How do sustained birth tears after vaginal birth affect birth tear patterns in a subsequent birth?

Abstract

BackgroundTears are common after vaginal birth, and different impact factors are known. However, the impact of tears from a previous birth to the tears of a subsequent birth is unknown. Therefore, we aimed to evaluate the distribution of birth tear patterns according to the sustained tears in a previous birth, in addition to other impact factors.MethodsIn a retrospective cohort study, we evaluated all women up to parity 4 with subsequent vaginal, singleton births of vertex presentation at ≥37 + 0 gestational weeks between 1/2005 and 12/2016. Their tears were grouped into tear patterns and were analyzed by parity. Tear patterns in the subsequent births were analyzed in association to the patterns of the previous births and impact factors were evaluated.ResultsWe counted 4017 births in 1855 women [P1: 1368 (34.1%), P2: 1730 (43.1%), P3: 741 (18.4%), P4: 178 (4.4%)]. The frequency of tears and episiotomies decreased with higher parity, whereas the frequency of intact perineum increased. Twenty-eight different unique tear patterns were found. We could show that birth tear patterns changed with increasing parity and were associated with sustained tears in a previous birth. In addition, some impact factors on tear patterns could be identified.ConclusionThe distribution of the single tear types is in accordance with the current literature. However, it is new that distinct tear patterns are associated to sustained tear patterns of previous births. Furthermore, we demonstrated some weak associations of tear patterns to certain impact factors, such as more episiotomies, low-grade perineal or vaginal tears isolated or in combination with other tears with increasing fetal weight and head circumference in the higher parities, and with a longer duration of the second stage and the pushing phase in lower parities.

Birth tears after spontaneous and vacuum-assisted births with different vacuum cup systems – a retrospective cohort study

“…The here presented distribution of the different tear types in SB and vacuum birth is in accordance with the literature [4,5,8,9,16,17]. We know that tear patterns do differ between births of different parities and that they are associated with sustained tear patterns of previous births [18]. Therefore, some of the differences in tear distribution between spontaneous and vacuum births in our study will be explained just by parity.…”

“…Therefore, some of the differences in tear distribution between spontaneous and vacuum births in our study will be explained just by parity. Additionally, different maternal, fetal and obstetrical parameters are associated with different birth tear patterns in women of differing parity and according to the birth mode and rate of episiotomies [16][17][18][19][20][21]. The more episiotomies were performed, the less perineal, labial and paraurethral tears were found, as could be seen in our data.…”

Influence of previous delivery mode on perineal trauma risk

“…There is a paucity of evidence regarding the impact of the previous mode of delivery on severe perineal trauma (OASIs) in subsequent pregnancy. Recent studies have evaluated the risk of OASIs in women with previous perineal trauma, in particular those delivering by vaginal birth after caesarean (VBAC) [8][9][10][11][12]. However, the risk of OASIs is unclear, as their results are contradictory.…”

“…Recent studies have evaluated the risk of OASIS in women with previous perineal trauma, in particular those delivering by vaginal birth after cesarean (VBAC). 8 , 9 , 10 , 11 , 12 However, the risk of OASIS is unclear, as their results are contradictory. D’Souza et al 9 reported a 1.4‐fold increase of OASIS after VBAC compared with primiparous women, and a protective role of mediolateral episiotomy as well as higher incidence if the previous cesarean section (CS) was urgent.…”