Natural interpregnancy intervals of fertile couples: a longitudinal survey of grand grand multiparous women.
OBJECTIVE
To characterize the natural fecundity of grand grand multiparous women (> or = 10 deliveries) in relation to age, number of pregnancies, body mass index, and chronic diseases.


METHODS
A retrospective longitudinal analysis of interpregnancy intervals of married couples who had never used any kind of contraception.


METHODS
The interpregnancy intervals (months from delivery or spontaneous abortion to the next conception) of 96 grand grand multiparous women with a total of 1,327 pregnancies were evaluated from the first to the latest pregnancy (14 +/- 1.7; mean +/- SD). Because of the lack of reliable data on conception times, 109 pregnancies had to be excluded. The number of interpregnancy intervals remaining for evaluation was thus 1,218.


RESULTS
The mean interpregnancy intervals in the material of 1,218 pregnancies was 8.5 +/- 4.9 months, being significantly shorter after an abortion (5.3 +/- 4.8 months) or stillbirth (6.0 +/- 4.7 months) than after a delivery (8.9 +/- 5.6 months). The interpregnancy interval was significantly longer in women over 30 years of age than in the younger women, approximately 7 months in the latter and exceeding 10 months around the age of 40 years. Body mass index and chronic medical illness did not influence the interpregnancy intervals. The incidence of spontaneous abortions increased after the age of 30 years. It was 6% until 30 years, 10% between 31 and 35 years, and 25% after 40 years.


CONCLUSIONS
In this retrospective longitudinal review, the reproductive capacity of fertile couples remains rather sound until premenopausal age. The data suggest that a woman's delivery capacity could be 25 births between 16 and 45 years of age.
Juntunen
K
K
Department of Obstetrics and Gynecology, University of Oulu, Finland.
Kirkinen
P
P
Kauppila
A
A
D000028:Abortion, Induced; D000022:Abortion, Spontaneous; D000328:Adult; D001721:Birth Intervals; D015992:Body Mass Index; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D007246:Infertility / Q000503:physiopathology*; D008137:Longitudinal Studies; D008875:Middle Aged; D010298:Parity; D011247:Pregnancy; D011261:Pregnancy Trimester, First