Background
Over the last decade the incidence of obstetric anal sphincter injuries (OASIS) has been steadily increasing locally and internationally. Investigations into reducing rates, and the long‐term complications, of OASIS are required.

Aims
To determine if applying a new method of perineal guarding at the time of delivery reduces the incidence of OASIS at an Australian tertiary hospital.

Materials and Methods
A retrospective audit was performed for the three  years prior to and following mandatory introduction of a new method of perineal guarding. The novel ‘Please Squeeze’ technique involved placement of the accoucheur’s thumb and index finger just above the line of the posterior fourchette at crowning and bringing them firmly one centimetre postero‐medially to reduce tension. Demographic data were extracted from the unit’s obstetric database (ObstetriX).

Results
There were 9453 deliveries prior to, and 9805 deliveries following commencement of ‘Please Squeeze’, with no difference in the incidence of caesarean (30.4% vs 30.3% P = 0.87) or forceps (6.3% vs 5.8% P = 0.14) between groups. The incidence of primiparas (P = 0.005), ventouse (P < 0.001) and spontaneous vaginal deliveries (SVD) (P = 0.005) between groups. There was a clinically important 20% reduction in the incidence of OASIS across all vaginal deliveries from 3.5% to 2.8% (P = 0.006). In SVD, there was a 20% decrease in OASIS from 2.4% to 2.2% (P = 0.02), and a 14% decrease in OASIS with assisted vaginal delivery from 8% to 7.3% (P = 0.002). The incidence of episiotomy increased 16% (P < 0.001). Conclusions The novel ‘Please Squeeze’ perineal guarding method contributed to a reduced incidence of OASIS in an Australian tertiary hospital.