Parity as predictor of early hypertension during menopausal transition.

Objectives: Studies regarding the effects of parity on blood pressure in later life produced conflicting results. The aim of our study is to analyse whether parity influences the prevalence of hypertension in perimenopausal and postmenopausal women.

Methods: One thousand perimenopausal and postmenopausal women (mean age 55.2 ± 5.4 years) were enrolled with a median follow-up of 63.0 months. The study sample consisted of patients who self-referred, in 1998-2009, to the BenEssere Donna Clinic, dedicated to menopause-related disorders.

Results: One hundred and twenty-two (12.2%) women were nulliparous and 878 (87.8%) had at least one child. Thirty-four (27.9%) women among nulliparous and 326 (37.1%) among parous were hypertensive at baseline (P = 0.046) and 812 women (81.2%) were in their postmenopausal period. Univariate analysis showed that women with one or more children were at higher risk of being hypertensive [odds ratio (OR): 1.529; 95% confidence interval (CI): 1.006-2.324; P = 0.047]. Likewise, multivariate analysis revealed that parity (OR: 2.907; 95% CI: 1.290-6.547; P = 0.010), BMI (OR: 1.097; 95% CI: 1.048-1.149; P < 0.001) and family history of hypertension (OR: 3.623; 95% CI: 2.231-5.883; P < 0.001) were independently related to hypertension at baseline. In a subanalysis of 640 initially normotensive women, 109 (17.0%) patients developed hypertension after follow-up, without a statistically significant association with parity (13.6% in nulliparous versus 17.6% in parous; P = 0.362). Consistently, parity showed no relationship with the incidence of hypertension during follow-up (OR: 1.350; 95% CI: 0.707-2.579; P = 0.363).

Conclusion: For the first time in a population of White perimenopausal and postmenopausal women, parity was demonstrated to be independently associated with early hypertension during menopausal transition. Conversely, postmenopausal hypertension was not related with parity.