - represent a reassessment of risk based upon application of test Diagnostic - can follow positive screens in order to provide a far more definitive yes or no answer Prenatal screens & diagnostic tests are *always voluntary* and the decision to proceed must always be with the family; couples need to be informed of benefits, risks and limitations Screens: Typically minimally invasive and low cost Risk to fetus and mother is generally low Offered to all females during pregnancy Many screens have high false positive frequencies Diagnostics: Usually more invasive & have higher risk Higher sensitivity & specificity with lower false negatives & positives Such tests are a follow-up option after a positive screen

Corpus luteum

Temporary endocrine gland that secretes progesterone and estrogen, suppressing LH & FSH release Progesterone is the main hormone in the early stages of pregnancy Ovulation causes proliferation of theca & granulosa cells and lipid accumulation - falling LH levels cause corpus luteum to degenerate to corpus albicans around Day 24 If pregnancy is achieved, the corpus luteum exists until Week 8 of gestation ß-hCG is the signal that pregnancy has been achieved, secreted by the corpus luteum

Predictive genetic tests

Tests that are performed on healthy or apparently healthy individuals with the goal of identifying their risk for developing disease in the future Two types: Presymptomatic testing Susceptibility testing

Diagnostic tests for infertility

Tests with established correlation with pregnancy: semen analysis, tubal patency by HSG or laparoscopy, mid-luteal serum progesterone for diagnosis of ovulation Tests which are not consistently correlated with pregnancy: zona free hamster egg penetration tests, postcoital test, antisperm Ab assays Tests which seem NOT to correlate with pregnancy: Endometrial dating, varicocele assessment, chlamydial testing

Trisomies

Trisomies for all chromosomes have been seen except for Y-chromosome; four are associated with live birth: 21, 18, 13, X Incidence increases with advanced maternal age Pregnancy loss due to trisomies increases as well X-chromosome due to occurrence of X-inactivation; if trisomy X, only 25 genes are present in condition (PAR1/2) 13, 18, 21 all have the lowest number of genes out of all chromosomes; why they are surviving at a higher rate Trisomy is commonly cause by *meiotic disjunction*; a mosaic pattern indicates a *mitotic disjunction*

Inversions

Two breaks occurring with intervening DNA subsequently reinserting, but in an inverted fashion If it includes the centromere --> *perIcentric* If it does not --> *parAcentric* Inversions are balanced rearrangements; as such, they only rarely cause a recognizable phenotype in the carrier Do cause an inability of the homologous chromosomes to pair normally during Meiosis I To pair successfully, the chromosomes must loop; crossing over within the loop can lead to loss or gain of genetic material in the resulting offspring, and reduced fertility if the loss/gain is not compatible with life All depends on *where* the crossover event occurs; results in different monosomies, trisomies, etc.

Prenatal Screening

Two components: -U/S examination of fetus -Biochemical analysis of maternal blood for proteins & hormones Recent introduction of new screening tools *U/S fetal exam* - can detect many fetal malformations, as well as enhance precision of amnio & CVS *AFP screening* - first expressed in yolk sac & later in fetal liver; similar to albumin -AFP highest in 1st trimester and declines -Failure of neural tube to develop can result in chronically high levels of AFP -AFP levels are tested whenever amniocentesis is done *MSAFP* - maternal serum alpha-fetoprotein; small, but detectable amounts of AFP cross placenta & enter maternal blood -can be used to measure levels of AFP in amniotic fluid -tested by drawing maternal blood; fetal conditions can cause high and low MSAFP levels Failure of neural tube closure (spina bifida) elevates MSAFP; U/S helps increase accuracy Trisomies tend to have low MSASP values, but with lots of overlap (not confirmatory; need U/S to increase sens/spec) *Most common cause of abnormal MSAFP is incorrect estimate of fetal age*

Preimplantation Genetic Diagnosis (PGD)

Two important steps: -IVF -Testing of embryos derived from IVF Provides an option to individuals opposed to pregnancy termination; typically an option when a known and serious genetic disorder is possible in a conception Process starts with in vitro growth of a fertilized embryo to the 8-16 cell stage; a single blastomere is removed & tested for the disorder in question RISKS: molecular analysis of single cells is challenging -accuracy of testing is not as high as amniocentesis or CVS -frequency of false negatives - 1% -false negative could result in implantation of affected embryo -controversy with discarding of embryos not used for implantation

Fertilization

Typically occurs in the *ampulla* of the FT; ovum must be fertilized within 24-48 hours if conception is to result For 48 hours around ovulation, cervical mucus is copious, nonviscous, slightly alkaline and forms a gel matrix that acts as a filter and conduit for sperm Male ejaculate delivers spermatazoa to vagina near the cervix; transport is largely dependent on female reproductive tract & independent of swimming in the uterus Estrogens aid sperm in 2 ways: -Cervix produces watery mucus -Contractions of myometrium to propel sperm upwards towards oviduct (cervical-to-fundal contractions) Sperm undergo capacitation in the female reproductive tract Sperm begin appearing in outer 1/3 of FT within 5-10 mins of coitus; approx. 200 reach distal tubule

Fetal Blood Flow

Umbilical vein carries *oxygenated blood to the fetus* Umbilical arteries carry *deoxygenated blood away from the fetus* Ductus Venosus - oxygenated blood passes the liver Foramen Ovale - shunts oxygenated blood from right atrium to left atrium Ductus Arteriosus - shunts blood away from high pressure non-functional lungs Placenta --> umbilical vein --> ductus venosus --> IVC --> right atrium --> foramen ovale --> left atrium/ductus arteriosus

Viruses that cause minor issues in fetus

VZV, Enterovirus, Measles, Echovirus, LCMV, HepB/C, Adenovirus, Ebola, Zika

Ascending Infection

Via genital microbiota (endogenous, exogenous); Bacteria include *Listeria, Group B Strep* Barriers include cervical plug, chorioamniotic membranes Intra-amniotic infection with membrane rupture (PROM) Prolonged labor Chorio-amnionitis pathway Fetus swallows in utero (GI infection) Also possible with intact membranes, but less common Bacteria can reach eyes, ear canal (meningitis), skin (pustules), cord (funisits) Inflammatory cytokines are linked to labor; inflammatory events are involved in final common pathway to preterm labor Chorioamnionitis - particular concern is *GBS* --> respiratory distress, significant mortality *Screening & intrapartum Abx treatment is used* Post-partum infection is a greater risk when amniotic cavity is infected before or during labor, including endometritis, endomyometritis or wound infection; U/S detects *funneling* as risk factor

Hematogenous (Transplacental) Spread of Infection

Via the maternal bloodstream Barriers include the maternal host defense Fetal circulation is separated from the maternal circulation by a single layer of cells --> fetal blood can become infected Bacteria include *Listeria, Treponema* Parasites include *Toxoplasma, Plasmodium* Viruses include *Rubella, CMV, Parvovirus B19, VZV (rare), Enterovirus (rare), HIV, Zika, Ebola* Examples where mother is infected, but fetus is not: VZV Pneumonitis - only 14% mortality in 3rd trimester Measles Pneumonitis (Rubeola) - possible spontaneous labor, preterm birth, LBW Examples where fetus may not be compatible with term carriage: Influenza - ARDS UTI/asymptomatic bacteriuria - higher risk of prematurity, LBW, pyelonephritis

Second Trimester Screening

Week 16-18; Quad screen of MSAFP, unconjugated estriol, hCG & inhibin A Estriol low in all Trisomies AFP low in all Trisomies and markedly high in neural tube defects hCG high in 21, low in 13 & 18 Inhibin A is high in Trisomy 21

Weight gain in pregnancy

Weight gain & pre-pregnancy weight are both directly related to infant birthweight Average weight gain includes: Normal weight for height - 25-35lbs Underweight women - 28-40lbs Overweight women - 15-25lbs Multiple gestations - 35-45lbs (4-6 in first trimester, 1.5/week in 2nd and 3rd) Fluid retention is a significant contributor, especially in late 3rd trimester; often does not resolve until 2 weeks postpartum Only 40% of total weight gain in pregnancy is due to products of conception: Fetus - 7.5lbs Placenta & amniotic fluid - 3lbs Blood volume - 4lbs Breasts - 1-2lbs Maternal fat - 4lbs

Congenital Syphilis

When T. pallidum crosses early, half of pregnancies will be lost Surviving infants develop rhinitis, fever/rash, condyloma lata, saddle nose, sabre shins, mulberry molars Late manifestions of blindness/deafness, mental impairment Serologic testing for syphilis is recommended for screening; treatment (penicillin) is initiated during pregnancy Desensitization if allergic