In the Name of God Obstetrics Study Guide 3 Mitra Ahmad Soltani 2008
Iranian Council for graduate Medical Education. Board and pre-board Exam questions for OBS and Gyn .2001-2006
Panda S . IUGR. Department of Obstetrics & Gynecology Medical College of India 2002
Pritchard JA, MacDonald PC, Gant NF. Williams Obstetrics . 22 nd ed. New York, NY: McGraw-Hill; 2005.
Tan T and Yeo G. IUGR. Current Opinion in Obstetrics and Gynecology 2005, 17: 135-142
Butler J. postterm delivery. emedicine. June 19. 2006
Gaufberg S. Abruptio placenta. emedicine. Aug 29. 2006
Gibson P. HTN in Pregnancy. emedicine. DEC 13 2007
Hernandez E . GTN. emedicine. Jan 26, 2007
Marinnan G. Placenta Previa. emedicine. Aug 26. 2005
Ross M. preterm. emedicine. 31 may 2007
Pictures and material of multiple pregnancy are adapted with permission from:
Zach T. multiple pregnancy.emedicine. Oct 2. 2007
HTN in Pregnancy
Hypertension is the most common medical problem encountered during pregnancy, complicating 2-3% of pregnancies.
HTN is classified into 4 categories
1) chronic hypertension,
3) preeclampsia superimposed on chronic hypertension
4) gestational hypertension (transient hypertension of pregnancy or chronic hypertension identified in the latter half of pregnancy).
blood pressure exceeding 140/90 mm Hg before pregnancy or before 20 weeks' gestation. It persists after 12 wks postpartum.
New-onset or worsening hypertension after 20 weeks' gestation should lead to a careful evaluation for manifestations of preeclampsia.
The diagnosis of severe hypertension or preeclampsia in the first or early second trimester necessitates exclusion of GTD and/or molar pregnancy.
Maternal Risk factors
Placental Risk factor
Gestational trophoblastic disease
Blood pressure should be measured in the sitting position, with the cuff at the level of the heart.
Women should be allowed to sit quietly for 5-10 minutes before each blood pressure measurement.
Korotkoff sounds I (the first sound) and V (the disappearance of sound) should be used to denote the systolic blood pressure (SBP) and DBP, respectively.
Indications of preg. termination Mild Severe Diastolic blood pressure <100mmhg 110 mmhg or higher Proteinuria Trace to 1+ Persistent 2+ or more Headache Absent present Visual disturbances Absent present Upper abdominal pain Absent Present Oliguria Absent Present Convulsion Absent Present Serum Cr Normal Elevated thrombocytopenia Absent Present Liver enzyme elevation Minimal Marked IUGR Absent Present Pulmonary edema Absent present
Platelet counts less than 100,000/µL suggest preeclampsia or ITP.
Hemoglobin levels greater than 13 g/dL suggest hemoconcentration.
Low Hbg levels may be due to microangiopathic hemolysis or iron deficiency.
Trace levels to +1 proteinuria are acceptable, but levels of +2 or greater are abnormal and should be quantified with a 24-hour urine collection or spot urine protein:creatinine ratio.
In a 24-hour urine collection, the reference range for protein excretion in pregnancy is up to 300 mg/d.
Creatinine clearance increases approximately 50% during pregnancy, and levels less than 100 mL/min suggest renal dysfunction that is either chronic or due to preeclampsia.
protein:Cr ratios appear to be more accurate than urinalysis, although an abnormal result should still be confirmed with a 24-hour urine collection.
PT/INR/aPTT results are abnormal,
thrombocytopenia is present,
the hemoglobin level is dropping
Alternate a biophysical profile with a fetal NST twice each week.
Ask for Serial fetal ultrasound starting at 18 weeks.
Methyldopa (Aldomet) Centrally acting antihypertensive agent widely considered the first-line agent for treatment of hypertension during pregnancy. 250 mg PO bid/tid; increase q2d prn; not to exceed 3 g/d
Hydralazine (Apresoline) Intravenous form is useful when treating severe hypertension due to preeclampsia/eclampsia. 10-20 mg/dose IV q4-6h prn initial; increase to 40 mg per dose prn BP >170/110 mm Hg: 0.1-0.2 mg/kg/dose IV q4-6h prn; not to exceed 20 mg or 1.7-3.5 mg/kg/d IV divided q4-6h
Life-threatening complications in preeclampsia
Acute renal failure
Hepatic infarction/rupture and subcapsular hematoma
if BP>160/110,blurred vision, head ache, epigastric pain, seizure then amp hydralazine 5 mg iv prn
MgSO4 (4 gr) in 200cc DW5% in 20 min then 10 gr(1/2) im in each buttock then 5 gr im q4h
If platelet is below 100000 then 20 gr in 1000cc infused in 100cc/hrs (check of I/O, RR, DTR, prep CPR set with 2 gr 20% MgSO4 ready) + Amp Dexa 6 mg bid for 4 doses
OTHER: Control of vital sign q15 min , control of FHR, fix foley,
Preterm labor is defined as the presence of uterine contractions of sufficient frequency and intensity to effect progressive effacement and dilation of the cervix prior to term gestation (between 20 and 37 wk).
It is the leading cause of neonatal mortality.
Causes of preterm Labor
decidual hemorrhage, (eg, abruption, mechanical factors such as uterine overdistension from multiple gestation or polyhydramnios),
2 drops /min, add 2 drops every 15 min if FHR and contractions are normal
Amp ampicillin 2gr iv qid +gentamicin im 80mg stat then 60 mg TDS
AMP clindamycin 900 mg iv TDS for allergic women to penicillin(continue antibiotics after delivery until the mother is a febrile
OTHER: Control of vital sign hourly
IMP:PLP before 37 weeks out patient: (contractions 4 in 20 min or 8 in 60 min +progressive change in cervix cervical dilation of more than one cervical effacement of more than 80 % or greater) if: Check of contractions:+ U/A, U/C: - Fern:- Then: Hydrate and sedate Stop of contractions: discharge With:isoxsuprine 10 mg TDS for 10 days Contractions persist: hospitalize Next slide
IMP:PLP before 37 weeks, hospitalized
Lab: CBC, BG, Rh, U/A, U/C, fern, reserve of 2 units of PC
1-1000cc Ringer free
2-MgSO4 (4 gr) in 200cc DW5% in 20 min then 20 gr in 1000cc infused in 100cc/hrs (check of I/O, RR,DTR, prep CPR set- I/O with measure)
3-Amp pethidine 25 mg iv 25 mg im
4-Amp ampicillin 2 gr IV qid
5-Amp erythromicin 400 mg QID
6- Amp betamethasone 12 mg im, repeat after 24 hrs for GA below 34 wks
OTHER: Control of vital sign q4hrs, Inform if LP, leakage, VB, ab VS or FHR
Contraindication for beta mimetics
Contraindication for MgSO4
Dosage of Ritodrine or Terbutaline for tocolysis
50-100 mcg/min increase by 50 mcg/min every 10 min
If labor is arrested continue the infusion for at least 12 hrs
250 mcg q3-4 hrs
Length of GA with multiple fetuses
Definition of postterm
Postterm pregnancies define pregnancies extending up to or after 42 weeks.
The reported frequency is 3-12%.
Cause of postterm P.
The most frequent cause of postterm pregnancy is inaccurate dating criteria
prior postterm pregnancy,
male gender of the fetus,
Risks of postterm P
Macrosomia complications like shoulder dystocia,
CPD and Maternal risks like an increase in labor dystocia, perineal injuries, and cesarean deliveries.
dysmaturity syndrome: affects 20% of postterm fetuses and is thought to be caused by chronic uteroplacental insufficiency resulting in oligohydramnios, meconium aspiration, and reversible neonatal complications.
NST and AFI 2 times per week for pregnancies continuing past 41 weeks.
Intra Uterine Growth Retardation
Intrauterine growth restriction (IUGR) occurs when the unborn baby is at or below the 10th weight percentile for his or her age (in weeks). The fetus is affected by a pathologic restriction in its ability to grow.
Low birth weight (LBW) means a baby with a birth weight of less than 2500Gms, which could be due to IUGR or Prematurity
Classification Symmetric l A symmetrical baby's brain is abnormally large when compared to the liver . may occur when the fetus experiences a problem during later development the baby's head and body are proportionately small . may occur when the fetus experiences a problem during early development.
Etiology of IUGR
Idiopathic- In a majority of cases (40%)
Maternal Risk Factors
Has had a previous baby with IUGR
Extremes of age
Small mothers (Ht & Wt)
poor weight gain and mal nutrition during preg.
Substance abuse (like tobacco,narcotics, alcohol)
low total blood volume during early pregnancy
Maternal Risk Factors
Living in High altitude locations
Drugs like anticoagulants, anticonvulsants
Cardio- vascular disease:preeclampsia , HTN, cyanotic heart disease, cardiac disease Gr III & IV, diabetic vascular lesions
present 3(I=24%) Mild-severe tetanic shock Fib<150 mg/dl death
Maternal HTN(44% of all cases)
Advanced maternal age
Short umbilical cord
Sudden decompression of the uterus (eg, PROM, delivery of first twin)
Idiopathic (probable abnormalities of uterine blood vessels and decidua)
Ultrasonography is not very useful in diagnosing placental abruption.
Retroplacental hematoma may be recognized in 2-25% of all abruptions.
Recognition of retroplacental hematoma depends on the degree of hematoma and on the operator's skill level.
IMP: R/O abruption
Prep 4 units of crossmatched packed red blood cells
Prep 5 units of platelets, prep 10 units of FFP
Continuous high-flow supplemental oxygen
One or 2 large-bore IV lines with normal saline (NS) or lactated Ringer (LR) solution+10 units of oxytocin in 1 lit of ringer start at 2 drops/min add 2 drops every 15 min if fetal heart rate and uterine contractions are favorable.
Closely observe the patient. Monitor vital signs and urine output, fetal heart rate and uterine height measurement.
Prepare OR for emergent C/S
(1) complete or total: the placenta covers 360° of the internal cervical os;
(2) incomplete or partial: 0°-360° of the internal cervical os is covered by placental tissue;
(3) marginal: the placental tissue does not cover the internal cervical os;
(4) low lying: the edge of the placenta lies abnormally close to but does not abut the internal cervical os.
prior placenta previa,
prior cesarean delivery,
increased maternal age,
large placentae (eg, multiple gestations or erythroblastosis),
maternal history of smoking.
1 in 200 deliveries
painless vaginal bleeding during the second half of pregnancy (70%).
It can occur without an inciting cause, although pelvic examination, intercourse, or labor may provoke it.
The average gestational age at presentation is 32 weeks.
Hemorrhage recurs, and, in nearly all cases, it is more severe the second time.
Patients are treated expectantly, with:
emergent cesarean delivery
Without endangering the life of the mother, all attempts are made to delay delivery until the fetal lungs mature.
Physical examination should be performed only with a fetus that has achieved pulmonary maturity and only in a fully staffed operating room.
TA sonography is the test of choice to confirm placenta previa.
When the internal cervical os cannot be visualized or when the results are inconclusive, transperineal or transvaginal sonography is recommended as an adjunct .
No increased risk of hemorrhage has been associated with transvaginal or transperineal sonography in this clinical setting.
Blood loss classifications
med-ed-online 2007 Class 1 Class 2 Class 3 Class 4 Blood Loss Volume (mls) in adult 750mls 800 - 1500mls 1500 - 2000mls >2000mls Blood Loss % Circ. blood volume <15% 15 - 30% 30 - 40% >40% Systolic Blood Pressure No change Normal Reduced Very low Diastolic Blood Pressure No change Raised Reduced Very low / Unrecordable Pulse (beats /min) Slight tachy- cardia 100 - 120 120 (thready) >120 (very thready) Capillary Refill Normal Slow (>2s) Slow (>2s) Undetectable Respiratory Rate Normal Normal Raised (>20/min) Raised (>20/min) Urine Flow (mls/hr) >30 20 - 30 10 - 20 0 - 10
med-ed-online 2007 Estimated blood loss Suitable fluid regimes 1000 mls 3000 mls crystalloid or 1000 mls colloid 1500 mls 1500 mls crystalloid & 1000mls colloid or 4500 mls crystalloid 2000 mls 1000 mls crystalloid, 1000mls colloid & 2 units blood or 3000 mls crystalloid & 2 units blood
Pictures and material of multiple pregnancy are adapted from:
Zach T. multiple pregnancy. emedicine. Oct 2. 2007
Dizygotic twins(fraternal) are produced when 2 sperm fertilize 2 ova. Separate amnions, chorions, and placentas are formed in dizygotic twins. The placentas in dizygotic twins may fuse if the implantation sites are proximate. The fused placentas can be easily separated after birth.
Monozygotic twins (Identical)develop when a single fertilized ovum splits during the first 2 weeks after conception. An early splitting (ie, within the first 2 d after fertilization-30%) of monozygotic twins produces separate chorions and amnions. These dichorionic twins have different placentas that can be separate or fused.
Later splitting (ie, 3-8 d after fertilization) results in monochorionic/diamniotic placentation .
Approximately 70% of monozygotic twins are monochorionic/diamniotic.
If splitting occurs even later (ie, during 9-12 d after fertilization), monochorionic/monoamniotic placentation occurs .
Monochorionic/monoamniotic twins are rare; only 1% of monozygotic twins have this form of placentation.
Monochorionic/monoamniotic twins have a common placenta with vascular communications between the 2 circulations.
Trizygotic triplets occur when 3 sperm fertilize 3 ova.
Dizygotic triplets develop from one set of monozygotic cotriplets and a third cotriplet derived from a different zygote.
Finally, 2 consecutive zygotic splittings with one split results in a vanished fetus and monozygotic triplets.
The birth rate of monozygotic twins is constant worldwide (approximately 4 per 1000 births).
Birth rates of dizygotic twins vary by race. (Highest in Africans and lowerest in Asians)
low birth weight infants( due to prematurity and (IUGR)
placenta previa, abruptio placenta,
group B streptococcal (GBS) infections,
hyaline membrane disease (HMD),
excessive weight gain,
sensation of more than one moving fetus
use of ovulation-inducing drugs
family history of dizygotic twins
Neonatal Lab Studies
CBC count: In TTTS, the donor twin is frequently anemic at birth. The recipient twin is polycythemic at birth.
Calcium level: Hypocalcemia is common in premature infants, especially the donor twin in TTTS.
Glucose level: Hypoglycemia is common in premature infants, especially if TTTS is present.
Bilirubin level: Hyperbilirubinemia due to TTTS may develop in polycythemic infants.
Twin reversed arterial perfusion (TRAP) sequence occurs when an acardiac twin receives all of the blood supply from the normal "pump" twin. This only occurs in monochorionic twins.
Occurs in monochorionic/monoamniotic or monochorionic/diamniotic twins. Vascular anastomoses in the monochorionic placenta result in transfusion of blood from one twin (ie, donor) to the other twin (ie, recipient). Polyhydramnios develops in the sac of the recipient twin and oligohydramnios develops in the sac of the donor twin.
Incomplete late division of monozygotic twins produces conjoined twins.
Thoracopagus - Joined at chest (40%)
Xiphopagus/omphalopagus - Joined at abdomen (34%)
Pygopagus - Joined at buttocks (18%)
Ischiopagus - Joined at ischium (6%)
Craniopagus - Joined at head (2%)
. Birth weight discrepancies of more than 20-25% are considered discordant. Discordant birth weights occur in 10% of twins.
Gestational Trophoblastic Neoplasia
hydatidiform mole : is the most common form of gestational trophoblastic neoplasia it can behave in a malignant or benign fashion,
invasive mole (chorioadenoma destruens),
and placental site trophoblastic tumor (PSTT).
In 80% of patients with a benign hydatidiform mole, serum HCG titers steadily drop to normal within 8-12 weeks after evacuation of the molar pregnancy.
In the other 20% of patients with a malignant hydatidiform mole, serum HCG titers either rise or plateau.
Stage I – Confined to the uterus
Stage II – Limited to the genital structures
Stage III – Lung metastases
Stage IV – Other metastases
WHO prognostic criteria1
Age 40 years or older = 1 point
Antecedent pregnancy terminated in abortion = 1 point
Antecedent full-term pregnancy = 2 points
Interval of 4 months to less than 7 months between antecedent pregnancy and start of chemotherapy = 1 point
Interval of 7-12 months between antecedent pregnancy and start of chemotherapy = 2 points
Interval of more than 12 months between antecedent pregnancy and start of chemotherapy = 4 points
WHO prognostic criteria 2
Beta-HCG level in serum is 1000 mIU/mL but less than 10,000 mIU/mL = 1 point
Beta-HCG level in serum is 10,000 mIU/mL but less than 100,000 mIU/mL = 2 points
Beta-HCG level in serum is 100,000 mIU/mL or greater = 4 points
Largest tumor is 3 cm but less than 5 cm = 1 point
Largest tumor is 5 cm or greater = 2 points
Site of metastases is spleen or kidney = 1 point
WHO prognostic criteria3
Site of metastases is gastrointestinal tract = 2 points
Site of metastases is brain or liver = 4 points
Number of metastases is 1-4 = 1 point
Number of metastases is 5-8 = 2 points
Number of metastases is more than 8 = 4 points
Prior chemotherapy with single drug = 2 points
Prior chemotherapy with multiple drugs = 4 points
Sign and Symptoms
Patients with a hydatidiform mole present with signs and symptoms of pregnancy.
The most frequent symptom of gestational trophoblastic neoplasia (GTN) is abnormal uterine bleeding.
Patients have a history of amenorrhea. Occasionally, the typical hydatid vesicles (edematous villi) are passed through the vagina.
Sign and Symptoms
Prolonged hyperemesis gravidarum
signs and symptoms associated with the metastatic disease, such as hematuria, hemoptysis, abdominal pain, and neurologic symptoms
a positive pregnancy test result occurs in the absence of a fetus.
vesicles in the vagina is diagnostic
Enlarged ovaries secondary to theca lutein cysts are found in up to 20% of cases.
The cysts regress after evacuation of the hydatidiform mole for 12 weeks.
A hydatidiform mole occurs when a haploid sperm fertilizes an egg that has no maternal chromosomes and then duplicates its chromosomal complement.
Most complete hydatidiform moles are 46,XX, and all the chromosomes come from the male.
Of hydatidiform moles, 10-15% are 46,XY. This occurs when 2 sperm, 1 carrying an X and the other carrying a Y, fertilize an "empty" egg.
Partial moles are 69,XXY, and 2 sets of chromosomes are of paternal origin.
Emergency department care involves :
starting intravenous (IV) fluids (crystalloids)
sending blood for type and antibody screen
Rh-negative patients should receive anti–RhD immune globulin, such as RhoGAM, if not already immunized
Patients with benign do not require medical therapy.
observing patients with weekly serum HCG titers.
Only patients with rising or plateauing titers should be treated with chemotherapy.
Patients with malignant nonmetastatic or metastatic low-risk GTN are treated with single-agent chemotherapy like MTX or actinomycin D in patients with poor liver function
During treatment, the serum HCG titers are monitored every week.
One additional course of chemotherapy is administered after a normal serum HCG titer.
After 3-4 normal serum HCG titers, the titers are followed once per month for 1 year.
A switch from MTX to actinomycin D is made if the patient receiving MTX for nonmetastatic or metastatic low-risk GTN develops rising or plateauing serum HCG titers.
Patients with high-risk metastatic are subdivided into 2 groups:
In patients with a WHO score of less than 8, a combination of MTX, actinomycin D, and cyclophosphamide can be used. This is known as the MAC regimen. This chemotherapeutic regimen is administered every 19-21 days (from day 1 of the previous chemotherapy cycle) until the serum HCG titers normalize.
Patients with WHO scores of 8 or higher are treated with a combination of etoposide, MTX, and actinomycin D administered in the first week of a 2-week cycle and cyclophosphamide and vincristine (Oncovin) administered in the second week. This is known as the EMA-CO regimen. Two additional courses of EMA-CO or EMA-CE are administered after a normal serum HCG titer in very high-risk patients.
Patients with metastasis to the brain receive whole brain irradiation (3000 cGy) in combination with chemotherapy. Corticosteroids (Decadron) with systemic effect are administered to reduce brain edema.
Patients with liver metastasis are considered for liver irradiation (2000 cGy).
The treatment of a hydatidiform mole is evacuation of the uterus by suction and sharp curettage.
To avoid excessive bleeding, oxytocin is administered intravenously at the initiation of the suctioning of the uterine contents.
The largest possible suction curet is used, usually a 10F or 12F.
Obtain follow-up serum HCG titers :
once per week until 3-4 normal values are obtained.
Then, obtain them once per month for 6 months.
Have patients use reliable contraception, such as oral contraceptives or depot progesterone injections, during the period of follow-up care.
Nonmetastatic GTN has a cure rate with chemotherapy of close to 100%.
Metastatic low-risk gestational trophoblastic neoplasia has a cure rate with chemotherapy of close to 100%.
Metastatic high-risk gestational trophoblastic neoplasia has a cure rate with chemotherapy of approximately 75%.
After 12 months of normal HCG titers, less than 1% of patients with malignant gestational trophoblastic neoplasia have recurrences.
The rate of occurrence of a repeat molar pregnancy is approximately 1-2%.
The rate of occurrence of a repeat molar pregnancy in a patient with a history of 2 previous hydatidiform moles is approximately 10-20%.
The pregnancy rate after chemotherapy with MTX and cyclophosphamide is 80%. Of women treated with EMA-CO, 46% have had at least 1 live birth after chemotherapy.
Patients who become pregnant after treatment for GTN should have a pelvic ultrasound early during the pregnancy to confirm that the pregnancy is normal.
ADAPTATION TO PREGNANCY
In early pregnancy Estrogen and Progesterone stimulate beta cell hyperplasia and increased insulin secretion
Glycogenolyis and peripheral utilization increase
The net result is relative hypoglycemia
GLUCOSE LEVELS IN NORMAL PREGNANCY
Fasting levels decline by 10 – 11 mg/dl
Postprandial levels rarely exceed 120-140 mg/dl
Glucose excursions with meals 30 – 35 mg/dl
Marked increase in insulin levels with feeding
CHO METABOLISM 20- 24 WEEKS
Increased human placental lactogen – diabetogenic
Increased prolactin – insulin resistance
Increased cortisol – decreased glycogen storage
OTHER METABOLIC CHANGES
Stable amounts of FFA
Increased cholesterol and TG
Reduced amino acid levels
Remains the leading cause of blindness in women ages 24-64
Every patient with pre-gestational diabetes should have a retinal examination in early pregnancy
Laser therapy is safe and effective during pregnancy
Has a variable course during pregnancy
Accounts for 1/3 of the deaths in diabetics < 31
Renal findings are present as early as 1-2 years after diagnosis
Creatinine clearance may improve in pregnancy due to increased renal blood flow
Proteinuria may increase substantially
CHRONIC RENAL FAILURE
Pregnancy is possible even in patients requiring hemodialysis
Reliable contraception is advised
Fertility and successful pregnancy outcomes are reduced with serum Cr > 2.0
Should be aggressively controlled
ACE inhibitors are contraindicated
Calcium channel blockers are probably a reasonable alternative and are safe during pregnancy
Increases the incidence of fetal growth restriction and superimposed preeclampsia
BP > 140/90
Proteinuria > 300 mg/24 hours or increase in baseline
May be difficult to diagnose in the presence of renal disease and chronic HTN