Table 2.
Main characteristics of included studies
| Study | Country (study period) | Study design | Place of birth | Case identification | Parity | Type of delivery | N (Sample size) | Episiotomy (%) | 2nd degree tear (%) | OASI (%) | NS (%) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Singh and Rathore (2011) | India (August 2007 to February 2009) | Cross-sectional | Medical facility (hospital) | Consecutive sample of operative delivery from medical records (vacuum and forceps) | NS | Operative | 120 | 86.7 | |||
| Calvo et al. (2013) | Mexico (March 2011 to April 2012) | RCT (Cross-sectional data) | Medical facility (hospital) | Low risk pregnancies with singleton pregnancy on cephalic presentation | Mixed | Normal | 78 | 12.8 | 2.6 | ||
| Alayande et al. (2012) | Nigeria (September 2008 to February 2005) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period, based on medical records | Primiparas | Normal | 280 | 34.3 | |||
| Francisco et al. (2011) | Brazil (2007) | Cross-sectional | Medical facility (hospital) | Convenience sample of singleton pregnancies. Women > 15 years | Mixed | Mixed | 303 | 60.7 | 6.6 | 80.5 | |
| Assarag et al. (2013) | Morocco (December 2010 to March 2012) | Cross-sectional | Mixed | Whole population (all women giving birth during study period). Limited to women aged between 18 and 49 years old | Mixed | NS | 1530 | 34.5 | |||
| Baloch et al. (2008) | Pakistan (2005–2006) | Cross-sectional | Medical facility (hospital) | Consecutive sample of vacuum delivery | Mixed | Operative | 160 | 2.5 | 17.5 | ||
| Bello et al. (2010) | Nigeria (August 2008) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period | Multiparas | NS | 375 | 25.1 | |||
| Braga et al. (2014) | Brazil (March 2009 - July 2010) | Case-control (cross sectional data) | Medical facility (hospital) | Convenience sample of assisted vaginal deliveries | Mixed | Mixed | 522 | 33.1 | |||
| Brohi et al. (2012) | Pakistan (December 2009–May 2010) | Case series (Cross-sectional data) | Medical facility (hospital) | Deliveries of singletons in cephalic presentation | Primiparas | NS | 1488 | 3.2 | 3.8 | ||
| Cawich et al. (2008) | Jamaica (2004–2006) | Retrospective case series (Cross sectional data) | Medical facility (hospital) | All vaginal deliveries during study period | Mixed | NS | 3957 | 0.2 | |||
| Chang et al. (2007) | Ecuador (August 2004–January 2005) | Case series (Cross sectional data) | Medical facility (hospital) | Singleton pregnancy with cephalic presentation subjected to vacuum delivery | NS | Operative | 97 | 74.2 | 5.2 | 11.3 | |
| Wai et al. (2015) | China (January 2011–June 2014) | Cohort | Medical facility (Obstetrics and Gynaecology Centre) | All vaginal deliveries of a singleton baby during study period | Mixed | Mixed | 15,526 | 3.2 | |||
| Colacioppo and Riesco (2009) | Brazil (June 2004–December 2004) | RCT (Cross-sectional data) | Medical facility (Birth centre) | Healthy women with singleton pregnancy on cephalic presentation. Age > 15 years old | Primiparas | NS | 105 | 30.5 | 31.4 | ||
| Colacioppo et al. (2011) | Brazil (January 2009–June 2009) | RCT (Cross-sectional data) | Medical facility | Healthy women with singleton pregnancy on cephalic presentation | Primiparas | NS | 77 | 10.4 | 24.7 | 5.2 | |
| Conde-Agudelo et al. (2008) | Colombia (April–December 2006) | Mixed methods | Medical facility (hospital) | All low-risk pregnancies during study period | Primiparas | NS | 1410 | 79.8 | |||
| da Silva et al. (2012) | Brazil (January 2006–December 2009) | Cross-sectional | Medical facility (Birth centre) | All vaginal deliveries during study period | Primiparas | NS | 1079 | 32.2 | 23.6 | ||
| Gómez Dávila et al. (2006) | Colombia (July 2004–April 2006) | Cohort | Medical facilities (1 public hospital and 2 private) | All vaginal deliveries with 24 weeks gestational age, during study period | Primiparas | NS | 669 | 71.4 | |||
| Carvalho et al. (2010) | Brazil (January–December 2006) | Retrospective study (Cross-sectional data) | Medical facility (hospital) | Random sample of whole population | Primiparas | NS | 495 | 29.1 | |||
| Demirel and Golbasi (2015) | Turkey (January 2010 and May 2011) | RCT (Cross-sectional data) | Medical facility (hospital) | Healthy women or second birth, cephalic presentation, gestational age of 37–42 weeks of pregnancy, and in the latent phase of the first stage of labour with dilatation of less than 4 cm and effacement of less than 50% | Mixed | Normal | 142 | 42.2 | 8.4 | ||
| Egbe et al. (2015) | Cameroon (2009–2012) | Cross-sectional | Medical facility (1 hospital and 2 health centres) | Healthy women with singleton pregnancy and gestational age > 28 weeks. Uncomplicated births. Age 14–29 years old | Primiparas | NS | 148 | 3.3 | 18.9 | ||
| Farooq et al. (2010) | Pakistan (2004) | Cohort | Medical facility (hospital) | All deliveries | Mixed | 2563 | 10 | ||||
| Ferdous et al. (2012) | Bangladesh (2007–2008) | Cohort | Mixed (medical facility and community) | Random sample of the whole population | Mixed | NS | 482 | 1.1 | 0.04 | 10.1 | |
| Figueiredo et al. (2011) | Brazil (2008) | Cross-sectional | Medical facility (hospital) | All dystocia-free vaginal deliveries assisted by nurses | Mixed | NS | 447 | 11.2 | |||
| Azam Foroughipour et al. (2011) | Iran (2007–2008) | RCT (Cross-sectional data) | Medical facility (hospital) | For this review only the arm that represented the common practice, the hand group, was considered. Age 15–35 years old | Primiparas | Normal | 50 | 80 | 26 | ||
| Fouelifack et al. (2014) | Cameroon (2008 and 2010) | Intervention study (Cross-sectional data) | Medical facility (hospital) | All vaginal deliveries | Mixed | Mixed | 5045 | 6.7 | 0.4 | < 0.1 | |
| Frass and Al-Harazi (2010) | Yemen (2008) | Cohort | Medical facility | Whole population (all women giving birth during study period) | Primiparas | NS | 2588 | 75.1 | 0.27 | ||
| Fyneface-Ogan et al. (2006) | Nigeria (January to December 2008) | RCT (Cross-sectional data) | Medical facility (hospital) | Data for this review was extracted from repost of records of all vaginal births | Mixed | Normal | 1293 | 37.3 | 1.4 | ||
| Garcia-Elorrio et al. (2014) | Nicaragua (August 2011 and April 2012) | Intervention study (Cross-sectional data) | Medical facility (several medical facilities) | All vaginal deliveries | Mixed | Normal | 766 | 31.2 | 2.7 | 0.3 | |
| Geranmayeh et al. (2012) | Iran (2009) | RCT (Cross-sectional data) | Medical facility (hospital) | All vaginal deliveries with baby in cephalic presentation. Limited to women aged between 18 and 30 years old | Mixed | Normal | 45 | 84.4 | 2.2 | ||
| Gözükara et al. (2015) | Turkey (March–April 2013) | Cross-sectional | Mixed (home and medical facilities at regional level) | All vaginal deliveries | NS | NS | 279 | 99.2 | |||
| Hafeez et al. (2013) | Pakistan (2010–2011) | Case series | Medical facility | Women undergoing vacuum assisted delivery | Mixed | Operative | 67 | 1.49 | |||
| Hasegawa and Leventhal (2009) | Brazil (2008) | Cohort | Medical facility (hospital) | All deliveries | Mixed | Mixed | 130 | 97.8 | |||
| Hassan et al. (2013) | Occupied Palestinian Territory (2005–2006) | Mixed methods (Cross-sectional data) | Medical facility | Interviews with midwives and physicians regarding their practice | Primiparas | Mixed | 134 | 79.9 | |||
| Hirayama et al. (2012) | Algeria (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 13,654 | 7.2 | |||
| Angola (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 6298 | 0.7 | ||||
| DR Congo (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 7894 | 0.9 | ||||
| Kenya (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 17,063 | 1.1 | ||||
| Niger (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 7976 | 2.8 | ||||
| Nigeria (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 7813 | 1.4 | ||||
| Uganda (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 12,135 | 0.6 | ||||
| Cambodia (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 4812 | 0.1 | ||||
| China (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 7867 | 0.1 | ||||
| India (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 20,519 | 0.1 | ||||
| Nepal (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 6817 | 0.5 | ||||
| Philippines (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 10,879 | 15 | ||||
| Sri Lanka 2007–2008 | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 10,494 | 0.4 | ||||
| Thailand (2007–2008) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 6454 | 0.9 | ||||
| Vietnam (2007–2008) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 8607 | 0.3 | ||||
| Argentina (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 6753 | 0.3 | ||||
| Brazil (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 10,720 | 0.7 | ||||
| Cuba (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 8195 | 0.4 | ||||
| Ecuador (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 7437 | 2.2 | ||||
| Mexico (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 13,028 | 0.8 | ||||
| Nicaragua (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 3912 | 0.4 | ||||
| Paraguay (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 2024 | 1.6 | ||||
| Peru (2004–2005) | Cross-sectional | Medical facility | All vaginal deliveries | Mixed | Mixed | 10,655 | 0.3 | ||||
| Ho et al. (2010) | Indonesia (2005) | Before and after study (Cross-sectional data) | Multi country | All vaginal deliveries during study period | NS | NS | 1146 | 53.5 | |||
| Malaysia (2005) | Before and after study (Cross-sectional data) | National (multi country) | All vaginal deliveries during study period | NS | NS | 1700 | 60.6 | ||||
| Philippines (2005) | Before and after study (Cross-sectional data) | National (multi country) | All vaginal deliveries during study period | NS | NS | 1274 | 63.7 | ||||
| Thailand (2005) | Before and after study (Cross-sectional data) | National (multi country) | All vaginal deliveries during study period | NS | NS | 1568 | 91.6 | ||||
| Inyang-Etoh and Umoiyoho (2012) | Nigeria (12months, month and year not reported) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period | NS | NS | 1306 | 21.1 | |||
| Iyengar (2012) | India (January 2007–Dec 2010) | Intervention study (Cross-sectional data) | Mixed (Home and health centres) | All women receiving nurse/midwives home-level postnatal visits | NS | NS | 1156 | 7.1 | 1.2 | ||
| Joshi and Acharya (2009) | Nepal (August 2005–November 2005) | cohort | Medical facility (hospital) | All low risk with singleton pregnancy on cephalic presentation and gestational age between 36 and 42 weeks | Primiparas | NS | 410 | 22.2 | |||
| Kaplan et al. (2013) | Gambia (December 2010–March 2011) | Cohort | Medical facilities | All vaginal deliveries during study period | Mixed | Mixed | 381 | 16 | 27.8 | ||
| Karaçam et al. (2012) | Turkey (2006–2009) | RCT | Medical facility (hospital) | All singleton pregnancies. Limited to women between 18 and 35 years old | Primiparas | Normal | 10,050 | 60.6 | 3.5 | 15.7 | 96.5 |
| Khaskheli et al. (2012) | Pakistan (2006–2010) | Case series (Cross sectional data) | Medical facility (hospital) | All cases admitted in maternity ward. The study included all the women delivering in the hospital and all referred from outside either from local maternity homes, rural health centres and delivery at home within 40 days | Mixed | NS | 9216 | 0.6 | |||
| Khresheh et al. (2009) | Jordan (July–August 2004) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period | Mixed | Mixed | 905 | 54.3 | 0.45 | 15.8 | |
| Koettker et al. (2012) | Brazil 2005–2009 | Cross-sectional | Home | All women with planned home birth (low risk pregnancies) | Mixed | NS | 89 | 1.1 | |||
| Kongnyuy et al. (2008) | Cameroon (2004–2005) | Cross-sectional | Medical facility (hospital) | Singleton pregnancy | Primiparas | Mixed | 1003 | 11.6 | |||
| Saxena et al. (2010) | India (2007) | Cohort | Medical facility (hospital) | All vaginal deliveries during study period | Primiparas | Mixed | 210 | 67.6 | 0.95 | ||
| Moghadam et al. (2015) | Iran | Cross-sectional | Medical facility (multiple health centres) | All vaginal deliveries during study period | NS | Mixed | 400 | 36 | |||
| Moini et al. (2009) | Iran | RCT (Cross-sectional data) | Medical facility (hospital) | Whole population (all women giving birth during study period) | Primiparas | NS | 146 | 51.2 | 7.4 | ||
| Mola and Kuk (2010) | Papua New Guinea (2007) | RCT (Cross-sectional data) | Medical facility (hospital) | Singleton pregnancy with cephalic presentation subjected to vacuum delivery | Mixed | Operative | 100 | 60 | 1 | ||
| Mollamahmutoğlu et al. (2012) | Turkey (June 2007–September 2008) | RCT (Cross-sectional data) | Medical facility (hospital) | Convenience sample of low risk pregnancies | Primiparas | NS | 204 | 89.2 | 1.5 | ||
| Ndiaye et al. (2010) | Burkina Faso (June–August 2007) | Cross-sectional | Medical facility (4 maternity hospitals) | All vaginal deliveries during study period | NS | NS | 330 | 23.6 | 4.5 | ||
| Nguyen et al. (2013) | Vietnam (2011) | Cross-sectional | National | Based on household survey. Cluster sample of pairs of breastfeeding mothers and children under 24 months | NS | NS | 6068 | 41.3 | |||
| Nkwabong et al. (2009) | Cameroon (May to October 2010) | Case series | Medical facility (hospital) | Singleton pregnancy with cephalic presentation | Mixed | NS | 1695 | 9.6 | 0.18 | 86.4 | |
| Njoku et al. (2015) | Nigeria (January 2009–December 2014) | Case series | Medical facility (hospital) | All vaginal deliveries during study period | NS | NS | 15,526 | 9 | |||
| Obioha et al. (2015) | Nigeria (November 2012–June 2013) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period | Mixed | Mixed | 208 | 38 | 6.6 | ||
| Oliveira et al. (2014) | Brazil (2009–2010) | Cross-sectional | Medical facility (hospital) | Vaginal delivery, gestational age > 37 weeks, cephalic presentation | Primiparas | Mixed | 1384 | 25 | 1.1 | ||
| Rathfisch et al. (2010) | Turkey 92,005-2006 | Descriptive prospective (Cross-sectional data) | Medical facility (hospital) | All low-risk pregnant women who expected vaginal delivery at over 38-weeks of gestation with a single foetus in the vertex position | Primiparas | NS | 165 | 67.3 | |||
| Reyes (2011) | Panamá (2007–2009) | Cohort | Medical facility | Whole population (all women giving birth during study period) | Mixed | Mixed | 3573 | 21.6 | |||
| Rojas-Higuera et al. (2006) | Colombia (Aug 2004–March 2005) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries with gestational age > 24 weeks | NS | Mixed | 906 | 56.5 | |||
| Sagili et al. (2012) | India (March 2008–April 2009) | Cross-sectional | Medical facility (hospital) | All vaginal deliveries during study period, based on medical records | Mixed | Mixed | 15,498 | 52.58 | 8.3 | ||
| Saleem et al. (2016) | Pakistan (January–June 2008) | Case series (Cross-sectional data) | Medical facility (hospital) | Consecutive sample of operative delivery (vacuum and forceps) | Primiparas | Operative | 120 | 7.5 | 0.05 | ||
| Salge et al. (2012) | Brazil (2009–2010) | Cross-sectional | Medical facility (maternity hospitals) | All vaginal deliveries during study period, based on medical records | Primiparas | NS | 1129 | 56.3 | |||
| de Oliveira Santos et al. (2012) | Brazil (2009) | RCT (Cross-sectional data) | Medical facility (hospital) | All vaginal deliveries during study period, based on medical records | Mixed | NS | 1872 | 18.8 | 40.9 | ||
| Santos et al. (2008) | Brazil (July to December 2006) | Cross-sectional | Medical facility (hospital) | All women giving birth during study period | NS | NS | 246 | 90.2 | 3.3 | ||
| Shahraki et al. (2011) | Iran (October 2007–September 2008) | Cross-sectional | Medical facility (hospital) | Healthy women | NS | NS | 36 | 17.5 | 2.5 | ||
| Shirvani and Ganji (2014) | Iran (September 2011–March 2012) | RCT (Cross-sectional data) | Medical facility (2 hospitals) | Healthy women, age of 18–35, gestational age of 37–41 weeks, single pregnancy, cephalic presentation and cervix dilatation of 3–4 cm | Primiparas | NS | 32 | 94 | |||
| Sooklim et al. (2007) | Thailand (April 2005–February 2006) | Prospective cohort | Medical facility (hospital) | Deliveries of singletons in cephalic presentation. All received episiotomy | Primiparas | NS | 1302 | 9.5 | |||
| Sorensen et al. (2011) | Tanzania (2008) | Prospective intervention study | Medical facility (hospital) | Not clear | Mixed | NS | 510 | 18.4 | |||
| Spitzer et al. (2014) | Kenya (August–November 2011) | Prospective cohort | Medical facility (hospital) | All vaginal deliveries during study period | Mixed | Mixed | 1451 | 13.2 | 2.5 | 0.6 | |
| Sulaiman et al. (2013) | Malaysia (2009) | RCT (Cross-sectional data) | Medical facility (hospital) | Healthy women with singleton pregnancy on cephalic presentation | Primiparas | NS | 82 | 96.3 | 3.7 | ||
| Vogt et al. (2011) | Brazil (2006) | Cross-sectional | Medical facility (3 hospital) | All low risk pregnancies | Mixed | NS | 277 | 7.2 | |||
| Waheed et al. (2012) | Pakistan (2009–2010) | Quasi experimental | Medical Facility | Singleton pregnancy subjected to operative delivery. Women aged between 20 and 40 years | NS | Operative | 60 | 1.7 | 58.3 | ||
| Wang et al. (2014) | China (December 2010–March 2011) | RCT (Cross-sectional data) | Medical Facility (3 hospitals) | Healthy women, singleton, 16–32 weeks of gestation | Primiparas | Normal | 28 | 47.1 | 7.8 | ||
| Yadav et al. (2008) | Nepal (July 2005–June 2006) | Cohort | Medical facility (hospital) | Whole population (all women giving birth during study period) | Mixed | Normal | 4101 | 12.6 | |||
| Zhu et al. (2012) | China (September 2007–May 2009) | Cross-sectional | National | All women giving birth during study period | Mixed | Mixed | 5013 | 69.7 | 21 |
NS not stated