Menstruating early — before age 12 — is linked to an increased risk of heart disease and stroke later in life, a new study suggests. It is one of several reproductive risk factors, including early menopause, complications of pregnancy and hysterectomy, which appear to be associated with subsequent cardiovascular disease, the results show.
The research team drew on data from more than half a million men and women up to age 69 and recruited between 2006 and 2010, none of whom had cardiovascular disease when they entered the study — traced back to March 2016 or until they had their first had a heart attack or stroke, whichever came first. The average age of the women at the start of the study was 56 and about half (51%) were from the wealthiest segment of the UK population. Six out of ten had never smoked.
The mean age at which they started menstruating was 13; most (85%) had been pregnant and almost half (44%) had two children. On average, they were 26 when they had their first child. One in four women had a miscarriage and 3 percent had a stillbirth. Nearly two-thirds of them had gone through menopause, averaging 50 years of age. About four out of 10 men (42%) had fathered two children before the start of the study.
During a monitoring period of approximately 7 years, 9054 cases of cardiovascular disease were recorded, of which a third (34%) were in women. This included 5782 cases of coronary artery disease (28% women) and 3,489 cases of stroke (43% women). Analysis of the data showed that after taking into account potentially influential factors, women who started menstruating before age 12 had a 10 percent greater risk of cardiovascular disease than those who were 13 or older when they started. . Similarly, those who went through menopause early (before age 47) had a 33% increased risk of cardiovascular disease, rising to 42% for their risk of stroke, taking into account other potentially influential factors. Previous miscarriages were associated with a higher risk of heart disease, with each miscarriage increasing the risk by 6 percent. And stillbirth was associated with a higher risk of cardiovascular disease in general (22%) and stroke in particular (44%). Hysterectomy was linked to an increased risk of cardiovascular disease (12%) and heart disease (20%). And those who had their ovaries removed for a hysterectomy were twice as likely to develop cardiovascular disease as those who didn't have these procedures. Young age at first parenthood seemed to be another risk factor, with each additional year reducing the risk of cardiovascular disease by about 3 percent.
But the association between the number of children and cardiovascular disease was similar for men and women, suggesting that social, psychological and behavioral factors may be more important than biological ones.
