According to the World Health Organization, 10 percent of pregnant mothers and 13 percent of women who have just given birth experience a mental disorder, most often depression. In some cases, the suffering is so acute they commit suicide. A new drug -- the first to specifically treat post-partum depression -- has just hit the market in the US. Karina Huber has more from New York.

Six months into Sara Rempe's pregnancy with her son Ezekial she had a severe four-day panic attack - that felt both physical and mental.

SARA REMPE TEACHER AND MOTHER "I would feel heat and tingling come up over my back in waves and I would sweat and my stomach would knot and I would just be in dread and fear."

Rempe had experienced anxiety before but this time the stakes were much higher.

SARA REMPE TEACHER AND MOTHER "Any scary thought is ten times scarier because you have your baby that you want to do the best for."

It was out of concern for her baby that Rempe went off anti-depressants during her pregnancy. It was not the right move. People with a past history of anxiety and depression are more vulnerable to developing it during and after pregnancy and the consequences for both mother and child can be severe. While Rempe had extra reason to be concerned, hormonal changes during pregnancy cause many women to experience mental disorders for the first time.

KARINA HUBER NEW YORK "A new treatment, the first that specifically targets post-partum depression was recently approved by U.S. regulators. Called brexanolone, marketed under the name Zulresso, it acts within 48 hours - much faster than traditional anti-depressants."

But it must be administered in a clinical setting because the drug is given intravenously over a period of 60 hours.

DR. CATHERINE BIRNDORF CO-FOUNDER, THE MOTHERHOOD CENTER "Right now. If you want to go through with that, you really need it."

Doctor Catherine Birndorf is a reproductive psychiatrist. She says an intravenous treatment will likely only appeal to people suffering from severe depression who need treatment quickly. Another challenge for patients is cost - 34,000 dollars per treatment not including the three-day stay in a medical facility.

DR. CATHERINE BIRNDORF CO-FOUNDER, THE MOTHERHOOD CENTER "It's just out there and I don't know what the negotiations are yet with insurance companies to hopefully pay most if not all of that because if that doesn't happen, forget about it. No one's going to be using this drug."

Rempe agrees it needs to be made more affordable but she is happy to see a quick-acting option on the market.

SARA REMPE TEACHER AND MOTHER "If it were available to me and they said if you do this thing you'll be better, I would do it."

Karina Huber, CGTN, New York.