Excessive fear about the childbirth process increases the time spent in labor, a new study says.

Previous research has shown that fear about childbirth may increase the need of an emergency caesarean section during childbirth. Other studies have shown that women who fear about childbirth have complications during delivery and have negative pregnancy outcomes.

The present study looked at 2,206 women who wanted to give birth vaginally. The participants' fear score for childbirth was determined using a test called Wijma Delivery Expectancy Questionnaire.

A score of 85 on this self-reported test meant that the women were afraid of childbirth. Researchers found that 7.5 percent women, 165 participants, had a test score of more than 85.

Women who were afraid of childbirth spent eight hours in the labor room compared to around 6 hours and 28 minutes in labor room spent by women who didn't fear childbirth. Even after adjusting all other factors, researchers found that women afraid of childbirth spent at least 47 minutes more in the labor room.

Another related study also suggested that women with a specific personality type may have more risk of suffering from heightened fear and anxiety about childbirth.

"Fear of childbirth seems to be an increasingly important issue in obstetric care. Our finding of longer duration of labor in women who fear childbirth is a new piece in the puzzle within this intersection between psychology and obstetrics," said Samantha Salvesen Adams, Health Services Research Centre, Akershus University Hospital, University of Oslo, Norway and co-author of the study.

Also, women with fear of childbirth were more likely to deliver by instrumental vaginal delivery (17 percent versus 10.6 percent) and emergency caesarean delivery (10.9% versus 6.8%) as compared to women who weren't afraid of childbirth, the study says.

However, most women who were afraid of natural childbirth eventually delivered vaginally despite longer labor period.

"We found a link between fear of childbirth and longer duration of labor. Generally, longer labor duration increases the risk of instrumental vaginal delivery and emergency caesarean section. However, it is important to note that a large proportion of women with a fear of childbirth successfully had a vaginal delivery and therefore elective caesarean delivery should not be routinely recommended," Adams said

"There are a number of reasons why women may develop a fear of childbirth and this needs to be explored further so that obstetricians and midwives can provide the appropriate support and advice," said John Thorp, BJOG Deputy-Editor-in-Chief.

The study was published in BJOG: An International Journal of Obstetrics & Gynaecology.