Double Trouble for Mothers of Twins : Mental health: They are more likely to suffer from depression than women whose babies are born more than two years apart, researchers say.

Mothers of twins are significantly more likely to suffer from depression than mothers of children born more than two years apart, according to research reported in the British Medical Journal.

Karen Thorpe, a psychologist at University of Bristol’s Institute of Child Health, used data from a survey of 12,712 mothers, of whom 139 had twins. The survey, conducted in 1975, had not previously been analyzed comparing mothers of twins to other mothers.

“The emotional well-being of mothers of twins was poor relative to that of mothers of singletons,” she said.

“Fatigue is one factor,” Thorpe said. But there’s more to it: Mental stability is shaken as early as pregnancy, she added.

A twin pregnancy can be more physically and emotionally stressful, Thorpe said in a telephone interview. “Discomfort is exacerbated, with greater feelings of heaviness occurring at an early stage in pregnancy.”

Also, twin pregnancies pose a greater medical risk for both the mother and babies. For instance, she said, these women are prone to hypertension during pregnancy, and the fetuses are at increased risk of growth problems in the uterus. Many of these babies are born too early and require special care after birth.

The anxiety surrounding a high-risk pregnancy can be traumatic, she said, and the financial strain of caring for twins is usually much greater than the parents realized.

The women completed the questionnaire five years after giving birth. Thorpe said the study showed that about a third of mothers of twins showed a tendency toward depression while nearly a quarter of mothers of single babies had scores predictive of depression.

Mothers who had children less than two years apart had scores similar to mothers of twins, said Thorpe, whose study was published in May.

Dr. Elizabeth Bryan, a pediatrician and medical director of Britain’s Multiple Births Foundation, said rearing twins is significantly more stressful than rearing children close in age.

She applauded the study for bringing to light the emotional burden on women that too often goes unrecognized by family members and physicians.

Twins may not cause depression, but “for people prone to depression, having twins may be the triggering factor,” Bryan said.

Her advice to parents of twins is to meet other parents of twins to share feelings of tension and fatigue.

“For the sake of the children, help is essential,” she added.

Twins occur in about one in 90 pregnancies, Bryan said. The increased use of fertility drugs has increased the rate of multiple births. She said the incidence of triplets, roughly one in 3,000 births, has tripled in the last decade.

Thorpe said her study shows the need for programs to help mothers of twins cope.