Arab Board Ob/Gyn Part 1 cheat sheet

Uterine artery arises from the internal iliac artery and crosses above the ureter about 2 cm lateral to the cervix ('water under the bridge'); it anastomoses with the ovarian artery.

Normal ovulatory cycle: the LH surge occurs about 24-36 hours before ovulation; the luteal phase is relatively constant at about 14 days, so cycle length variation is mainly follicular.

Mullerian ducts form the fallopian tubes, uterus, cervix, and upper vagina; failed fusion or septal resorption causes bicornuate, septate, or didelphys uteri.

Pregnancy pharmacokinetics: plasma volume rises 40-50%, glomerular filtration rate rises about 50%, and hepatic CYP activity changes; renally cleared drugs often need dose adjustment.

hCG peaks at about 8-10 weeks of gestation; it maintains the corpus luteum and progesterone production until the placenta takes over around 8-10 weeks.

Autosomal recessive disease: 25% recurrence risk for carrier parents; autosomal dominant: 50%; X-linked recessive: 50% of sons affected when the mother is a carrier.

Bacterial vaginosis is a polymicrobial overgrowth of Gardnerella vaginalis and anaerobes, not a classic sexually transmitted infection; clue cells and pH >4.5 support diagnosis.

The ureter passes under the uterine artery and about 1.5-2 cm lateral to the cervix; this relationship explains ureteral injury risk at hysterectomy and cesarean hysterectomy.

Normal pregnancy is hypercoagulable: fibrinogen and clotting factors rise, protein S falls, and venous thromboembolism risk is highest postpartum.

Naegele rule: estimated due date = first day of last menstrual period + 280 days; adjust by adding (cycle length - 28) days if cycles are longer or shorter.

Nulliparous antenatal schedule example: every 4 weeks to 28 weeks, every 2 weeks to 36 weeks, then weekly until delivery; modify for risk factors.

Fetal heart rate baseline is 110-160 beats/min; moderate variability is 6-25 beats/min; accelerations are >=15 beats/min for >=15 seconds after 32 weeks.

First stage of labor ends at full cervical dilatation; second stage ends at delivery; third stage ends with placental expulsion.

Active phase arrest: cervical dilatation >=6 cm with ruptured membranes and no change for >=4 hours with adequate contractions or >=6 hours with inadequate contractions.

Oxytocin tachysystole is more than 5 contractions in 10 minutes averaged over 30 minutes; reduce or stop oxytocin and consider tocolysis if fetal intolerance.

Group B streptococcus prophylaxis: penicillin G 5 million units IV loading, then 2.5-3 million units every 4 hours; use clindamycin only if susceptibility is known.

Postpartum hemorrhage: uterine atony is the most common cause; assess tone, trauma, tissue, and thrombin; give tranexamic acid within 3 hours of birth.

Shoulder dystocia maneuvers: McRoberts position and suprapubic pressure first; avoid fundal pressure; consider internal rotational maneuvers and episiotomy if needed.

Fetal growth restriction: estimated fetal weight <10th centile; umbilical artery Doppler and fetal surveillance guide timing of delivery, especially before 37 weeks.

Preeclampsia: new hypertension after 20 weeks plus proteinuria or end-organ dysfunction; severe features include blood pressure >=160/110, platelets <100,000, or renal, liver, neurologic, or pulmonary involvement.

Severe preeclampsia magnesium sulfate: 4-6 g IV loading over 15-20 minutes, then 1-2 g/hour; monitor deep tendon reflexes, respiratory rate, and urine output.

Gestational diabetes 75-g OGTT thresholds: fasting >=92, 1-hour >=180, 2-hour >=153 mg/dL; one abnormal value is diagnostic under IADPSG criteria.

Preterm labor before 34 weeks: antenatal corticosteroids reduce neonatal respiratory distress, intraventricular hemorrhage, and mortality; give magnesium sulfate for neuroprotection before 32 weeks.

RhD alloimmunization prevention: anti-D immune globulin at about 28 weeks and within 72 hours postpartum for RhD-negative unsensitized women with RhD-positive or unknown infants.

Oligohydramnios: amniotic fluid index <5 cm or deepest vertical pocket <2 cm; polyhydramnios: AFI >24 cm or deepest pocket >8 cm.

Monochorionic twins share a placenta; twin-twin transfusion syndrome presents with discordant amniotic fluid; laser ablation is treatment for severe cases before 26 weeks.

Diabetic ketoacidosis in pregnancy can occur at lower glucose levels than outside pregnancy; treat with IV fluids, insulin infusion, potassium replacement, and precipitant search.

Cardiac disease is a leading indirect cause of maternal death; peripartum cardiomyopathy presents with heart failure and ejection fraction <45% late pregnancy to 5 months postpartum.

Hypothyroidism in pregnancy: levothyroxine requirement often rises 20-30%; check TSH each trimester; untreated hypothyroidism increases miscarriage and neurodevelopmental risk.

Epilepsy in pregnancy: valproate carries the highest teratogenic risk; lamotrigine levels fall substantially in pregnancy; folic acid supplementation is recommended preconceptionally.

Venous thromboembolism: low-molecular-weight heparin is preferred in pregnancy; warfarin is contraindicated because of embryopathy; continue anticoagulation postpartum for at least 6 weeks.

Sepsis in pregnancy: give broad-spectrum antibiotics within 1 hour of recognition, obtain cultures, and perform source control; physiological changes can delay signs.

Ectopic pregnancy: methotrexate is an option if hemodynamically stable, unruptured, hCG <5,000 IU/L, mass <3.5 cm, and no fetal cardiac activity.

Placenta accreta spectrum: risk is highest with placenta previa and prior cesarean; planned delivery by an experienced team with hysterectomy capability reduces hemorrhage.

Amniotic fluid embolism: sudden hypotension, hypoxia, and coagulopathy during labor or postpartum; management is supportive with airway, circulation, and blood product replacement.

Polycystic ovary syndrome Rotterdam criteria: two of three: oligo/anovulation, clinical or biochemical hyperandrogenism, and polycystic ovarian morphology on ultrasound.

Pelvic inflammatory disease minimum criteria: pelvic or lower abdominal pain plus cervical motion, uterine, or adnexal tenderness; treat empirically with ceftriaxone, doxycycline, and metronidazole.

Bacterial vaginosis Amsel criteria: homogeneous discharge, pH >4.5, clue cells, positive whiff test; three of four are required for diagnosis.

Vulvovaginal candidiasis: thick white discharge, itching, and vulvar erythema; treat with topical azole or a single oral fluconazole dose in uncomplicated cases.

Endometriosis: ectopic endometrial glands and stroma; laparoscopy is the diagnostic gold standard; GnRH agonists, progestins, and combined hormonal contraceptives reduce pain.

Uterine leiomyomas are benign smooth muscle tumors; symptoms include heavy bleeding, bulk symptoms, and infertility; treatment options include NSAIDs, hormonal therapy, myomectomy, and embolization.

Abnormal uterine bleeding PALM-COEIN: Polyp, Adenomyosis, Leiomyoma, Malignancy/hyperplasia; Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, Not otherwise classified.

Cervical cancer screening: HPV primary testing or cytology; colposcopy for abnormal results; vaccination against HPV reduces cervical intraepithelial neoplasia.

Ovarian torsion: sudden unilateral pelvic pain with nausea; Doppler flow may be normal; urgent laparoscopy is required to preserve ovarian function.

Cervical cancer: almost all cases are linked to high-risk HPV, especially types 16 and 18; staging is clinical/FIGO; early disease is treated with surgery or radiation.

Endometrial cancer is the most common gynecologic malignancy; risk factors include obesity, unopposed estrogen, diabetes, nulliparity, and Lynch syndrome; postmenopausal bleeding is the classic presentation.

Ovarian cancer: CA125 lacks screening specificity; BRCA1/2 mutations increase risk; treatment is cytoreductive surgery plus platinum-based chemotherapy.

Breast cancer: most common cancer in women; receptor status (ER, PR, HER2) guides therapy; tamoxifen is used for ER-positive disease and risk reduction.

Gestational trophoblastic neoplasia: persistent or rising hCG after molar pregnancy; methotrexate for low-risk disease; EMA-CO for high-risk disease.

Vulvar cancer: often HPV-related or associated with lichen sclerosus; diagnosis requires biopsy; treatment is radical local excision with groin node assessment.

Ovarian germ cell tumors: common in young women; tumor markers include AFP and hCG; fertility-sparing surgery is often possible.

Infertility is failure to conceive after 12 months of regular unprotected intercourse; earlier evaluation at age >=35 or with irregular cycles, known pathology, or male risk factors.

Letrozole is first-line ovulation induction in polycystic ovary syndrome; it is an aromatase inhibitor and often yields higher live birth rates than clomiphene.

Copper intrauterine device is the most effective emergency contraception when inserted within 5 days of unprotected intercourse; it also provides long-term contraception.

Combined oral contraceptives prevent ovulation by suppressing gonadotropins; efficacy depends on adherence; estrogen-containing products increase venous thromboembolism risk.

Primary amenorrhea: no menses by age 15 with normal secondary sexual characteristics or by 13 without them; evaluate for gonadal dysgenesis, outflow obstruction, and hypogonadotropic causes.

Menopause is 12 months of amenorrhea after the final menses; FSH is typically >30 IU/L; hormone therapy with estrogen plus progestin is used in women with a uterus.

WHO amenorrhea classification: group I hypothalamic-pituitary failure, group II eugonadotropic (PCOS), group III hypergonadotropic (ovarian failure), group IV outflow tract.

Pelvic organ prolapse quantification (POP-Q): stage 0 no prolapse; stage 1 leading edge >-1 cm; stage 2 between -1 and +1 cm; stage 3 >+1 to +2 cm; stage 4 complete eversion.

Stress urinary incontinence is involuntary urine loss with cough, sneeze, or exertion; first-line treatment is pelvic floor muscle training; midurethral sling is a surgical option.

Overactive bladder: urgency, frequency, and urge incontinence; behavioral therapy first; antimuscarinics or beta-3 agonists second; refractory cases may receive botulinum toxin or neuromodulation.

Urodynamic stress incontinence is demonstrated by involuntary urine leakage during filling cystometry with increased abdominal pressure, without detrusor contraction.

Pelvic floor muscle training: supervised program for at least 3 months; improves stress and mixed incontinence; biofeedback may improve technique.

Vesicovaginal fistula: continuous urinary leakage after pelvic surgery or obstructed labor; diagnosis with speculum and dye test; surgical repair after tissue healing.

Sensitivity = TP/(TP+FN); specificity = TN/(TN+FP); positive predictive value depends on prevalence: PPV = TP/(TP+FP).

Number needed to treat = 1/absolute risk reduction; number needed to harm = 1/absolute risk increase.

Randomized controlled trial: random allocation, allocation concealment, and blinding reduce selection and information bias; intention-to-treat analysis preserves randomization.

p-value: probability of observing a result as extreme or more extreme if the null hypothesis is true; alpha 0.05 means a 5% type I error rate.

Power = 1 - beta; conventional power is 80%; increasing sample size, effect size, or reducing variability increases power.

95% confidence interval: if repeated many times, 95% of such intervals would contain the true parameter; it reflects precision and is not a probability statement about the parameter.

Levels of evidence: systematic reviews of randomized trials are highest; then randomized trials, cohort studies, case-control studies, case series, and expert opinion.

Bias types: selection bias, information bias, confounding; randomization and multivariable adjustment address confounding.

Informed consent requires disclosure of diagnosis, proposed treatment, alternatives, risks and benefits, and consequences of refusal; the patient must have capacity and voluntariness.

Confidentiality exceptions include patient consent, legal requirement, serious public health risk, and prevention of serious harm; disclose only the minimum necessary information.

Research ethics: institutional review board approval, informed consent, minimization of harm, and equitable selection of participants are core requirements.

Error disclosure: after a harmful error, promptly inform the patient, explain what happened, apologize, and describe prevention steps; document the discussion.

WHO surgical safety checklist has three phases: sign-in before induction, time-out before incision, and sign-out before leaving the operating room.

Hand hygiene is the single most effective infection prevention measure; use alcohol-based rub or soap and water at WHO's five moments.

Never events are clearly identifiable, preventable serious adverse events such as wrong-site surgery or retained surgical items; reporting supports system improvement.

Conflict of interest: financial or personal interests that could influence judgment; disclose and manage, and recuse from decisions when appropriate.