Induced labor may be more painful for the woman as one of the side effects of intravenous oxytocin is increased contraction pains, mainly due to the rigid onset. This may lead to the increased use of analgesics and other pain-relieving pharmaceuticals. These interventions may also lead to an increased likelihood of caesarean section delivery for the baby. However, studies into this matter show differing results. One study indicated that while overall caesarean section rates from 1990–1997 remained at or below 20 per cent, elective induction was associated with a doubling of the rate of Caesarean section. Another study showed that elective induction in women who were not post-term increased a woman's chance of a C-section by two to three times. A more recent study indicated that induction may increase the risk of caesarean section if performed before the 40th week of gestation, but it has no effect or actually lowers the risk if performed after the 40th week.