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Embroyonic and fetal development begins with

fertilizatoin and takes 38 weeks until maturity occurs

Gestational age vs embryonic age

Naegele’s rule

Teratogens will either

• Gestational age is calculated from mothers LMP (usually 2 weeks prior to fertilization) 

• Gestational age is usually 2 weeks older than the embryonic age 

Naegele’s rule can estimate delivery date

• (LMP+7 days- 3months + 1 year)

Teratogens will either kill the fetus or have no effect within the initial 2 weeks of gestation. 

• They cause abnormal organ formation between 2-12 weeks

Timeline of fetal development during gestation

3 days after fertilization: blastocysts enters uterine cavity 

6 days: implantation and form trophoblastic cells and produce beta HCG 

3 weeks: heart begins to form 

5 weeks: early lungs form 

9 weeks: kidneys begin to function 

12 weeks: can tell sex; biliary system begins to form 

17 weeks: fetal movement can be detected

20 weeks: pancreas begins to function 

24 weeks: surfactant production, fingernails present, earliest chance of survival for premature birth 

38 weeks: full term 

low risk activity during pregnancy

Moderate intensity exercise is encouraged 

Sexual intercourse can be continued unless mother is high risk for

• spontaneous abortion,

• premature labor or

• placenta previa 

Changes in pregnancy

CV

Respiratory

CV: 

-CO increased 

-SV increases 

-Systolic murmur increases if present 

-O2 demand on heart increases

-BP increases

-Uterus can displace heart slightly superiorly 

Respiratory: 

-Diaphragm displaces superiorly 

-RV decreased

-FRC decreased 

-Expiratory residual volume decreased 

-Total body O2 consumption increases 

-Tidal volume increases 

-minute ventilation increases 

-PCO2 decreases (chronic respiratory alkalosis with metabolic compensation) 

-progesterone stimulates respiratory drive 

Changes in pregnancy

Renal

endocrine

Renal 

-plasma flow and GFR increase

-decrease in BUN, cr 

-increased renal protein excretion 

-increase renal loss of bicarbonate (compensation for respiratory alkalosis) 

-blood and interstitial fluid volume increases 

Endocrine: 

-nonDM hyperinsulinemia 

-mild glucose intolerance 

-human placental lactogen contributes to glucose intolerance 

-fasting TG increases

-cortisol increases 

-TBG and total T4 increases

-Free T4 unchanged 

-TSH decreases slightly during early pregnancy but wnl still 

Changes in pregnancy

heme

GI

Heme: 

-hypercoaguable 

-increased RBC production 

-decreased Hct 

-increased blood volume 

GI: 

-increased salivation 

-decreased gastric motility 

Assessment of Gestational age

-first trimester

-second trimerster

-after 20 weeks

First trimester

-US with crown-rump length is most accurate

Second trimester: 

-fetal abdominal circumference 

-biparietal diameter

-femur length 

-head circumference  

Afer 20 weeks: 

-fundus height

-note: uterine fibroids and obesity can affect the accuracy of using fundal height measurements 

Prenatal care

-nutrition

-weight gain

Nutrition

-folate and iron 

-avoid fish and caffeine 

Weight gain 

-Ideal weight gain based on BMI 

• <19.8 BMI: 28-40 lbs weight gain 

• 19.8-26 BMI: 25-35 lbs 

• >26 BMI: 15-25 lbs 

-inadequate weight gain can result in fetal growth restriction and preterm delivery 

-too much weight gain can result in GDM, fetal macrosomia and C-section 

Daily caloric intake pregnancy

2500 kcal

Prenatal visits

-Leopold maneuvers

Leopold maneuvers performed in third trimester to determine fetal presentation

Maternal serium alpha protein level test

-Test is only valid if performed during correct gestational window (16-18 weeks gestation) 

-High levels are associated with risk of NTDs, abdominal wall defects, and multiple gestations

-Low levels are associated with inc risk of trisomies 21 and 18 

Screening labs vs length of gestatio n

-initial visit

-16-18 weeks

-18-20 weeks

-24-28 weeks

-32-37 weeks

Initial visit: 

-CBC

-Rh typing

-Pap smear

-STI screening 

-UA

-RPR or VDRL

-Rubella and varicella AB titer 

-HBsAG

-HIV screening (with maternal consent) 

16-18 weeks: 

-Quad screen (maternal AFP, hCG, Estriol, inhibin A) 

18-20 weeks: 

-US dating 

-assessment for gross fetal abnormalities 

24-28 weeks: 

-1-hr glucose challenge for GDM 

32-37 weeks: 

-cervical culture for N. Gonnorhea and chlaymdia

-GBS screen 

High risk pregnancy tests: description and indications

quadruple screen

full integrated test

amniocentesis

chorionic villi sampling

precutaneoous umbilical blood sampling

Full integrated test and quad screen

-trisomy 21

-trisomy 18

-trisomy 13

Gestational DM

-most frequently occurs in the

Most commonly occurs in the 2nd and 3rd trimesters 

(Usually if presentation is earlier then suspect non GDM) 

Continue glucose assessment in patients gestational DM

after birth

Gestational DM pathway

Preeclampsia

-def

-rf

-sxs

-labs

-definitive cure

-tx

-complications

Eclampsia

-def

-sxs

-labs

-tx

-complications

-do not confuse witih

-anticonvulsant use in prgnancy

Maternal asthma (pre-existing)

-def

-sxs

-tx

-complications

Maternal n/v

-timeline

-caused by

-sxs

-tx

-Hyperemesis gravidum

Maternal DVT

-def

-sxs

-dx

-radio

-tx

-complications

Anticoagulation during active labor

stop all anticoagulation during active labor until 6 hours after delivery to prevent severe hemorrhage

Maternal UTIS

-more common because

-sxs

-labs

-tx

-what should you not use for tx

Drug use in mother durign pregnancy

-maternal risks vs fetal risks

• weed

• cocaine

• ETOH

• opiods

• stimulants

• tobacco

• hallucinogens

Teratogens

• ACE-I

• Aminoglycosides

• Carbamazepine

• Chemotherapies

Teratogens

• ACE-I

• Aminoglycosides

• Carbamazepine

• Chemotherapies

Teratogens

-diazepam

-DES
-Fluroquinolones

-Lithium

Teratogens

-phenobarbital

-phenytoin

-retinoids

Teratogens

-sulfonamides

-tetracycline

-thalidomide

-valproic acid

-warfarin

TORCHES

-baby effect

-dx

-tx

• Toxo

• rubella

• rubeola-measles

• syphilis

• cmv

TORCHES

-baby effect

-dx

-tx

• HSV

• HBV

• HIV

• Gonorrhea/chlaymydia

• VZV

• GBS

• Parvovirus B19

Ectopic pregnancy

-rf

-sxs

-labs

-radio

-tx

-complications

Bhcg is produced by

most common cause of vaginal bleeding in early pregnancy

Spontaneous abortion/ Miscarriage

-def

-first tri vs second tri

-rf

-sxs

-labs

-radio

-tx

Sxs/Dx/Tx

threatened abortion

missed abortion

inevitable abortion

incomplete abortion

Intrauterine fetal demise

-def

-caused by

-sxs

-radio

-tx

-complications

-evaluation involves

IUGR

-types symmetric vs asymetric

-sxs

-radio

-tx

-initial us finding

Oligiohydraminos

-def

-associated with

-timing per tri

-sxs

-radio

-tx

-complications

Polyhydraminos

-def

-can result from

-sxs

-radio

-tx

-complications

-can reaccumulate following

PROM

-def

-rf

-what do you not perform

-sxs

-labs

-radio

-tx based on timing

Fetal lung maturity quantified by

Preterm labor

-def

-rf

-sxs

-labs

-radoi

-tx based on timing

-complications

-cervical length

Placenta previa

-def

-types

• low

• partial

• complete

Placenta previa

-rf

-sxs

-radio

-tx

-complications

-after 20 weeks gestation

-do not perform

Abruptio placentae

-def

-rf

-sxs

-radio

-tx

-complications

Benign low back pain in pregnancy

radiates to thighs

worsens with activity

improves with rest

Multi gestaton

-more likely with

-types

-increased incidence of complications mom vs baby

-sxs

-radio

-tx

-conjoined twins only occur in

-twin-twin transfusion syndrome if

Asessment of fetal well being

-nonstress test

Normal fetal HR

120-160

Biophysical profile

Fetal heart rate tracings

-cause and treatment

• early

• late

• variable

Contraction stress test

Fetal scalp blood sampling

Fetal scalp monitoring

During last few weeks of gestation

Stages of labor

Induction of labor

Malpresenttaion

-normal

-face

-brow

-breech: frank, complete, footling/incomplete

• RF

• sxs

• radio

• tx

• complications

Bishop scoring system

Dilation, effacement percent, station, cervical consistency, cervical position

0-3

Vertical vs low transverse C-section

csection indications mom vs baby

subsequent pregnancies

-if vertial incision used previously

-complications

breast milk ideal infant nutrient because

contains IgA Abs for newborn

sufficient supply

cost free

mother-infant bonding

colostrum

Postpartum hemorrhage

-def

-because of

-can also result from

-sxs

-radio

-tx

-retained placental tissue causes

Hydatidiform mole

-def

-types complete vs incomplete

-highly suspect molar prengancy if

-rf

-sxs

-labs

-radio

-tx

-complications

-what is seen in both mole and multigestational pregnancies, differentiate how?

Choriocarcinoma

-def

-sxs

-labs

-radio

-tx

-complications