The researchers looked at reproductive age women, between 18 and 53, as menstruation is known to lower iron levels.

BBC: Iron pills may help women beat fatigue

Writing in JAMA, the researchers led by Dr Lee Cohen, said the prevalence of depression in reproductive age women, their level of anti-depressant use and the frequency of unplanned pregnancy, it was important to be able to tell patients about comparative risk of relapse linked to stopping or continuing with their medication.

BBC: NEWS | Health | Pregnancy 'no depression guard'

Around 10 to 25% of women of reproductive age are estimated to be affected by endometriosis and about two million women in the UK have the condition.

BBC: NEWS | Health | A life plagued by painful periods

Nearly 4% of women of reproductive age are infected, as are more than one in 10 police officers and soldiers.

CNN: On the Road Back

The president said 34 million people have AIDS -- and in the developing world, almost half of those with AIDS are women of reproductive age.

CNN: Clinton calls for international family planning funding without restrictions

One, in 1996, estimated that 5% of rapes of victims of reproductive age led to pregnancy, based on repeated phone surveys of the same group of women.

WSJ: Pregnancies From Rape Prove Tough to Count