London - Women who take ibuprofen in the first six months of pregnancy may harm their daughters’ future fertility, a study suggests.
Scientists found the common painkiller can halve the number of egg cells in girls’ ovaries.
This suggests girls exposed to ibuprofen in the womb may struggle to have a family, as their body makes fewer eggs.
Women are born with all the eggs they will ever have, unlike men who increasingly produce sperm. It means females could go through menopause earlier, running out of time to have a child, or struggle with infertility in later life.
A study led by the French National Institute of Health and Medical Research exposed tissue from human ovaries to ibuprofen. The amount was the same as two to seven days of a woman taking the drug in pregnancy.
They found egg cells either died or failed to grow and multiply at the normal rate. Study co-author Dr Severine Mazaud-Guittot said: "The development of the follicles in the foetus has not been completed by the end of the first trimester, so if the ibuprofen treatment is short then we can expect the ovarian reserve to recover to some extent.
"However, we found that two to seven days of exposure to ibuprofen dramatically reduced the germ cell stockpile in human foetal ovaries during the first trimester of pregnancy and the ovaries did not recover fully from this damage.
"This suggests that prolonged exposure to ibuprofen during foetal life may lead to long-term effects on women’s fertility and raises concern about ibuprofen consumption by women during the first 24 weeks of pregnancy. These findings deserve to be considered in light of the present recommendations about ibuprofen consumption during pregnancy."
The study involved researchers from the universities of Edinburgh and Copenhagen.
Professor Hans Evers, editor of the journal Human Reproduction, said: "These are important findings that require further investigation. However, at this stage it is not possible to say whether the reduced numbers of follicles in tissue samples from baby girls might translate into reduced fertility 30 years later. At present this is speculation and requires long-term follow-up studies of daughters of women who took ibuprofen while in their first three months of pregnancy."