Childbirth close to natural menopause: does age at menopause matter?

RESEARCH QUESTION: Does a successful spontaneous pregnancy in the years close to natural menopause depend on age at menopause? DESIGN: This was a retrospective population-based study of 4157 parous postmenopausal women in Norway, born during the years 1925-1940. Data were obtained by two self-administered questionnaires in the HUNT2 Survey (1995-1997). We calculated the proportions of women who gave birth within 5 years and within 10 years prior to menopause both among all women, and according to categories of age at menopause. RESULTS: Overall, 2.7% (114/4157) of all women gave birth within 5 years, and 11.7% (487/4157) gave birth within 10 years, prior to menopause. Among women with menopause before the age of 45 years, 23.5% (81/344) gave birth within 5 years, and 55.5% (191/344) gave birth within 10 years, before menopause. Among the women with menopause at the age of 55 years or older, no women (0/474) gave birth within 5 years, and 0.2% (1/474) gave birth within 10 years, prior to menopause. CONCLUSIONS: More than half of the women with menopause before the age of 45 years gave birth within the 10 years before natural menopause, whereas virtually no women with menopause at the age of 55 years or older did. Thus, the length of the sterile interval before natural menopause may vary by age at menopause.