Summary
Highlights
The lecturer begins the session welcoming viewers and performing an audio check before continuing the OB lecture. The session will cover intrapartal OB, labor and delivery, some postpartum aspects, and abnormal OB. The first topic is the passageway, referring to the birth canal, which includes the bony pelvis, cervix, pelvic floor, vagina, and vaginal opening. Four types of pelvis are discussed: Gynecoid (most common and ideal for vaginal delivery), Anthropoid (oval, allows vaginal delivery in occiput posterior position), Android (male pelvis, heart-shaped, difficult for vaginal delivery), and Platipeloid (kidney-bean shaped, rarest type). The importance of interspinous diameter (over 10.5 cm) for preventing cephalopelvic disproportion is highlighted, along with other pelvic diameter measurements like diagonal conjugate (12.5 cm) and true conjugate (11 cm).
The discussion moves to the 'power' of labor, which involves uterine contractions. Primary power is involuntary, triggered by oxytocin release (Ferguson reflex). Nurses and midwives must monitor contraction parameters: increment (increasing force), duration (beginning to end of one contraction), intensity (strength: mild, moderate, strong, likened to nose, chin, forehead), acme (peak of contraction, lowest fetal heart tone), decrement (decreasing force), interval (end of one contraction to beginning of next), and frequency (beginning of one contraction to beginning of next). True labor is characterized by regular, rhythmic, increasing frequency and duration, and decreasing interval, alongside cervical changes. False labor contractions are sporadic, painless, confined to the abdomen, and relieved by rest or medication. The hallmark of true labor is cervical effacement and dilatation.
The four stages of labor are detailed. The first stage, or cervical dilatation/preparatory stage, is the longest and most difficult, starting with true labor onset and ending with full cervical dilatation (10 cm). Progressive labor involves 1.0-1.25 cm/hour dilatation for primigravida and 1.5 cm/hour for multipara. The first stage has three phases: latent (0-3 cm, mild contractions), active (4-7 cm, moderate contractions), and transitional (8-10 cm, strong contractions). In this stage, patients should be encouraged to walk and stay upright to facilitate fetal descent, but not push. The second stage, fetal expulsion, begins with full dilatation and ends with the baby's birth. Crowning signals this stage. Rapid, panting breathing is encouraged, and the Regens maneuver (coxigeal pressure) is applied for head support and to prevent lacerations. The seven cardinal movements of labor are detailed: engagement, descent, flexion, internal rotation, extension, external rotation, and expulsion. Immediate newborn care, including drying, skin-to-skin contact, cord clamping (2cm, 5cm, cut close to first clamp), and oxytocin administration (10 units to mother), is emphasized. The third stage, placental expulsion, starts after fetal delivery and ends with placental delivery (usually within 30 minutes). Signs of placental separation (Calkin’s sign, sudden gush of blood, lengthening of cord – most reliable) are critical. The Shultz mechanism (shiny side first) is the ideal delivery method. Fundal massage and oxytocin are used to ensure uterine contraction and prevent hemorrhage. The fourth stage, recovery or immediate postpartum (first 1-2 hours), is the most dangerous due to the risk of postpartum hemorrhage. Monitoring for uterine atony (soft, boggy uterus, necessitating massage and uterotonics like oxytocin) and vital signs is crucial. A slight temperature elevation (up to 38°C) due to exhaustion/dehydration is normal, but higher temperatures or abnormal heart/respiratory rates indicate infection or shock.
Key postpartum assessments include monitoring vital signs (every 15 minutes for the first hour, then every 30 minutes for the second hour), checking lochia discharge, and assessing uterine involution. Involution, the return of the uterus to its non-pregnant state, takes about 6 weeks. The fundus should be firm, midline, and at or below the umbilicus after delivery. Deviation suggests a full bladder, requiring assistance to void, not immediate catheterization. Postpartum hemorrhage is suspected with blood loss >500ml for vaginal delivery or >1000ml for CS, or saturating a pad in <15 minutes. 'After pains' (intermittent uterine contractions in the first 2-3 days postpartum) are normal, especially in breastfeeding and multiparous women, aiding involution. Sudden gushes of blood when rising are normal due to blood pooling. Postpartum blues (sadness, mood swings, crying, difficulty sleeping) are normal, peaking around day 5 and resolving within 7-14 days; prolonged symptoms may indicate depression. Reva Rubin's maternal adaptation phases are discussed: taking-in (passive, dependent, focus on self-needs, first 2 days), taking-hold (dependent-independent, increased interest in infant care, 2-7 days), and letting-go (full independence, adapts to parenthood, acceptance of baby's real image, 7 days onwards).
Maternal death is defined as death during pregnancy or within 42 days of termination. It can be direct (related to pregnancy/birth, e.g., hemorrhage, obstructed labor, unsafe abortion, sepsis, eclampsia), indirect (due to pre-existing conditions exacerbated by pregnancy, e.g., cardiac disease), or coincidental (unrelated to pregnancy, e.g., accidents). Hemorrhage is the leading cause of maternal mortality worldwide. Postpartum hemorrhage is classified as early (within 24 hours, often due to uterine atony) or late (24 hours to 6 weeks, often due to retained placental fragments). The 4 Ts (Tone, Trauma, Tissue, Thrombin) are factors contributing to postpartum hemorrhage. Uterine atony (tone problem) is common with overdistended uterus (macrosomia, polyhydramnios, multiple pregnancy) or use of certain drugs (anesthesia, magnesium sulfate). Trauma involves lacerations or uterine inversion. Tissue refers to retained placental fragments. Thrombin indicates coagulation disorders.
Bleeding disorders are categorized by trimester. First trimester causes include abortion and ectopic pregnancy. Abortion is the termination of pregnancy before 20 weeks or fetal weight <500g, often caused by chromosomal abnormalities. Risk factors include misoprostol/mifepristone use, illicit drug use (cocaine), smoking, stress, advanced maternal/paternal age, reproductive tract abnormalities, reduced progesterone, infections (chlamydia, gonorrhea, listeria), and diabetes mellitus. Different types of abortion are detailed: Threatened (mild pain, spotting, closed cervix), Inevitable (moderate to severe pain, profuse bleeding, open cervix, ruptured membranes), Complete (all products expelled, pain/bleeding abates, cervix may close), Incomplete (some products retained, severe pain, profuse bleeding, open cervix, requires D&C), Missed (fetal death but not expelled, often asymptomatic, confirmed by absent FHT and ultrasound, requires D&C), Septic (abortion with infection, requires D&C and antibiotics), and Habitual (three or more consecutive losses, often due to incompetent cervix, managed with cerclage). Ectopic pregnancy (implantation outside the uterus, most commonly in the fallopian tube's ampulla) is another cause of first-trimester bleeding. Risk factors include smoking, adhesions, tumors/scars in the fallopian tube (often from PID caused by chlamydia or gonorrhea), IUD use, and a history of ectopic pregnancy. Signs include unilateral lower quadrant pain, palpable adnexal mass, and spotting. Rupture is indicated by severe, sharp, knife-like pain radiating to the shoulder or neck, and Cullen's sign (bluish discoloration around the navel indicating internal bleeding). Management involves pain relief, methotrexate for unruptured cases, or surgery (salpingostomy/salpingectomy) for ruptured tubes. Priority is given to the mother's life.
Second-trimester bleeding can be caused by H mall (hydatidiform mole) or incompetent cervix. H mall is a gestational trophoblastic disease where the chorion fails to become a placenta, forming a clear vesicular mass instead. Risk factors include multiparity, advanced maternal age, malnutrition, low socioeconomic status, and Asian ethnicity. Signs of H mall include abnormally high HCG levels, hyperemesis gravidarum, larger-than-normal uterus without fetal heart tones, signs of preeclampsia before 20 weeks, and hyperthyroidism. The hallmark sign is brown vaginal bleeding with grape-like or sago-like discharges. Diagnosis is by ultrasound showing a snowstorm appearance. Treatment involves methotrexate to prevent choriocarcinoma (a dreaded complication) and suction aspiration/curettage to evacuate the molar pregnancy. For older patients at high risk for cancer, a hysterectomy (TABSO) might be recommended. Post-treatment, HCG levels are monitored for one year to detect residual disease or cancer, and contraception is advised for at least one year. The most common site of choriocarcinoma metastasis is the lungs, requiring regular chest X-rays. Finally, blood transfusion guidelines for managing hemorrhage are briefly covered: 18 or 19 gauge needles are ideal, PRBCs administered over 4 hours, and 0.9% sodium chloride as the compatible isotonic solution. Informed consent and checking patient religion (e.g., Jehovah’s Witnesses refuse blood) are crucial. Double verification of blood products and close vital sign monitoring (before, during, and every 15 minutes for the first 15 minutes of infusion) are essential. The first action for a transfusion reaction is to stop the infusion.