Idea Transcript
Nor mal labor and deliver y L. Sekhavat M.D
Ter minology • Gr avida - number of pr egnancies • Par a - number of pr egnancies car r ied to • • • • •
viability and deliver ed Viability - able to sur vive outside the womb (24+ weeks gestation) Pr imigr avida - pr egnant for fir st time Multigr avida - pr egnant mor e than once Nullipar ous - never car r ied a pr egnancy to viability Multipar ous - has had two or mor e deliver ies that wer e car r ied to viability
Dur ation of Pr egnancy • Aver age 280 days or 40 weeks
(9 lunar months) • Estimated Date of Confinement (EDC) Nagele’s r ule : – Date of fir st day of LMP – Subtr act 3 months – Add 7 days • Accur ate to plus or minus 2.5 weeks
Theor ies of par tur ition • Retr eat fr om pr egnancy
maintenance – Repr ession of contr actile inhibitor s
• Uter otonin induction of
contr actions – Synthesis or activation of factor s
that incr ease uter ine contr actility
• Combination of both
Onset of Labor • • • • • • •
Pr ogester one withdr awal theor y Estr ogen Oxytocin Pr ostaglandins Fetal effect Uter ine distention CRF
Endocr inology of par tur ition
E/P r atio changes becomes > 1
Hor mones and par tur ition maternal progesterone
maternal estradiol
fetal cortisol
7
6
5
4
3
2
days before parturition
1
0
Incr eased E/P r atio causes: • Oxytocin r eceptor s r ise in the uter us Inhibition
of uter ine contr actions is now limited Labor begins • Incr eased pr oduction of Oxytocin • Incr eased pr oduction of PGF 2α
Fetal ejection r eflex Stimulation or distention of cer vix, uter us, or vagina r esults in neur al feedback tur ning on the secr etion of Oxytocin
Requir ements for bir th • Uter ine contr actions For ceful Coor dinated
• Cer vical changes Effacement Dilation
Char acter istics of Tr ue and False Labor • Regular Contr actions • Contr actions str onger , longer , • • • •
closer together Bloody show often pr esent Cer vix effaced and dilated Head is fixed between contr actions Sedation does not stop tr ue labor
Histor y • Identifying infor mation- age, gr avida, • • • • •
par a, weeks gestation Labor histor y- uter ine contr actions, status of membr anes, vaginal bleeding Pr esent pr egnancy histor y Past obstetr ic histor y Past medical/sur gical histor y Past family histor y
Pr ematur e Ruptur e of Membr anes • Spontaneous r uptur e of membr anes
pr ior to the onset of labor is known as pr ematur e r uptur e of membr anes (PROM). • Pr eter m PROM (PPROM) is the r uptur e of membr anes befor e 37 weeks gestation. • Pr olonged r uptur e of membr anes is r uptur e mor e than 24 hour s befor e bir th.
PROM • Risk of pr eter m labor and
pr eter m deliver y • Risk of chor ioamnionitis • Risk of cor d compr ession
The Diagnosis of PROM • Dir ect obser vation of amniotic fluid in
the vagina is the single best confir ming test • Diagnosis may be “confir med” by: Alkaline
pH (nitr azine paper )
Fer ning Demonstr ation
of fetal fibr onectin Indigo car mine dye
Physical Examination • Basic physical exam • Uter ine contr actions:
Fr equency Intensity Dur ation
• Uter ine fundus: Fundal height Fetal lie Estimated fetal weight
Fetal Lie
Leopold maneuver
Fir st Stage of Labor • Begins with onset of coor dinated
contr actions leading to dilation of cer vical os and ends with complete dilation (10 cm) of the cer vical os. • False Labor (Br axton Hicks contr actions) Cer vix
fails to dilate gr eater than 2 cm
• Dur ation of fir st stage Pr imigr avida:
12 hour s Multipar ous: 7 hour s or less
Fr iedman Labor Cur ve- Nullipar ous Patient
Fir st Stage Contr actions • Inter val
10 to 20 minutes between contr actions: ear ly labor 3 to 5 minutes between contr actions: late labor • Dur ation 20 second long contr action: ear ly labor 40 to 80 second long contr action: late labor • Quality Uter us can be dented (poor quality): ear ly labor Uter us is har d (good quality): late labor
Fir st Stage Management • Take VS between contr actions • Fetal Hear t Rate should be between
120 - 160 BPM • Mother should be coached to r elax and conser ve ener gy between contr actions
Assessing Pr ogr ess of Labor Vaginal Exam: • Cer vix Soft
or Har d Effaced or Thick Dilatation
• Pr esentation Par t
(cephalic, br eech, shoulder ) Flexion, Extension Station
Cephalic Pr esentations
Br eech Pr esentations
Lab Tests CBC with platelets Clot tube to hold Ur inalysis- pr otein, glucose, ketones Ur ine dr ug scr een- unr egister ed, disor iented, pr ior dr ug histor y or medical r eason • Pr enatal labs- type, Rh, RPR, HBsAG, Rubella, HIV • • • •
Mechanism of Labor Positional movements the fetus under goes to accommodate itself thr ough the mater nal pelvis • • • • • • •
Engagement Descent Flexion Inter nal r otation Extension Exter nal r otation Bir th of the shoulder s
Fetal Station
Engagement
Flexion
Second Stage of Labor • Begins with complete dilation of the
cer vix and ends with deliver y of fetus • Dur ation
pr imigr avida: 50 minutes
Multiparous:
20 minutes or less
• Contr actions Inter val:
2 to 3 minutes Dur ation: 50 to 100 seconds
Second Stage of Labor • Management Mother
may feel ur ge to push, coach to push only dur ing a contr action once the cer vix has been deter mined to be fully dilated
• Episiotomy Per for m
to avoid unecessar y tear ing when head is cr owning Contr olled deliver y avoids need for episiotomy in most cases
Second Stage of Labor • Deliver y of head
Contr ol head to pr event explosive deliver y and subsequent tear ing
• Check for pr esence of cor d ar ound neck • Aspir ate or al and nasal cavities with bulb
syr inge • Deliver anter ior shoulder with downwar d pr essur e • Complete deliver y
Second Stage of Labor • Clear air way, Assess r espir ations,
Resuscitate if necessar y • Clamp cor d when pulsations cease • Leave 3 - 6 inches of cor d on baby • Obtain blood for fetal labs fr om the placental stub of cor d
Thir d Stage of Labor • Begins after deliver y of baby and ends
with deliver y of the placenta • Aver age dur ation: 8 minutes • Signs of separ ation Uter us
r ises to become globular Incr ease (gush) of blood fr om vagina Lengthening of cor d • Do not PULL cor d. Apply gentle tr action • Check Placenta for completeness
Thir d Stage of Labor • Recover missing pieces of placenta
as necessar y • Massage uter us to aid in hemostasis • IV Oxytocin can be given if available to aid uter ine contr actions and aid in hemostasis
Four th Stages of Labor • Begins with bir th of the placenta and
ends one hour later • Highest r isk to mater nal well-being • Obser vations- examine uter us for fir mness, inspect cer vix, vagina, per ineum for lacer ations and r epair , evaluate mater nal vital signs, examine the baby