Prenatal unit

1st trimester time frame

Conception to 13.6 weeks

2nd trimester time frame

14 to 26.6 weeks

3rd trimester time frame

27 weeks to end of pregnancy

Normal amount of amniotic fluid at term

700-800 mL

Chadwick's sign

Congestion of blood in the cervix that causes it to have a purpleish appearence

Goodell's sign

Cervical softening in response to hormones that allow for dilation

Total blood volume increases how much


Morning sickness begins around _____ and usually subsides around

4 weeks and 16 weeks

Causes of heartburn in pregnancy

Diminished gastric motility Displacement of stomachRelaxation of esophageal sphincter Increased of Intra-abdominal pressure

Presumptive changes in pregnancy

AmenorrheaN/VFatigueUrinary frequencyBreast and skin change Quickening

Probable Changes in pregnancy

Changes observed by examiner:Enlargement of abdomenCervical softening (Goodell's sign)Cervix and vagina purplish color (Chadwick's sign)Ballottement- fetus rises when touched at cervixUterine consistency softens (Hegar's sign)Palpation of fetal outlineUterine souffle- a soft blowing sound may be auscultated over the uterus.Positive pregnancy test

Positive changes in pregnancy

Fetal heartbeat- can be heard about8-12 weeksFetal movement palpated by a trained providerVisualization of fetus by ultrasound

Foods to avoid in pregnancy

Unpasteurized cheese/milkRaw cookie dough or cake batterSushiRaw or undercooked seafood/fishUnpasteurized juice/cider, fresh squeezed Deli meats or products made in store(ham, chicken, hot dogs, seafood salads)- can have but must be heated in microwaveRaw or undercooked meat

1st 2 weeks of pregnancy correlate with

Development of the oocyte and endometrial lining

Fetal heart starts beating around

4-8 weeks gestation

3 phases of ovarian cycle

Follicular phaseOvulatory phaseLuteal phase

3 phases of endometrial cycle

Proliferative phaseSecretory phaseMenstrual phase


Spontaneous abortion (miscarriage)

Factors influencing fetal development

Quality of spermGenesAdequacy of uterine environment

Corpus luteum eventually becomes

The placenta

Fertilization occurs in the

Fallopian tubes

Primigravida (primipara)

Pregnant for the first time

Multigravida (multipara)

Pregnant more than one time

Fetal development occurs

Head to toeCentral to peripheralSimple to complexGeneral to specific (limbs before bones and joints)

4 weeks gestation

Neural tube closedFetal heart begins to beat, begins to form 4 chambersBlood circulatesArm and leg buds present

At 4 weeks

Mom usually doesn't even know she's pregnant

8 weeks gestation

All body organs are formed1st indication of MS ossification4 chamber heartHeartbeat detectable with ultra sound

Fetal period

From 9th week until birth

12 weeks gestation

Sex of fetus is differentiated, distinguished by appearanceSucking reflex present Kidneys are able to secrete urineHeartbeat detectable by Doppler Lanugo begins to develop


Fine peach fuzz that develops all over the fetus's bodyHelps vernix to stick to skin

Sex of fetus

Determined at conception Genitalia formed by 12 weeksSex of fetus best visualized on US btwn 16-20 weeks

16 weeks gestation

Face looks humanSwallows amniotic fluid and produces meconium (first stool)Pulmonary vascular system developing rapidlyLower limbs reach final relative length, longer than upper limbsMay feel fetal movement

20 weeks gestation

peristalsis well developed Quickening occursBrain formedVernix present lanugo presentBrown fat production


Fetal movement felt by mom


Cheeses substance developed on fetus's skin helps protect skin while in amniotic fluid

24 weeks gestation

Body lean, well proportioned, wrinkled and redSurfactant productions begins in lungs (protects alveoli) Viable- able to live outside the uterus but will need assistanceEyebrows and eyelashes present Skin is very thin

28 weeks gestation

Subcutaneous fat present, not as wrinkled Eyes begin to closeWeak suck reflexTaste bitter

32 weeks gestation

CNS mature (start to see variability on fetal monitor /not much there prior to 32 weeks/)Skin smooth and pigmented Fingernails reach tip of fingersAware of sounds outside mom's bodyLanugo starts to shed and closer to birth

Delivery term 37-40 weeks gestation

Skin pink, round, and plumpLanugo on upper body onlyVernix scantFingernails extend past fingertipsEar cartilage firmGirls have about 1,000,000 follicles in ovariesReceives passive antibodies from mom (don't last very long once infant is born)

3 auxiliary structures

Placenta, embryonic membranes, amniotic fluid


Development/circulation begins at 3rd weekBlood circulates btwn embryo and chorionic viliFully functioning by 12 weeks40 wks: 6-8in diameter, 1/2 in thick, weigh 14-21 oz (1/6 weight of infant)

Maternal and fetal blood

Do NOT mix

Placenta Duncan

Maternal side of placenta

Placenta Shultz

Fetal side of placenta

Amniotic fluid is made up of

A lot of Fetal urine, also contains epithelial cells and vernix

Once water breaks there

Is no barrier to infection for the infant

Collectively the amnion and the chorion layers form the

Bag of waters

Abnormally small amount of amniotic fluid is considered

Less than 50% of amount expected for gestation or 400 mL at term