OBGYN Lecture Notes Flashcards
What are some of the ways of estimating birth weight? (3)
- USG: by measuring head and abdominal circumference, and femoral bone length
- By using the estimated birth date
- By measuring Crown-to-rump length (SF: Symphisis-Fundus length) within the first trimester (doesn’t work in the others)
How is the baby usually delivered in according to cardinal movements during vaginal delivery?
With head first, then the anterior shoulder (mother’s anterior) right after that if the baby lies on it’s side
What is shoulder dystocia?
A life-threating emergency where the head is already out, but anterior shoulder of the baby is stuck behind the the pubic symphysis during delivery and there is need for additional obstetric maneuvers for delivery.
Fetal complications of shoulder dystocia?(4)
Fetal:
- Erb’s palsy: cause the head is out and the shoulder is stuck, there will be streching and injury to the brachial plexus. (most typical complication)
- Phrenic nerve palsy (remember where it’s located)
- Fracture of humerus and clavicle
- Hypoxic brain injury and death (due to compression on neck and umbilical cord)
Maternal complications of shoulder dystocia?(3)
- Laceration and uterine rupture
- Postpartum hemorrhage
- Symphysis Pubis Dysfunction (pelvic discomfort)
Signs of shoulder dystocia? (2)
- Turtle sign: fetal head retracts into the perineum right after expulsion
- Head-to-body expulsion time > 60 seconds
10 Risk facors for shoulder dystocia?
Remember, 50% of cases are idiopathic though!
- Fetal Macrosomia (when EFW > 4500g)
- Tumors
- Malformations
- DM in mother (babies have often macrosomia or different shoulder-to-head ratio than normal)
- Operative vaginal delivery (where forceps or vacuum often are used)
- Previous history of shoulder dystocia babies
- Postterm pregnancy
- Male fetal gender (males have brouder shoulders than females)
- Obese (BMI>30) or high gestational weight (>20kg) of mother
- Advanced maternal age (>40yerars)
What’s the goal when managing shoulder dystocia and what do?
The goal is to deliver the infant before asphyxia occurs, you have 5 mins!
You can try to do the following:
- Put mother in dorsal lithiotomy position and tell her NOT to push (might compress the umbilical cord)
- Avoid any excessive neck rotation of the baby
- Drain the bladder and see if it helps
- Do episiotomy or one of the shoulder dystocia maneuvers
What’s an Episiotomy?
An incision made in the perineum (the tissue between the vaginal opening and the anus during childbirth)
Name the maneuvers you can try during delivery of child with shoulder dystocia, from best to worst (9)
Chronological order from bets to worst:
- Mcroberts Maneuver: two people grab each leg of the mather and sharply flex the thigh back against the abdomen (50% effective)
- Suprapubic pressure: Fist on pubic symphysis at an oblique angle to dislodge the anterior shoulder (often done at the same time as McRoberts)
- Delivery of posterior arm and shoulder first, by directly placing hand into vagina and locating
- Rubin Maneuver: pressure on anterior shoulder while rotating infant
- Woods Corckskrew Maneuver: pressure on posterior shoulder while rotating
- Gaskin all-fours: mother stands on all-four and tries to deliver
- Clavicular fracture
- Zavanelli Maneuver: One of the last resorts. Head is pushed back into uterus and emergency c-section is done
- Symphysiotomy: Very last resort if nothing else works. Incision of pubic symphysis
How many obligatory USGs are done during pregnancy and when are they done?
2 obligatory ultrasounds:
- First trimester: week 11-14 scan (chromosomal abnormalities)
- Second trimester: week 18-22 ( prenatal testing),
Some countries have a 3rd scan in third trimester week 28-30 in some countries (signs of hypertrophy and other pathology)
What is a fetal station?
The fetal station is a measurement of how far the baby has descended in the pelvis, measured by the relationship of the fetal head to the ischial spines (sit bones). The ischial spines are approximately 3 to 4 centimeters inside the vagina and are used as the reference point for the station score.
Explain the fetal station numbers
The ischial spines are approximately 3 to 4 centimeters inside the vagina and are used as the reference point for the station score. Fetal station is stated in negative and positive numbers with 1cm between each number.
- -5 station is a floating baby
- -3 station is when the head is above the pelvis
- 0 station is when the head is at the bottom of the pelvis, also known as being fully engaged
- +3 station is beginning to emerge from the birth canal
- +5 station is crowning
Causes for increasing incidence spontanous abortions these days? (3)
- More IVF (In Vitro Fertilization) these days
- Older women get babies these days
- Environmental reasons???
2 instruments commonly used to assist in vaginal delivery?
- Forceps
- Vacuum extractor
4 Types of forceps procedyre?
- Outlet forceps (best option)
- Low forceps. (more complicated)
- Midforceps
- High forceps
3 indications for Forceps delivery?
- Poor maternal labor in 2nd phase of labor
- Maternal distress
- Fetal distress (CTG)
Conditions necessary for forceps delivery? (8)
- Cervix must be fully dilated
- Ruptured membranes
- Engaged head
- Head of fetus is least at +2 station
- Absolute knowledge of fetal position
- No evidence of CPD (cephalopelvic disproportion)
- Adequate anesthesia
- Empty bladder
What’s important to remember when placing the cup of a vacuum extractor? (2)
- It should be placed over the posterior fontanelle! (head will be abnormally formed if you put it anywhere else)
- After placement, take a finger around the cup and be sure that no vaginal wall is in the cup (otherwise may cause vaginal laceration)
Indications for using vacuum extractor during vaginal delivery?
- Fetal distress in 2nd phase
- Dilatation >7 cm
- Prolapsed cord (when cord comes out of uterus before baby)
- Twin birth were there’s problems of delivering 2nd twin
- Maternal indications: physical distress, to avoid maternal effort in patient with hypertension, cardiac and respiratory disease
2 Contraindications of Vacuum extractor?
- Malpresentation (baby is not in the right position for it)
- Cuagulopathy (intracranial hemorrhage or cephalohematoma)
Complications from using Vacuum extractor? (3)
- Scalp laceration
- Cephalohematoma
- Subgaleal hemorrhage (rupture of emissary veins between dura, sinuses and scalp)
B-hCG: what is normal (no pregancy), what lvl causes a pausitive pregnancy test? When does it peak?
- Negative pregancy test: B-hCG < 5
- Positive pregancy test: B-hCG > 25 (may already show 8-9 days after ovulation)
- Peaks between week 8 - 12
What does a B-hCG > 1500 indicate?
At that level, you should be able to see a gestational sac in the uerus on USG. If you can’t see it, think about ectopic pregnancy.
Definition of miscarriage?
Expulsion of fetus either <500g in weight or <22 weeks old
In what period is the fetus considered viable during the pregnancy?
Varies between week 24 - 28
Percentage of normal pregnancies ending in miscarriage?
10 - 15%
Percentage of EARLY pregnancies ending in miscarriage?
45 - 55%
What is a Biochemical pregnancy and what is it caused by?
B-hCG positive pregnancy where embryo implants in the uterus but never takes hold ending in a miscarriage (which is why you should wait with a pregnancy test until 1st missed menstruation)
Within what period of trying do most fertile couples get pregnant?
Most couples get pregnant within 6 months of trying
How long should a couple try to get pregnant before we start to suspect infertility?
>,1year of trying, suspect infertility
In which week of pregnancy should you be able to see the heartbeat of the fetus on USG?
At around week 6
Name the different classifications of misscarriages (6)
- Threatened miscarriage
- Inevitable miscarriage
- Incomplete miscarriage
- Complete miscarriage
- Missed miscarriage
- Septic miscarriage
Threatened miscarriage: How does it present and what can we do about it?
- Presents as a vaginal bleeding with lower abdominal pain, and closed cervical os on examination.
- Do a USG, if fetal cardiac activity is present, put her on high dose progesterone and follow.up in a week (though 1/3 of women progress to inevitable miscarriage)
Inevitable miscarriage: How does it present and what can we do about it?
- Presents as lower abdominal pain with heavy bleeding and an open cervical os
- Need to quickly hospitalize and give analgesia
Incomplete miscarriage: How does it present (3) and how is it managed?
Presents as:
- Always > 8 week
- History of blood with fleshy masses (bleeding may cause shock)
- History of pain
Managed by Curettage
What is Curettage?
Is the use of a curette (a scoop) to remove tissue by scraping or scooping. Used after a miscarriage to remove remaining tissue.
Complications of a courettage procedure? (4)
- Uterus perforation
- Asherman’s syndrome (adhesions of the uterus)
- Lack of menstruation
- Infertility
Complete miscarriage: How does it present? (5) Management?
- Occurs within the first 6-8 weeks
- History of passage of products followed by stop in pain and bleeding
- Closed cervical os
- Small uterine size
- On its own symptoms of pregnancy start to dissappear and tests become negative
Always do USG to double check!
What’s a Missed miscarriage and how does it present?
When the embryo has died but is retained in the uterus without miscarriage symptoms. Presents with small uterine size with little to no bleeding.
USG dinding of a Missed miscarriage? (2)
Either….
- Empty gestational sac with absent embryonic pole (blighted ovum) or…
- Gestational sac with embryonic pole without cardiac activity
A patient presents with Missed miscarriage, what do we do? (3)
- USG and order B-hCG to confirm (decreasing lvls should be seen)
- Coagulation test (these patients are at risk of DIC)
- Give prostaglandins to dilate the cervix then do courettage
What’s a Septic miscarriage and how is it managed?
- A miscarriage with an infection of uterus and sorrounding area. The infection is either the cause of the miscarriage or occur as a result of a spontanous miscarriage.
- Management: Metronidazole of Levofloxacin (remember this is miscarriage not pregnancy), then prostaglandins, then curettage.
When do we consider a patient to have recurrent miscarriages, and what has to be done right after?
- Patient has recurrent miscarriages when they have 3 or more consecutive miscarriages
- Do a chromosomal testing of both parents!