What are the recurrent and non-recurrent causes of Lower Segment Cesarean Section (LSCS)?

Recurrent and Non-Recurrent Causes of Lower Segment Cesarean Section (LSCS)

Recurrent Causes (Indications that persist across pregnancies)

Recurrent causes are maternal or fetal conditions that remain present or likely to recur in subsequent pregnancies, making repeat cesarean section necessary or highly probable.

Maternal Anatomical/Structural Factors

• Previous cesarean section itself is the most common recurrent indication, with the overall uterine rupture risk being 22 per 10,000 births (0.22%) in women with prior CS, increasing to 35 per 10,000 (0.35%) when labor occurs 1
• Contracted pelvis or cephalopelvic disproportion (CPD) - anatomical pelvic dimensions do not change between pregnancies, making vaginal delivery persistently difficult or impossible 2
• Uterine structural abnormalities including bicornuate uterus, septate uterus, or other congenital malformations that obstruct the birth canal 2
• Previous classical (vertical) cesarean scar - this is an absolute contraindication to trial of labor due to significantly higher rupture risk compared to lower segment scars 1

Maternal Medical Conditions

• Chronic medical conditions including severe cardiac disease, certain neurological conditions (like previous spinal injury with paraplegia), or conditions where Valsalva maneuver is contraindicated 3
• Placenta accreta spectrum disorder with conservative management - women who had expectant management have a 13.3-28.6% recurrence rate in subsequent pregnancies 3
• Thrombophilia and high-risk conditions requiring anticoagulation that may complicate vaginal delivery 3

Fetal/Obstetric Factors

• Recurrent malpresentation - some women consistently have breech or transverse presentations due to uterine shape, laxity, or fetal factors 2
• Genetic conditions causing macrosomia or other fetal abnormalities incompatible with vaginal delivery 2

Non-Recurrent Causes (Indications specific to current pregnancy)

Non-recurrent causes are acute or pregnancy-specific conditions that may not be present in future pregnancies.

Acute Obstetric Emergencies

• Fetal distress - acute compromise of fetal well-being requiring immediate delivery 4, 2
• Placental abruption - acute separation of the placenta from the uterine wall 3, 1
• Cord prolapse - umbilical cord presenting before the fetus, requiring emergency delivery 2
• Uterine rupture or impending rupture - acute complication during labor 1, 5

Pregnancy-Specific Complications

• Placenta previa - placental implantation over the cervical os, which occurs with equal frequency regardless of number of previous CS 5
• Placenta accreta spectrum at primary diagnosis - risk increases dramatically with each CS (12.9/10,000 after one CS, 41.3/10,000 after two CS, 78.3/10,000 after three CS) 6
• Severe preeclampsia/eclampsia or HELLP syndrome requiring urgent delivery before labor can be safely induced 3
• Failed induction of labor - women with previous CS who undergo induction have higher rates of repeat CS (OR 1.52; 95% CI 1.26-1.83) and lower vaginal delivery rates (OR 0.66; 95% CI 0.55-0.80) 7

Labor-Related Complications

• Failure to progress in labor - slow cervical dilatation (mean ADR 0.42 cm/hour in those requiring repeat CS versus 1.41 cm/hour in successful VBAC) 8
• Obstructed labor due to asynclitism, deflexed head, or other positional abnormalities 2
• Prolonged second stage with maternal exhaustion 8

Malpresentation (Current Pregnancy)

• Breech presentation in current pregnancy (may or may not recur) 2
• Transverse lie at term 2
• Brow or face presentation 2

Technical/Surgical Factors

• Dense intra-abdominal adhesions discovered during current surgery - significantly more common with three or more previous CS (P < 0.05) 5
• Difficult fetal extraction due to deeply engaged head, particularly in emergency CS during advanced labor 2
• Bladder injury risk - higher in women with three or more previous CS compared to one previous CS (P < 0.05) 5

Critical Clinical Distinctions

The key difference is that recurrent causes require counseling about likely repeat CS in future pregnancies, while non-recurrent causes may allow consideration of vaginal birth after cesarean (VBAC) in subsequent pregnancies 9. However, each additional CS increases surgical complications including dense adhesions and bladder injury 5, making the distinction between recurrent and non-recurrent indications crucial for long-term reproductive planning.

Important Caveats

• Inter-pregnancy interval matters - intervals less than 18 months increase uterine rupture risk even with non-recurrent initial indications 6, 1
• Multiple previous cesareans (≥3) create their own recurrent risk due to surgical complications regardless of original indication 5
• Some "non-recurrent" causes may recur - for example, failed induction or failure to progress may indicate underlying CPD that wasn't initially recognized 8, 7