Breastfeeding duration related to practised contraception in the Netherlands.
OBJECTIVE
The aim of this study was to gain insight into contraception practised and related to breastfeeding duration.


METHODS
Mothers with infants up to 6 months received a questionnaire on infant feeding (breast or formula feeding) and contraception (hormonal or non-hormonal methods). Estimates of the time interval between resuming contraception and cessation of lactation was calculated by Chained Equations Multiple Imputation.


RESULTS
Of all women (n = 2710), 30% choose condoms, 22% the combined oral contraceptive pill (OCP) and few other methods. Breastfeeding was started by 80%, and 18% continued up to 6 months. Of the breastfeeding mothers, 5% used hormonal contraception; 7% of women who used hormonal contraception practised breastfeeding. After adjustment for background variables, the use of OCP is strongly associated with formula feeding: after delivery to the third month postpartum, the crude OR being 17.5 (95% CI: 11.3-27.0), the adjusted OR 14.5 (9.3-22.5); between the third and sixth month postpartum, respectively, 13.1 (95% CI: 8.6-19.9) and 11.7 (7.6-17.9). Of all breastfeeding women, 20-27% resumed OCP at 25 weeks postpartum and 80% introduced formula feeding. The time lag between these events is 6 weeks. Hormonal contraception was resumed after formula introduction.


CONCLUSIONS
Mothers avoid hormonal contraception during lactation; they change to formula feeding 6 weeks before they resume the OCP. To effectively promote longer duration of breastfeeding, the BFHI needs to address contraception as practised.
van Wouwe
Jacobus P
JP
Netherlands Organization for Applied Scientific Research TNO Quality of Life, Leiden, The Netherlands. ko.vanwouwe@tno.nl
Lanting
Caren I
CI
van Dommelen
Paula
P
Treffers
Pieter E
PE
van Buuren
Stef
S
D000293:Adolescent; D000328:Adult; D001942:Breast Feeding / Q000706:statistics & numerical data*; D016001:Confidence Intervals; D003268:Contraception Behavior / Q000706:statistics & numerical data*; D003270:Contraceptive Agents / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007774:Lactation; D008425:Maternal Behavior; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D011795:Surveys and Questionnaires; D013997:Time Factors; D055815:Young Adult
D003270:Contraceptive Agents