NORMAL LABOR AND NORMAL LABOR AND DELIVERY DELIVERY

Eyal Sheiner M.D.Eyal Sheiner M.D.

Soroka University Medical Soroka University Medical CenterCenter

"Labor": Contractions and cervical "Labor": Contractions and cervical dilatationdilatation

PassengerPassenger PowerPower Passageway (Passageway (Pelvis)Pelvis)

The final The final common common pathway of pathway of this this stimulation is stimulation is the creation the creation of of rhythmic rhythmic membrane membrane depolarizationdepolarization in the in the myometrial myometrial cells resulting cells resulting in an increase in an increase in intrauterine in intrauterine pressure.pressure.

PowerPower

Uterine contractionsUterine contractions

Smooth muscle, but painfulSmooth muscle, but painful

PassengerPassenger

PresentationPresentation

LieLie

Position, Position, StationStation

Diameters of the fetal head at Diameters of the fetal head at termterm

Locating the sagittal suture by vaginal Locating the sagittal suture by vaginal examinationexamination

Longitudinal lie. Cephalic presentation.Longitudinal lie. Cephalic presentation. Differences in attitude of fetal body in (A) vertex, (B) Differences in attitude of fetal body in (A) vertex, (B)

sinciput, (C) brow and (D) face presentations.sinciput, (C) brow and (D) face presentations.

Note changes in fetal attitude in relation to fetalNote changes in fetal attitude in relation to fetal vertex as vertex as the fetal head becomes less flexedthe fetal head becomes less flexed

Transverse lie. Right acromiodorsoposterior position Transverse lie. Right acromiodorsoposterior position (RADP)(RADP)

The shoulder of the fetus is to the mother’s right, and The shoulder of the fetus is to the mother’s right, and the back is posteriorthe back is posterior

Longitudinal lie. Vertex presentationLongitudinal lie. Vertex presentationA. Right occiput posterior (ROP) B. Right occiput A. Right occiput posterior (ROP) B. Right occiput

transverse (ROT)transverse (ROT)

When the lowermost portion of the fetal head is above the When the lowermost portion of the fetal head is above the ischial spines, the biparietal diameter of the head is not ischial spines, the biparietal diameter of the head is not likely to have passed through the pelvic inlet and therefore is likely to have passed through the pelvic inlet and therefore is not engaged (P = sacral promontory , Sym = symphysis not engaged (P = sacral promontory , Sym = symphysis pubis).pubis).

Head not engagedHead not engaged

EngagementEngagement

Normal female pelvis with the false and true Normal female pelvis with the false and true pelvis identifiedpelvis identified

The four parent pelvic types of the Caldwell-Moloy The four parent pelvic types of the Caldwell-Moloy classificationclassification

A line passing through the widest transverse A line passing through the widest transverse diameter divides the inlet into posterior (P) and diameter divides the inlet into posterior (P) and anterior (A) segments.anterior (A) segments.

((II ( (Gynaecoid Gynaecoid pelvis (50%(pelvis (50%(

Best suited for child Best suited for child bearing, fortunately bearing, fortunately most commonmost common

Gynecoid pelvis

((IIII ( (Android Android pelvis (20%(pelvis (20%(

It is a male It is a male type, not type, not favorable for favorable for deliverydelivery

Android pelvis

Gynecoid VS Android

Stages of laborStages of labor

The first stage is cervical dilatationThe first stage is cervical dilatation The second stage is labor and delivery The second stage is labor and delivery

of the babyof the baby The third stage is delivery of the The third stage is delivery of the

placenta or afterbirthplacenta or afterbirth On average it takes about 12 to 14 On average it takes about 12 to 14

hours for nulliparous patients and about hours for nulliparous patients and about eight hours for multiparas.eight hours for multiparas.

First stageFirst stage The first stage of labor results in The first stage of labor results in

the cervix dilating to a full 10 the cervix dilating to a full 10 centimeters and consists of latent centimeters and consists of latent and active phases. and active phases.

Active Active PhasePhase

The cervix will The cervix will dilate dilate toto 10 10 centimeters centimeters Contractions Contractions become become intenseintense

Second stageSecond stage Once the cervix has dilated to 10 Once the cervix has dilated to 10

centimeters, the work of the centimeters, the work of the second stage begins--delivering second stage begins--delivering the baby.the baby.

Involuntary urge to push.Involuntary urge to push. This stage can last anywhere from This stage can last anywhere from

minutes to three hours minutes to three hours

The third The third stagestage

Placental Placental separationseparation

Latent Latent phasephase

This phase can This phase can be reached over be reached over a period of days a period of days or in as little as or in as little as two to six hourstwo to six hours