Assumptions women who give birth by Caesarean will not later suffer urinary or faecal incontinence have been challenged by a large long-term study of births in Dunedin, Aberdeen and Birmingham.
A lead researcher in the study, University of Otago Professor of Obstetrics and Gynaecology Don Wilson said he hoped women considering their options for delivering their babies would note the study findings.
It involved surveying 3763 women from maternity units at Dunedin, Aberdeen and Birmingham three months after giving birth, six years and 12 years.
The study found that 40% of those who had their babies delivered exclusively by Caesarean section, still reported urinary incontinence.
The results also showed there was no difference in the occurrence of faecal incontinence between women who had only natural deliveries and those who had only caesareans.
Women who delivered only vaginally had a higher rate of urinary incontinence at 55%, with a slightly higher rate for women who had at least one baby naturally and another through a Caesarean.
Prof Wilson said the study also suggested more women suffered faecal incontinence following forceps-assisted deliveries and that using vacuum-assisted deliveries could be preferable.
The women will be surveyed again in 2014.
The study was begun in 1993, to determine whether pelvic floor exercises to strengthen muscles after birth worked to reduce both types of incontinence.
Prof Wilson said while there was some improvement noted in the first year after delivery, after six and 12 years there was no difference.
It appeared women had mostly stopped doing the exercises.
Further study was being done on about 500 women in the three centres to see if a Pilates programme could prevent prolapse.
In Dunedin, about 80 women were taking part in this at the School of Physiotherapy, but sessions were open to women not in the study.
More and more people were trying to make pelvic floor muscle training part of regular exercise routines, but sometimes it was difficult for women who were not having symptoms to approach it with enthusiasm long-term.
Having a baby by any method increases the likelihood of incontinence but the risk is higher again for women 35 and older when they first give birth, and women who are overweight.
The risk increases with the number of babies delivered.
At the six-year point, the research also showed that there was almost no difference in women's rating of their sexual function between those who had Caesarean births and those who had vaginal births.
Prof Wilson said the women who had Caesarean births rated their vaginal tone as being better than women who had delivered naturally, but the reported interest and ability to reach orgasm was no different from the other groups.
The most recent study results have been published online in international journal of obstetrics and gynaecology BJOG
