OG13.1-8 | Normal Labour — Glossary

The diagonal line on the partograph positioned 4 hours to the right of the alert line; crossing it requires immediate obstetric assessment and decision to augment or deliver.

The phase of labour defined by cervical dilatation ≥4 cm with regular, painful contractions producing cervical change; the modern WHO threshold (revised from the older 3 cm Friedman criterion).

A communication skill involving full attentive engagement with the speaker — acknowledging pain, reflecting the woman's expressed concerns, and avoiding dismissal — demonstrated to reduce cortisol-mediated labour inhibition when practised during obstetric care.

The protocol to prevent postpartum haemorrhage comprising oxytocin 10 IU IM with delivery of the anterior shoulder, controlled cord traction, and uterine massage; reduces PPH risk by 60–70%.

The diagonal reference line on the WHO partograph starting at 4 cm and proceeding at 1 cm/h; represents the minimum acceptable rate of cervical progress in active labour.

Ultrasound measurement of amniotic fluid in four quadrants; AFI <5 cm = oligohydramnios; a warning sign in post-dated pregnancy indicating reduced fetal-placental circulation.

A pelvic type (~23% of women) with a heart-shaped inlet, convergent sidewalls, prominent ischial spines, and narrow sub-pubic angle; predisposes to deep transverse arrest and operative delivery.

Betamethasone 12 mg IM × 2 doses 24 h apart (or dexamethasone 6 mg IM × 4 doses 12 h apart) given at 24–34 weeks to accelerate fetal lung maturation, reducing RDS, IVH, and neonatal mortality.

A pelvic type (~24% of women) with a long AP oval inlet, straight sidewalls, and wide sacrosciatic notch; favours direct OP or OA engagement; persistent OP delivery more common.

Deliberate puncture of the chorioamniotic membranes using an amnihook or Kocher clamp; also called amniotomy. Performed to assess liquor, accelerate labour, or initiate induction.

An oxytocin receptor antagonist used as second-line tocolysis; IV bolus + infusion; minimal cardiovascular side effects compared to beta-2 agonists; expensive.

A fetal surveillance tool scoring five parameters (amniotic fluid, fetal breathing, fetal movements, fetal tone, CTG) out of 10; scores 8–10 = normal, <6 = concerning; used in post-dated pregnancy monitoring.

A person (partner, family member, or doula) chosen by the labouring woman to provide continuous support during labour; the obstetric team's role is to facilitate, not restrict, companionship unless there is a specific clinical contraindication.

A scoring system for cervical favourability assessing five parameters: dilatation, effacement, station, consistency, and position (total 0–13); ≥8 indicates a ripe cervix favourable for induction.

A qualitative systematic review (Bohren MA et al., PLoS Med 2015) identifying seven overlapping categories of mistreatment of women during facility-based childbirth: physical abuse, sexual abuse, verbal abuse, stigma/discrimination, failure to meet professional standards, poor rapport, and health-system constraints.

A 1933 morphological classification of female pelvic types into four forms — gynecoid, android, anthropoid, and platypelloid — based on the shape of the posterior segment of the pelvic inlet.

The seven sequential positional changes (engagement, descent, flexion, internal rotation, extension, external rotation, expulsion) that the fetal head undergoes to navigate the maternal pelvis in vertex presentation.

A mismatch between the size of the fetal head and the capacity of the maternal pelvis, preventing vaginal delivery; a leading indication for caesarean section.

Transvaginal measurement of cervical length; <25 mm at 16–34 weeks is associated with preterm birth risk; the most reliable predictor of preterm birth by imaging.

The process of cervical softening, effacement, and early dilatation mediated by prostaglandin E2 (PGE2) activating collagenases and metalloproteinases in the cervical stroma; precedes active labour.

The central graphical component of the partograph plotting cervical dilatation (cm) against time (hours); the primary tool for detecting slow progress or arrest of labour.

Infection and inflammation of the chorioamniotic membranes, characterised by maternal fever >38°C, uterine tenderness, foul-smelling discharge, and maternal/fetal tachycardia; a contraindication to expectant management in PPROM.

Assessment of pelvic capacity on vaginal examination, including measurement of the diagonal conjugate, assessment of ischial spines, sacrosciatic notch, sacral curvature, and sub-pubic angle.

The presence of a person of the woman's choice providing continuous emotional, physical, and informational support during labour and delivery; a WHO strong recommendation (2018) associated with improved maternal and neonatal outcomes.

A pelvis in which one or more key diameters fall below the threshold for safe vaginal delivery: OC <10 cm at inlet, interspinous <9 cm at mid-pelvis, intertuberous <8 cm at outlet.

A component of AMTSL in which gentle traction is applied to the umbilical cord while counter-pressure is applied suprapubically (Brandt-Andrews manoeuvre) after signs of placental separation to deliver the placenta.

Descent of a loop of umbilical cord through the cervix alongside or ahead of the presenting part after membrane rupture; a life-threatening emergency causing cord compression and fetal hypoxia.

A placental hormone that rises exponentially in late pregnancy, amplifying the fetal HPA cascade that drives prostaglandin synthesis and cervical ripening at term; acts as a 'placental clock.'

The moment when the largest diameter of the fetal head is encircled by the vaginal introitus and no longer recedes between contractions; the immediate precursor to delivery of the head.

Arrest of fetal head descent at the level of the ischial spines (mid-pelvis) in the transverse position, unable to rotate to occiput-anterior; most common in android-type pelves.

WHO recommendation to clamp the umbilical cord 1–3 minutes after delivery in term, non-compromised neonates to allow placento-fetal blood transfusion, reducing iron deficiency at 6 months.

The AP diameter of the inlet from the lower border of the pubic symphysis to the sacral promontory; approximately 12.5 cm; the only inlet AP diameter measurable on vaginal examination.

The clinical behaviour of treating a labouring woman as an autonomous individual deserving courtesy, explanation, and physical respect — operationalised through introduction, use of the woman's name, explanation before procedures, and avoidance of demeaning language.

FHR decelerations that mirror the contraction (onset and nadir at contraction peak, return before the contraction ends); caused by head compression; a benign CTG pattern.

Passage of the largest transverse diameter of the fetal presenting part (biparietal diameter ~9.5 cm) through the pelvic inlet; clinically, the presenting part is at or below the level of the ischial spines (0 station).

A surgical incision of the perineum to enlarge the vaginal outlet; performed for specific indications (imminent severe tear, instrumental delivery, fetal compromise) and not routinely for all deliveries.

Cardinal movement in which the fetal head extends around the sub-pubic arch as a fulcrum, delivering the occiput first, then the face and chin over the perineum.

Rotation of the delivered fetal head back into alignment with the fetal shoulders after extension, as the shoulders complete their internal rotation in the pelvis.

The positive feedback loop in which stretching of the cervix and vaginal walls during fetal descent stimulates further oxytocin release from the maternal posterior pituitary, accelerating second-stage contractions.

A glycoprotein found at the chorioamniotic-decidual interface; cervicovaginal fFN ≥50 ng/mL at 22–34 weeks predicts preterm birth; negative result (NPV >95%) is most clinically useful to rule out imminent preterm birth.

Magnesium sulphate given at <32 weeks (Zuspan: 4 g IV + 1 g/h) to reduce cerebral palsy and intraventricular haemorrhage in preterm neonates; this is NOT a tocolytic.

The physiological property of uterine contractions where they are strongest at the fundus and diminish toward the cervix, producing an expulsive force that pushes the fetus downward.

Penicillin G 5 MU IV loading then 2.5 MU IV every 4 hours given intrapartum to prevent neonatal Group B Streptococcus sepsis; indicated in all preterm labour and PPROM.

The most common female pelvic type (~50%), characterised by a round inlet, straight sidewalls, non-prominent ischial spines, and wide sub-pubic arch; the best type for vaginal delivery.

Valid consent for a medical procedure requiring four elements: patient capacity (ability to understand), adequate information (nature, purpose, risks, alternatives), voluntariness (freedom from coercion), and documentation — required before each procedure, not once at admission.

Passive rotation of the fetal occiput from the transverse position at the mid-pelvis to the anterior position at the outlet, guided by the inclined plane of the levator ani pelvic floor muscles.

The distance between the ischial spines; approximately 10–10.5 cm; the smallest diameter of the entire pelvis and the critical measurement at the mid-pelvic plane.

The distance between the inner surfaces of the ischial tuberosities; approximately 11 cm; the critical transverse diameter of the pelvic outlet.

Knows How — the NMC CBUC 2024 taxonomy level requiring demonstrated skill in clinical or OSCE context, not merely factual recall; OG13.8 is at KH level, meaning RMC behaviours are directly observable and assessable.

Labour Room Quality Improvement Initiative — a Government of India (MoHFW, 2017) programme to improve quality of care in labour rooms and maternity operation theatres of public-sector facilities, including a discrete domain for respectful maternity care and provider behaviour.

FHR decelerations that begin after the peak of a contraction and return to baseline after the contraction ends; indicate uteroplacental insufficiency; a non-reassuring CTG pattern requiring urgent action.

Antibiotics given in PPROM to prolong the period between membrane rupture and delivery, reducing maternal and neonatal infection; erythromycin is the agent of choice (NOT co-amoxiclav due to NEC risk).

The pelvic brim that separates the false (greater) pelvis above from the true (lesser) pelvis below; composed of the sacral promontory, arcuate line of ilium, pectineal line, and upper border of pubic symphysis.

Classification of meconium-stained amniotic fluid: Grade I (light/thin), Grade II (moderate), Grade III (thick/pea-soup). Grade II-III with fetal heart rate abnormalities indicates significant fetal distress.

Any act or omission by a health facility or provider during facility-based childbirth that fails to uphold the basic rights of women — encompassing physical, verbal, and structural dimensions as classified in the Bohren typology.

A technique for controlled delivery of the fetal head: upward pressure applied to the fetal chin through the perineum while the other hand maintains flexion on the occiput, preventing rapid extension and perineal tearing.

Manyata Surakshit Saatvan — the private-sector complement to LaQshya, a voluntary quality-certification programme for private maternity facilities assessing standardised clinical protocols and patient-centred care including RMC.

A dihydropyridine calcium channel blocker used as first-line tocolysis in preterm labour; 20 mg oral loading then 10–20 mg TDS; blocks calcium-mediated myometrial contraction.

Spontaneous onset of regular uterine contractions producing progressive cervical change at term (37–42 weeks), with vertex presentation, completing without operative intervention.

A loop of umbilical cord around the fetal neck; if loose, slipped over the head after delivery; if tight, double-clamped and cut before shoulder delivery.

The shortest AP diameter of the pelvic inlet, measured from the posterior surface of the pubic symphysis (1 cm below the upper border) to the sacral promontory; normally ~11 cm; the critical determinant of engagement.

Landmark RCT (Kenyon et al., Lancet 2001) demonstrating that erythromycin prolonged latency and reduced neonatal morbidity in PPROM, while co-amoxiclav increased neonatal necrotising enterocolitis.

A WHO-standardised graphical tool for monitoring labour progress, including the cervicograph (dilatation vs time), fetal heart rate, contractions, and maternal vitals; contains alert and action lines.

The imaginary curved line passing through the centres of all pelvic planes, curving downward and backward at the inlet, becoming more direct at the mid-pelvis, then turning forward and downward at the outlet.

The angle between the plane of the pelvic inlet and the horizontal in the erect position; approximately 55 degrees; determines the direction of engagement.

The superior opening of the true pelvis, bounded by the sacral promontory, linea terminalis, and upper border of the pubic symphysis; also called the superior strait or first pelvic plane.

Ensuring the woman's body is covered to the extent possible during examination, curtains or screens are drawn before intimate procedures, and examinations are not conducted as demonstrations without the woman's explicit knowledge and consent.

The rarest pelvic type (~3% of women), characterised by a flat transversely oval inlet with very short AP diameter; carries the highest risk of inlet CPD.

The WHO 2018 framework defining an ideal birth as one that fulfils the woman's personal and sociocultural needs and expectations — effective clinical care in a supportive environment with a companion of choice — the conceptual root of international RMC policy.

A pregnancy extending to or beyond 42 completed weeks of gestation; associated with uteroplacental insufficiency, stillbirth, and meconium aspiration.

Spontaneous rupture of the chorioamniotic membranes before the onset of labour, at any gestational age.

Regular uterine contractions (≥4 per 20 minutes) with documented cervical change before 37 completed weeks of gestation.

PROM occurring before 37 completed weeks of gestation; creates simultaneous risks of ascending infection and preterm birth.

Care provided to all women during childbirth in a manner that maintains their dignity, privacy, and confidentiality; ensures freedom from harm and mistreatment; and enables informed choice and continuous support during labour.

Failure of placental delivery within 30 minutes of active management of the third stage; requires manual removal under anaesthesia to prevent postpartum haemorrhage.

The practice of performing perineal incision prophylactically in all vaginal deliveries — not recommended by the WHO (2018); episiotomy should be selective, performed for specific clinical indications, and only with the woman's informed consent.

The space between the ischial spine and the sacrum, bounded by the sacrospinous ligament; adequate width (2–3 finger breadths) indicates good posterior pelvic capacity.

Impaction of the anterior fetal shoulder against the maternal pubic symphysis after delivery of the head; a life-threatening obstetric emergency requiring specific manoeuvres (McRobert's, suprapubic pressure, internal rotation).

A Bohren mistreatment category encompassing differential treatment based on identity characteristics including caste, religion, HIV status, age, marital status, or socioeconomic background — violates the WRA right to equality and freedom from discrimination.

The angle formed by the two ischiopubic rami at the pubic arch; normally ≥85 degrees in women; narrow (<70 degrees) in android-type pelves, reducing anterior space at the outlet.

The presenting diameter of the well-flexed vertex (~9.5 cm), from the nape of the neck to the anterior fontanelle; the smallest presenting diameter in vertex presentation.

Pharmacological suppression of uterine contractions using agents such as nifedipine, atosiban, or beta-2 agonists; used primarily to buy 48 hours for antenatal corticosteroids.

The AP diameter of the inlet from the upper border of the pubic symphysis to the sacral promontory; approximately 11.5 cm; not clinically measurable.

The part of the pelvis below the pelvic brim (linea terminalis) that forms the birth canal; bounded by the sacrum, hip bones, and pubic symphysis.

FHR decelerations with variable onset, depth, and duration, not consistently related to contractions; caused by cord compression; may be benign or concerning depending on duration and depth.

A Bohren mistreatment category encompassing threatening, blaming, scolding, using derogatory or demeaning language, dismissing pain, and humiliating women — including subtle forms such as ignoring questions or moralising about the woman's circumstances.

A 2011 international normative document articulating seven universal rights of childbearing women, including freedom from harm, informed consent, privacy, dignity, non-discrimination, timely high-quality care, and companionship.

A standardised single-page graphical tool for monitoring labour progress, integrating fetal heart rate, cervical dilatation (cervicograph), contractions, and maternal vital signs; contains alert and action lines.