Published: 2016-12-15

Obstetrical anal sphincter injuries and outcome of primary repair

Gauri J. Desai, Ketaki K. Junnare


Background: OASIs (obstetrical anal sphincter injuries) involve third and fourth degree perineal tears during the process of vaginal birth. It is a grave complication as it can affect quality of life. Incidence of OASIs is on rise in developed countries. We have analyzed OASIs data from a teaching institute in India.

Methods: It was a retrospective study. Data was collected from delivery register, postnatal care OPD register and case sheets of patients with OASIs. Data was analyzed to determine incidence and risk factors. The outcome of primary suturing was assessed as per records in postnatal OPD.

Results: OASIs was detected in 35 patients (incidence 0.42%), third degree perineal tear was seen in 31 patients, while four patients had forth degree tear. Out of these 35 patients 21 were nullipara. Sixteen patients were instrumental deliveries, 13 and 3 delivered by outlet forceps and ventouse respectively. Primary suturing of the tear was done in 34 patients under anaesthesia. Out of 24 patients who followed up in postnatal clinic at six weeks, 14 patients were asymptomatic. Two had faecal incontinence, while eight had perineal pain.

Conclusions: Nulliparity, instrumental delivery, increasing birth weight were high risk factors for obstetrical anal sphincter injuries. Obstetrician needs to be more careful while delivering a patient with multiple risk factors for OASIs. Primary suturing of anal sphincter injury with good post-operative care has a favorable outcome.


OASIs, Parity, Instrumental deliveries, Primary suturing, Faecal incontinence

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Mohamed R, Dixit S, Ashfaq S, Ijeneme U, Nattey J, Das M. Review of management of third and fourth degree perineal tears. Pain. 2014;3:1-6.

Gurol‐Urganci I, Cromwell DA, Edozien LC, Mahmood TA, Adams EJ, Richmond DH, et al. Third‐and fourth‐degree perineal tears among primiparous women in England between 2000 and 2012: time trends and risk factors. BJOG Inter J Obste Gynaecol. 2013;120(2):1516-25.

Poen AC, Felt‐Bersma RJF, Dekker GA, Deville W, Cuesta MA, Meuwissen SGM. Third degree obstetric perineal tears: risk factors and the preventive role of mediolateral episiotomy. BJOG Inter J Obste Gynaecol. 1997;104(5):563-6.

Sultan, Abdul H, Kamm MA, Hudson CN, Bartram CI. Third degree obstetric anal sphincter tears: risk factors and outcome of primary repair. BMJ. 1994;308(6933):887-91.

Hirayama F, Koyanagi A, Mori R, Zhang J, Souza JP, Gülmezoglu AM. Prevalence and risk factors for third‐and fourth‐degree perineal lacerations during vaginal delivery: a multi‐country study. BJOG Inter J Obste Gynaecol. 2012;119(3):340-7.

Gupta N, Rajaram S, Mehta S. Obstetric anal sphincter injury: a clinical audit. BJOG Inter J Obste Gynaecol. 2012;119(9):1152-2.

Handa, Victoria L, Danielsen BH, William W, Gilbert M. Obstetric anal sphincter lacerations. Inter J Obste Gynaecol. 2001;98(2):225-30.