Risk Factors for Uterine Fibroids among Women Undergoing Tubal Sterilization

Abstract

Uterine leiomyomas are reported to be the most common benign gynecologic tumors affecting premenopausal women, and they are often associated with considerable morbidity. The purpose of this study was to identify risk factors for uterine fibroids among women undergoing tubal sterilization. Cases comprised women aged 17-44 years whose uterine fibroids were first visualized at the time of tubal sterilization (1978-1979 or 1985-1987) or who reported a history of uterine fibroids (n = 317). Controls were randomly selected from women with no laparoscopic evidence of or history of fibroids (n = 1,268). Adjusted odds ratios were estimated using unconditional logistic regression separately for White (n = 1,235) and African-American (n = 350) women. Risk factors for White women included: age 40-44 years (odds ratio (OR) = 6.3; 95% confidence interval (CI): 3.5, 11.6), > or =5 years since last delivery (OR = 1.9; 95% CI: 1.1, 3.1), lifetime cigarette smoking of > or =1 pack/day (OR = 1.6; 95% CI: 1.1, 2.3), menstrual cycle length of >30 days (OR = 1.6; 95% CI: 1.1, 3.3), and menstrual bleeding for > or =6 days (OR = 1.4; 95% CI: 1.0, 2.0). Parous women were at reduced risk compared with nulliparous women (OR = 0.2; 95% CI: 0.1, 0.3). Advancing age was the only significant risk factor for African-American women (ages 40-44 years, OR = 27.5; 95% CI: 5.6, 83.6). Current oral contraceptive use and elective abortion were not associated with fibroids.

Epidemiology of Uterine Fibroids

“…The relationship between UL and menstrual cycle patterns is less clear. In the NHS II, irregular menstrual cycles and longer menstrual cycle length were associated with decreased UL risk [80], but no such associations were found in previous studies [79, 87, 88]. …”

“…Having a child has been associated with a decreased risk of developing UL in many studies [75, 77, 78, 80, 85, 88, 89]. The reduction in risk ranges from 20–50% when comparing parous with nulliparous women, and risk appears to decrease with a higher number of children in most [30, 75, 77, 80, 85, 89] but not all [78] studies.…”

“…The reduction in risk ranges from 20–50% when comparing parous with nulliparous women, and risk appears to decrease with a higher number of children in most [30, 75, 77, 80, 85, 89] but not all [78] studies. Spontaneous abortions or incomplete pregnancies appear to be unrelated to risk [28, 78, 88, 89]. Women with infertility are more likely to have UL [29, 77, 89], particularly women with infertility at younger ages (<25 years) [78, 79].…”

“…Studies more consistently show that the longer the time since the last birth, the higher the risk of UL [29, 30, 75, 77, 78, 80, 88], although the association is not linear in all studies [78]. In the UFS, age at birth in the mid-reproductive years (25–29 years) was most protective against UL [90].…”

Vitamin D and uterine leiomyoma among a sample of US women: Findings from NHANES, 2001–2006

“…Black women are more likely to develop UL, develop tumors at a younger age, develop a greater number of tumors, have more severe symptoms, and are more likely to undergo hysterectomy as a treatment when compared to white women [4–8]. UL prevalence is also associated with age [9], body mass index (BMI) [10, 11], and parity [12, 13]. However, the known risk factors do not fully explain the elevated risk in black women [14].…”